Powerplants => LT# & LS# => Topic started by: skisix38off on November 28, 2018, 08:08:48 AM

Title: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on November 28, 2018, 08:08:48 AM
I've started my journey into the LS swap area.  My Poncho 400 is made of good parts and has done a great job of taking me this far, now it's time to get some good power to the ground and to make the car more reliable.  I bought a GM Performance Crate LS376/515 - this is an LS3 with the LSA Racing cam in it bringing it to a rated power of 533hp and 486tq.  It has 871 heads and the Victor Jr intake manifold as opposed to the typical MFI black plastic intake.  I want this to work with my shaker and while I could develop a way to mount my shaker with the plastic intake, I just want to keep my shaker functional without fab'ing something up.  I will also be using a Holley Terminator LS system to control the ignition and provide Fuel Injection.  I am looking forward to all the benefits of FI on this car and to have the computer make the adjustments to keeping it running well and me not having to guess at which secondary rods to use and all the other stuff associated with maintaining a premium tune. 

I have bought a new LS conversion radiator to keep it cool and will use 4th gen dual electric fans controlled by the Terminator system.  I went to BRPHotrods.com to get the engine mounts and trans crossmember for the T56.  The T56 is going to be rebuilt to handle the new power/torque.  And I also purchased a AutoWire harness to go to the terminator system and to feed the Dakota Digital gages.  I bought a new fuel tank with in tank pump to supply fuel. 

At this time I will use the supplied exhaust manifolds and fab a mid-pipe to go from there to the current exhaust.  As part of this change over I will also go to a 4 link in the rear to handle the new power- those leaf springs don't stand a chance!

The new crate engine arrives!
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272622256/small/1543412729/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272621927/small/1543412716/enhance)

I think that Victor Jr intake looks great!
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272621514/small/1543412702/enhance)

Out of the crate and onto a stand.  I have to do this step because the LS376 comes with an oil that doesn't work for 2nd gen F-bodies, and I am installing an Improved racing oil pan baffle to help ensure that the engine is always supplied with oil.
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272562242/small/1543410772/enhance)

Now for the Current set up...
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272621114/medium/1543412686/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272620637/medium/1543412669/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272620117/small/1543412654/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272619564/medium/1543412636/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272619085/medium/1543412621/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272570642/medium/1543411083/enhance)

Soon, the transformation will take place.  I am hoping to have it driving again in early Feb., 2019.

Pit crew and security crew! 
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272561423/medium/1543410744/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124272558788/medium/1543410632/enhance)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Steve B on November 28, 2018, 08:16:29 AM
Good luck with the swap.  I think the dogs might need to be put to work to help out. :lol:
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on November 30, 2018, 01:41:34 PM
Looking great! you won't be disappointed with the LS motors. My dad just picked up a Terminator kit recently and we're looking forward to installing it on his 1971 Chevelle with a 496 BBC. Keep us posted!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 03, 2018, 07:57:37 AM
I had to do a few little custom touches this weekend. 

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124293742139/medium/1543844964/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124293742472/medium/1543844976/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124293741375/medium/1543844941/enhance)

I also received and installed my Improved racing Oil Pan Baffle to help keep the oil pick up covered in oil even on high G corners.  This is a nice piece. I also got my 4TH Gen Oil pan to install it in. 

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124293757460/medium/1543845337/enhance)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: 1979 Black and Tan on December 03, 2018, 01:06:02 PM
very nice..is there a reason you went with a carburetor and not with the fuel injection that usually comes with these GM engine packages?

like this one

https://www.chevrolet.com/performance/crate-engines/dr525-muscle-car-oil-pan
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 04, 2018, 07:39:07 AM
More goodies arrived!
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296828151/medium/1543889218/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296831646/medium/1543889240/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296832010/medium/1543889243/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296832579/medium/1543889247/enhance)



Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 04, 2018, 07:49:23 AM
very nice..is there a reason you went with a carburetor and not with the fuel injection that usually comes with these GM engine packages?

like this one

https://www.chevrolet.com/performance/crate-engines/dr525-muscle-car-oil-pan

I was originally going to buy the engine you linked above.  There are several factors involved in my case, cost and availability, and it's very important to continue using my shaker.  The more I get into this though, I am so glad that I made the decision I did.  See below...

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296826638/medium/1543889203/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296826916/medium/1543889206/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296827136/medium/1543889208/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296827433/medium/1543889211/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124296827842/medium/1543889216/enhance)

I do have fuel injection!  I will have all the conveniences of FI and all the performance advantages of FI.  And this system allows a DIY'er like me install anLS engine just like it was any Pontiac engine and this route is $2000 cheaper.  The Terminator LS system will also allow me to go to Multi-Port in the future if that's what I want.  Most of all, I believe the air cleaner, thus shaker, will fit right on top!  Then, there's the cool factor when the hood is up.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on December 04, 2018, 09:39:26 AM
Great choice! I will be helping my dad install his Terminator EFI this winter too. Hopefully tearing up the streets this spring! Keep us posted on your progress.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: jonathonar89 on December 04, 2018, 11:05:47 AM
Exactly how I think shaker T/A guys should be doing their LS swap right here.  950cfm 4 Barrel

Good stuff.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: 1979 Black and Tan on December 04, 2018, 03:28:22 PM
this looks amazing....
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 05, 2018, 07:39:17 AM
Steam vents????  Can someone chime in on this?  This is a detail about LS that I have read as being very important, how does it get connected?  Part Numbers?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on December 05, 2018, 08:36:53 AM
Mine is T-ed into the upper radiator hose similar to how it was done on some LS based GM trucks.  I haven't had any issue using this, but have not had an opportunity to do any type of competition such as your car sees.  I am using a transition from jagsthatrun.com.  https://jagsthatrun.com/collections/cooling-systems

I have a 17 SS and the line is attached at the top of the radiator just above the inlet for the upper radiator hose. 

If you decide to run an expansion tank, it may have a dedicated provision for this line.  C & R Racing tanks do.  Some find factory tanks at the junk yard and use them. 


The earlier LS motors had 4 ports all tied in together from both the rear and front.  I believe it was to prevent a particular piston or pistons from overheating.  At some point, only the front ports were open and required venting. 
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 05, 2018, 10:52:35 AM
Do I have this correct?

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124302894554/medium/1544028508/enhance)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: jonathonar89 on December 05, 2018, 11:09:36 AM
Do I have this correct?

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124302894554/medium/1544028508/enhance)

Yes
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on December 05, 2018, 11:59:19 AM
At the rear of your picture, the part that is just off center of the intake is the oil pressure sender.  The port on the drivers side valve cover is capped off on my 11 production engine (Corvette based) and on my 17 SS.   Some use these ports for catch cans/oil separator. 

The front PCV port can be tied in after the MAF to keep it cleaner from oil.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on December 07, 2018, 07:17:28 AM
Yes, Updated71 is right the port on the rear of the valley cover is for oil pressure.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 18, 2018, 08:53:21 AM
Not much progress in the last week...

I did a little bit of visual progress work.  I wanted verify that the air cleaner assy would actually go on the Holley and it does so, now, I just have to determine where the engine will sit in the engine bay and if the shaker will poke out in the same spot as the hole in the hood.

I also got the harness out from the Holley to start figuring out where things go.  The harness is very well done.  To me, without reading any instructions, I'm wondering how I will get the Crack sensor to connect and a few other sensors as well.

Another question for you TA guru's that have done several projects like this.  I bought an American Autowire update kit, the one to make the car work with an LS.  Does anyone have any tips for installing this kit specifically, or installing a new wire harness in general?  I'm thinking that getting the engine out and having some room to work will be a good thing.  How about the dash?  Remove the dash and then just take everything out?

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124355453367/medium/1545142500/enhance)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on December 18, 2018, 10:34:19 AM
AAW makes a great harness.  You will need their crimpers.  They provide fused power for a fuel pump, keyed ignition (2), constant 12v.  I didn't use a Holley harness, but on the harness for engine management I did use (Speartech on one install), I was able to by-pass the Speartech fuses and wire directly to the power wires AAW provided.  It gave a much cleaner look similar to what the factory would have done.  I also bought some extra connectors and terminals that I used to wire other things so that every wire was a plug in connector. 

Rewiring the car will take quite some time to make sure everything is neat and laid out correctly.  It's actually one of my favorite parts of working on a car.  I also added mesh loom and heat shrink tubing on some of the parts of the harness for a cleaner look. 

Other than their crimpers, which are avilable for rent through them, I use a Power Probe (great tool to have), good wire strippers and a terminal removal kit.  The terminal removal kit comes in handy if you decide to add the mesh loom and shrink tube the ends for a finished look.  It also will help you remove some of the terminal bodies from your old harness.  They clean up easily and you won't have buy them.  You would just need more terminals. 

They send practice terminals and you should practice on them if you've never worked with Packard 56 terminals before.  Some may need a run over a file at the locking tab for a good fit.  There are videos on line that show this.

One place I added connectors was at my aftermarket gauges.  Another was at my electric trunk release. 


Excited to see how the shaker fits.  I used a Holley system many years ago when they still used dip switches for adjustments.  It still did good for how little adjustability was built in. 

Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on December 18, 2018, 10:53:44 AM
To answer the question you had about the crank position sensor, I think it would depend on what kit you bought. My dad just bought a Terminator kit recently and it was meant for traditional SBC/BBC distributors and the computer just needs a signal from the tach to know what the engine speed is. If you bought the kit with the injectors and such in the TB, I think you may need another harness that integrates for the LS motor, then use the TB for things like the TPS, IAC, MAP and etc.

Also, regarding the Packard 56 Terminals after a ton of research for a cheaper alternative to the AAW or Waytek crimpers I found that a cheap ratcheting crimper on ebay for $15 bucks that does a good job with the Packard 56 Terminals. I can get a part number when I get a chance if you are interested. They do need to be modified slightly as the jaws are slightly too wide and distort the terminals.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 18, 2018, 11:31:35 AM
Thanks for your comments.  I will need to look into those crimpers and get some practice in on them.

ryeguy - If you can get that number on those Ebay crimpers that would be great!  Also, I got the Termintor LS system, I hope that I don't need another harness to make it work.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on December 21, 2018, 01:31:31 PM
Here is the link to the ones that I bought. In my build I think I took some pictures of the crimps that it did. I need to get my angle grinder and shave a slight bit off the end so that it doesn't distort, but otherwise great. I will tell you it's a heavy crimp, definitely need two hands, but I'm thinking of adding a longer handle to get more leverage.

https://www.ebay.com/itm/Crimper-Crimp-Pliers-Set-0-5-35-mm2-Crimping-Tool-Kit-Ratchet-4-Spare-Dies-W-Bag-/172669726736?hash=item2833eaf010
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 24, 2018, 07:01:36 AM
More carnage going on in the Busted Knuckles garage!  I just wish that re-assembly was as easy as the disassembly!  I go the engine out, dash out, interior out and the dash harness out in 1.5 days.   I hope I can get it back in and all together in the next 6 weeks.

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124368507621/medium/1545655750/enhance)

My son home from college helping out..
(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124368507604/medium/1545655748/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124368507584/medium/1545655745/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124368507548/medium/1545655742/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124368507496/medium/1545655736/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124368507480/medium/1545655734/enhance)

Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on December 24, 2018, 09:18:02 AM
What trans are you going with?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: scarebird on December 24, 2018, 09:36:10 AM
Powerglide!





*runs away*


/you know somebody's done it...
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 25, 2018, 07:33:26 AM
What trans are you going with?

I've been running a T56 for the last year, and I love it!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on December 27, 2018, 12:40:33 PM
What trans are you going with?

I've been running a T56 for the last year, and I love it!

So you'll need to run the reverse light wiring, reverse lock out and speedo wiring depending on your gauge set as far as that area is concerned. How have you been running the reverse lock out until now?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 29, 2018, 06:54:39 AM
I haven't had the reverse lock out wired in.  I have only been running the reverse lights, no lock out, no neutral safety... 

I have been making some slow progress, a lot of little things getting done.  I've had the engine in and out several times already just to find out how and where it would sit.  The T56 is out getting a Texas Drivetrain Performance upgrade to stage 3 so it can survive the new LS.  I'm very excited to say that this LS sits about 4" further back in addition to being a couple hundred pounds lighter the new placement will also increase it's balance front to back.

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124380876018/medium/1546086841/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124380876004/medium/1546086838/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124380875987/medium/1546086835/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124380875946/medium/1546086828/enhance)



Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 29, 2018, 06:58:09 AM
One of the things that will be coming out of the engine bay in this swap is the heater box.  What have folks done to get the blower to vent inside after removing the box?  I know there are companies like DSE that make the block off plate but, how does the blower get inside the cabin?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: scarebird on December 29, 2018, 12:10:27 PM
I don't think you can - the fan sucks air from the windshield base, the output is ducted thru the engine compartment by the firewall duct.  You can use the side vent but of course need to be moving.

Some GM had power vents in the side plenums, maybe that is what you will need to mimic...
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on December 30, 2018, 02:14:07 PM
Help!  I fallen in Wiring hell and can't get up!!!!

There is a lot of wiring and initially it's intimidating but, after sitting with it and putting my hands on it several times and starting to map out where things are going and how they are routed it seems better.  Just waiting for a crimper now, should be here in a few days.

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124384065459/medium/1546199492/enhance)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on December 30, 2018, 03:46:01 PM
I think that was my favorite part of the LS swap.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on December 31, 2018, 10:30:21 AM
I penciled in changes on the AAW instructions.  I also checked off each circuit as it was completed.  My car has no power windows or locks.  I used those for power for other things I needed.  There are a few wires that are just pass though wires at the bulkhead.  Off the top of my head, the tach and alternator exciter wires (white and brown IIRC) are 2 such wires.  If you don't need either, you can use those for anything else that needs to go from inside to outside of the car.  I'd have to look at my notes, but I believe I used those for fan trigger wires (dual fans).  My tach is fed from the PCM to a Speedhut gauge.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 02, 2019, 07:16:19 AM
The engine is in, it may change slightly when the T56 gets bolted up next.  I decided to do some "motivation work" and skipped ahead a bunch of steps...

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124390355005/medium/1546392525/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124390355289/medium/1546392529/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124390355872/medium/1546392539/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124390356110/medium/1546392542/enhance)

Question for you folks that have done this before...  What did you do with the water pump heater ports?  See below.

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124390354578/medium/1546392518/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124390354450/medium/1546392516/enhance)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on January 02, 2019, 07:31:15 AM
I have seen others pull the pressed in sleeves and tap the hole for pipe thread and then use 90° fittings. My engine didn't sit back so far and just cleared so I lucked out.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on January 02, 2019, 09:25:24 AM
These L shaped hoses worked for me:


(https://i.postimg.cc/PqvWkhz0/IMG-1661.jpg) (https://postimg.cc/06xMpT4C)

I added a bracket to the control arm stud and added a 2nd nut to hold it in place.  I don't have a pic of how it ended up, but here's one just to give you an idea.  I added adele clamps to hold the hoses in place loosely to allow for expansion.  I also rounded the edges of the guard.  If I find a pic, I'll post it:

(https://i.postimg.cc/5tyPYZ5m/IMG-2282.jpg) (https://postimg.cc/d7MRgNx7)

Not sure if you have more clearance than I did when I ran this set up:

(https://i.postimg.cc/nL36N423/IMG-1595.jpg) (https://postimg.cc/DWbjXbtG)


Title: Re: LS376/515 swap in a '78 Trans Am
Post by: scarebird on January 02, 2019, 12:50:30 PM
45° fittings, pipe tap - male one end, female other, then 5/8" and 3/4"Ø nipples screwed in.

(http://forums.maxperformanceinc.com/forums/attachment.php?attachmentid=417165&d=1451712356)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 02, 2019, 01:58:13 PM
Thanks Guys!  I appreciate the response.  For what I do with my car, I want as much engine behind the front axle line as possible for weight balance.  For installation, I would have fewer issues to deal with if I picked the forward two mounts on the Muscle rod motor mounts.  Hmmmmm.....
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on January 03, 2019, 10:23:48 AM
I figured you set it back for weight reasons.  I didn't even have to notch the frame for the alternator.  I used the dirty dingo motor mounts. AC is going to be a late 90s pump top mounted when I get to that point.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on January 17, 2019, 10:22:10 AM
Any updates?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 18, 2019, 03:18:27 PM
It's been a while since any updates...  Partially due to having other things to get done and partially due to determining the best direction to go forward.  The holes in the K member located the tailshaft of the transmission about 2" off center line and had to be re-done, and since I was there already I just welded in nuts so that I don't have to dink around with the piss poor GM design of having a back up nut!  That's solved I played with the two positions the motor mounts can go in and, at least on my subframe, there were more changes to make in the forward position than the back position so back it is!  The cut out in the tunnel is nearly filled but the Direct Fit Muscle Rodz crossmember is not done as well as it can be.  They made it very strong but there is a flange in the front of the slot to bolt the trans to that would require lifting the trans 4" higher than it's working position and the clearance to the tunnel would be ridiculous.  So, I modified the crossmember and things are going smoothly again. 

I also got the front light harness terminated and in place.  With the way American Autowire does there kits, it's lost on me why they couldn't terminate the front lights and have everything in place so that it really was pull the old one out and install the new one.  The crimpers work great reyguy- thanks for that tip!

Promising Pictures next week.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 22, 2019, 08:09:58 AM
Pictures!  Although, I don't think they capture the amount of work done...

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124430038996/medium/1548165879/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124430039471/medium/1548165908/enhance)

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Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Nexus on January 22, 2019, 10:55:11 AM
Progress is the difference between visual progress where it looks like lots gets done with little work and actual progress where the hours put in go unseen as all you did was put in new wiring...how hard can it be?

lol...get work and keep ticking away at it...I look forward to more updates!!!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 22, 2019, 02:38:41 PM
I have been studying the wiring a lot ...  The Holley system has provisions to get engine temp and oil pressure so it can do it's job, what I haven't been able to find is how to get oil pressure and engine temp to the Dakota Digital VHX new gages.  I called both Holley and DD today to ask how they have done this in the past and was disappointed to hear each of them respectively pointing fingers at the other.  Both suggested that I use two sensors for each- one each for Holley and DD.  Surely that can not be a very good solution?  DD has an interface box, another $100, that is specific to the Holley EFI systems but, "they can't guarantee  that Oil pressue will go accross".

So, where are there other ports for engine temp and Oil pressure?  Isn't there Oil Pressure by the oil filter- I maybe just drill and tap for 1/4" NPT?  Also, any suggestions on pressure sending units for LS?  The Holley unit they told me to get is another $135!!!!  Who buys a $135 oil pressure sending unit?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on January 22, 2019, 02:56:14 PM
I drilled the boss by the oil filter. I don't know what the LS3 has, you may need to get an ls1 version. I'll see if I can find a picture. I drilled the top of my water pump for my temp sending unit.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on January 23, 2019, 09:58:16 AM
I initially did the boss by the filter too, but didn't like how close it put the large sender so close to the header tubing.  It definitely got quite hot.  I eventually moved it to the factory location on the valley cover using a T fitting I found on line.  One end is for the gauges and the other is for the PCM harness. 

This is the on line pic I used for reference.  I can take a pic of it on my car and get the fitting info if this is a direction you'd want to go. 

(https://i.postimg.cc/9fNBHvZb/oil-pressure-swivel.jpg) (https://postimages.org/)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 23, 2019, 03:32:56 PM
I initially did the boss by the filter too, but didn't like how close it put the large sender so close to the header tubing.  It definitely got quite hot.  I eventually moved it to the factory location on the valley cover using a T fitting I found on line.  One end is for the gauges and the other is for the PCM harness. 

This is the on line pic I used for reference.  I can take a pic of it on my car and get the fitting info if this is a direction you'd want to go. 

(https://i.postimg.cc/9fNBHvZb/oil-pressure-swivel.jpg) (https://postimages.org/)

I would appreciate that- I too am not wild about having sensors that low and right next to headers.

Thanks.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on January 23, 2019, 03:50:34 PM
I did buy it from over seas.  It came very quickly though.    Approximately 3 weeks if I remember correctly.  Google the part number and maybe they are now available here.  Either way, I am pleased with the way this went. 


https://www.aeroflowperformance.com/af166-05-02s

(https://i.postimg.cc/50hc94Cr/oil2.jpg) (https://postimg.cc/bD9V3jL0)
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on January 23, 2019, 03:56:30 PM
Also, I believe I needed a slightly longer coupling for the factory sensor up top.  That was about $2 in the plumbing department locally.  The sensor is what is required for my Speedhut gauges.  It is a common early GM sensor.


The other part of your question was engine temp.  My Speartech harness gets temp info from the drivers side front of the head near the first plug wire.  I added the Speedhut sensor for my gauge to the same spot on the passenger side, but at the rear of the head (the heads are the same so looking at it from the passenger side puts that port opposite of the drivers side).  I had to remove a factory pipe plug and use a metric to standard adapter IIRC. 

I couldn't find a way to just use one sensor in either application.  They both use a different input signal to read correctly.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on January 24, 2019, 02:29:37 PM
So, I understand why DD needs the oil pressure sender because that is what you will see on your cluster, but I'm curious why the terminator needs to see oil pressure? I don't believe that my dad's Terminator kit had an oil pressure sender in his kit? He had a fuel pressure sender in the kit. Is there an option with Terminator to kill the fuel pump if it doesn't see oil pressure or something?

On both of my LS swaps, I deleted the factory oil pressure sending units because they don't tie into the ECU. I have thought about wiring in a fuel pump kill switch inline with the fuel pump relay to kill the pump if the oil pressure dropped below like 5 psi.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on January 25, 2019, 07:50:23 AM
A little break from wires..

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124434543187/medium/1548423465/enhance)

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124434543019/medium/1548423443/enhance)


Title: Re: LS376/515 swap in a '78 Trans Am
Post by: jonathonar89 on February 04, 2019, 09:51:12 AM
Do you have any more pics of the Dakota Digital install?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on February 04, 2019, 09:53:30 AM
Do you have any more pics of the Dakota Digital install?

Not yet, soon though.  Are you looking for anything in particular?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on February 04, 2019, 09:57:57 AM
Moving back to the engine bay...  Spent entirely too much time, and time I don't think I had in order to be running for the March 9 Lone Star Good Guy's Autocross, on the inner fenders cleaning out the undercoating and filling holes.  With the new layout, there won't be any wires showing and the inner fenders are going to be clean- so I had to make them presentable....  That turned in to the rest of the engine bay and that consumed the entire weekend.  I have to say I am pleased with the result!

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124451255352/small/1549288663/enhance)

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Title: Re: LS376/515 swap in a '78 Trans Am
Post by: jonathonar89 on February 04, 2019, 10:02:29 AM
Do you have any more pics of the Dakota Digital install?

Not yet, soon though.  Are you looking for anything in particular?

Just curious to see how it mounts behind the dash bezel.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on February 04, 2019, 02:50:16 PM
Were your gauge made from stock images or did you upload your own image. I like them, they look close to stock.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: jonathonar89 on February 04, 2019, 04:26:21 PM
Were your gauge made from stock images or did you upload your own image. I like them, they look close to stock.

That’s the gauge setup from Dakota Digital.  Only comes that way.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on February 05, 2019, 07:09:59 AM
Oh, for some reason I thought he said he was using speedhut sending units so I figured the gauges were speedhut too. They look nice. Thanks!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on February 05, 2019, 07:18:28 AM
Were your gauge made from stock images or did you upload your own image. I like them, they look close to stock.

These are Dakota Digital's VHX gages for a Pontiac.  They are close to the factory looking gages, not a re-done factory gage though.  I got new gages because:
1) I had to do something to get a speed reading.  The T56 only outputs a VSS signal, so I either had to buy a $300 adapter to go to the factory gage or buy a new digital gage to read the VSS signal.
2) With the new engine I wanted a more trustworthy reading of oil and water temp.
3) I wanted to be able to read the gages at dusk, not just full dark.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on February 21, 2019, 08:20:24 AM
I got a lot of work done- I just don't believe a camera will capture it.  I have all the wires connected that I'm going to connect right now- things like courtesy lights and glove box lights and cigarette lighter things I don't need to have done right now so, they are covered up.  The Dakota system is all wired and the Holley is all wired- just waiting for voltage.  I put a hole in the new transmission tunnel to run the wires from the trans to the dash, rather than running them thru the firewall, a cleaner install I believe.

I also ran the braided fuel line but didn't have the fittings I needed, or the regulator and filter to finish that job- I do now and hope to get that finished this weekend.  I also hope to get the exhaust finished so that I can power the system and if....  Big if, everything works and there isn't a bunch of smoke come out - I can start it!!!!!!!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on February 21, 2019, 09:14:45 AM
Good luck!!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on February 25, 2019, 08:11:11 AM
A little more progress over the weekend.  I took Sunday off of race car building to go do some racing..  That was seriously fun and I was happy to catch up with a lot of the local people that I haven't seen in a while.

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124479208442/medium/1551102710/enhance)

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(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124479212161/medium/1551103081/enhance)

Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on February 27, 2019, 08:29:03 AM
I'd say that's some good progress there! What are you doing for a fuel pump, regulator and etc.? Also, where did you get that overflow tank, I want one!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on February 28, 2019, 01:21:33 PM
I'd say that's some good progress there! What are you doing for a fuel pump, regulator and etc.? Also, where did you get that overflow tank, I want one!

Thanks!

The fuel pump is in the tank and what came from Tanks Inc., for this conversion.  It's the 630 hp capable version.  The overflow came from Summit Racing and is a "universal" tank.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on March 05, 2019, 07:46:38 AM
Some more progress!  I have the exhaust tacked into place and it fits up very nicely to the floor - I'll have some ground clearance this year!!!!!
Also got a Hurst shifter for the T56- this shifter has a stud that the actual shift lever bolts to.  I want this because the location of the shift needs to be offset a bit to fit better in the  automatic console that I run. 

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124487259204/medium/1551708107/enhance)

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Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on March 20, 2019, 07:19:41 AM
I have enough together now that I have started to crank the motor with the starter - no gas because I don't want it to start until I see oil pressure.  Once I see oil pressure, I will connect the coil packs and put gas in and test/prime the fuel pump.

So, I watched several videos of how to prime the oil pump in an LS motor because I changed the pick up tube and pan.  I put slight pressure on the oil port on the side of the motor by the timing cover and I put around 2 quarts oil in that way.  After cranking in bursts of 10 seconds, about 6 times I still have no oil pressure and there isn't any sign of oil at the oil pressure port on the valley cover.  I will need to check to see if the oil filter is full, perhaps I didn't fill that. 

(https://uniim1.shutterfly.com/ng/services/mediarender/THISLIFE/007023364607/media/124505576378/medium/1553087065/enhance)

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Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on March 25, 2019, 07:04:36 AM
So much for planning to start the engine this weekend!  After going thru a lot of trouble shooting with Holley Tech Services Sat.,  I boxed up the harness and computer to send back to Holley.  Seems the crank signal was grounded somewhere, could be the harness or the computer.  I got some other misc. things taken care of to stay on track moving forward.

Hopefully I get the parts from Holley Thursday.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on March 25, 2019, 09:28:45 AM
That had to a pain.  I had a harness issue that took quite a bit of time to sort out.  In the end, pulling it and putting in another brand fixed an issue. 
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on March 27, 2019, 08:21:59 AM
What a bummer... My dad and I plan to install his Terminator kit sometime in the month of April. I'm hoping we don't have a similar issue.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on March 28, 2019, 07:26:23 AM
In case this helps anyone else...

I don't fault Holley for this very much...  In my case, I followed the guide exactly, I went through the "wizards" to set a base program and the TPS autoset.  This made it look like everything was reading correctly - MAP, MAT, batt, etc...  When I cranked the motor though, there wasn't any rpm reading so that made it look like the crank sensor wasn't right.  Even after unplugging the crank sensor the rpm read 0.  This is why the Holley tech thought there was a short in the rpm signal - he said it should read "stall" or a value other than 0.

When I was wiring the system, there is a loose red/white wire and it was unclear to me if that should go inside the cabin to a keyed source or a always on source.  I called Holley and the tech told me that needed to be "always on".  So I connected it to the battery.  Well, the Holley computer doesn't save the calibration file unless the power is removed from that wire for 4 seconds.  Since I had it on the battery , when I turned the key off didn't make any difference.

Holley is overnighting the package to me and I will make that change and try again, hopefully with better results.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on April 01, 2019, 06:02:35 AM
Very interesting, sounds like you have figured it out then. My dad and I have been working along on his install and we are hoping to test fire next weekend. I'll be interested to hear how you make out when you get the harness back.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 01, 2019, 07:25:36 AM
Got the Holley stuff back and resolved an issue with the new AAW fuse box!  Now, things power up and shut off when they should,  I like that!
Still no running though- I'm a magnet for trouble.  I believe my fuel pump is bad and isn't putting out enough flow to make the kind of pressures the rest of the system needs.  That took a full weekend of troubleshooting.

I did get it to run very briefly by adding fuel manually- sounded great!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Nexus on April 01, 2019, 01:59:52 PM
Right on...glad it fired up for you...very cool
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 03, 2019, 06:48:08 AM
Fuel Pump!  I worked with Tanks Inc. and they were very helpful!  Their tech went through a bunch of tests they wanted me to do, most of which I already had results for, and then I just told the guy that what I really wanted was for them to send me a new pump.  The guy said ok!!!!!  They got it to me last night and the new engine is ALIVE!!!!  Sounds great too!
I know, worthless without video and I will get that this weekend, that's the next time I have available for it.  Time to get all the rest of the parts back on and make it a car again!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Nexus on April 04, 2019, 10:25:25 PM
Fuel Pump!  I worked with Tanks Inc. and they were very helpful!  Their tech went through a bunch of tests they wanted me to do, most of which I already had results for, and then I just told the guy that what I really wanted was for them to send me a new pump.  The guy said ok!!!!!  They got it to me last night and the new engine is ALIVE!!!!  Sounds great too!
I know, worthless without video and I will get that this weekend, that's the next time I have available for it.  Time to get all the rest of the parts back on and make it a car again!

Its ok...we don't mind waiting for the video...a short while anyway...lol

super pumped its working for ya!!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 05, 2019, 07:34:16 AM
And the loooooooong awaited video!  So, at this point, the engine has run for maybe a total of 1 min in short 30 sec. spurts.  There's a lot of tuning left to do, I just didn't get to it all during this run, maybe another 5 minutes.  Runs by itself now that I can get the rest of the car back together - full interior, trunk, dash, and the brake booster and plumbing all need to go back in.

https://youtu.be/vKPaS3YqzGQ
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on April 05, 2019, 03:50:59 PM
Congrats! We're hoping to start my dad's Chevelle this weekend.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on April 08, 2019, 11:52:31 AM
Anymore progress?? We got my dad's Chevelle going this weekend and honestly has me looking at one for my Camaro. Curious to hear about yours.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 09, 2019, 07:26:04 AM
Anymore progress?? We got my dad's Chevelle going this weekend and honestly has me looking at one for my Camaro. Curious to hear about yours.

Not much time to put into lately.  The progress I've made is that I've gotten the heater control working again and the stereo the dash back on.  Next is to finish the interior.  Then, the brake booster and flush/bleed of the that and the clutch.  At that point I'l start to drive it around some without a hood - I still need to get the shaker to fit to the new position of the TB.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on April 23, 2019, 07:10:09 AM
Tearing up the streets yet?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 24, 2019, 06:42:10 AM
Still dreaming of tearing up the streets!  I don't have it on the ground yet because I haven't gotten to spend any time on it, plus I just needed to walk away for a bit. 

I used a Gates lower radiator hose that is/was close to the LS conversion hose and I think it's twisted enough to limit the coolant to the engine, the fans came on like they are supposed to but the temps was still climbing and when it showed 225 I shut it down.  I have a different hose to try this weekend.  The remaining issue is the clutch is being a PITA to get bled, I had this issue last year too.   It all just takes time!!!  As we all know!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Nexus on April 27, 2019, 10:54:09 AM
I'm just caught up from when you posted the video clip...does it ever sound smooth.....right on...won't be too long now!!!!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 30, 2019, 07:01:20 AM
I'm just caught up from when you posted the video clip...does it ever sound smooth.....right on...won't be too long now!!!!

Yes, It's run enough now that it settles in at around 1100 rpm idle and has a nice snappy sound to it!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on April 30, 2019, 07:08:32 AM
So, a couple posts ago I said that it was getting too hot after running for a while.  It heats up like it doesn't have coolant in it.  I did replace the lower radiator hose and now I believe that's not choking flow.  It still ran hot and I never saw anything circulating in the radiator and thought the tstat might be stuck closed.  Then I removed the Tstat and ran it again, this time it got hot just as before only it took a few more minutes to get hot.  Again, no circulation in the radiator. 

A bad water pump?
Is there some priming sequence I should have followed?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: Updated71 on May 01, 2019, 05:30:05 PM
Could it be an air pocket?
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on May 10, 2019, 07:22:02 AM
A brief update...  I replaced the water pump with one that I got from a good friend and after removing the Tstat again, that seems to allow it to run for extended periods of time while staying around 200F.  While this was going on I got to noticing that the Holley system doesn't seem to go into Closed loop mode.  It starts quickly and then idles for around 20 sec at 850-1000 rpm and then it slowly picks up rpm until it goes to 1500-1700 rpm and stays there.  The A/F says it's running at 11.5 and the learn % is 0.  I went back through the handheld to make sure I have learning clicked to "on" and 100%. I have the CTS set to 150 and both the coolant enable and rpm enable are set to "on".

Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on May 13, 2019, 06:51:01 AM
In my quest to get the engine to run in closed loop mode I poked around until it no longer starts again.  I thought for a bit that maybe I was having fuel pump problems but, no the fuel pump is working just fine.  It does start if I pour a bit of fuel manually down the TB, so the injectors aren't firing!
OMG- when does this BS stop? 

I know a lot of people have great experiences with their Holley EFI systems, I clearly am not in that category!  And I am not blaming all my woes on the Holley, every new part on this update has had one problem or another.

Vent paused for now...
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: FormTA on May 13, 2019, 08:13:31 AM
Wow, sorry the hear you are having all these issues with the swap. Kind of makes me glad I used the lame stock 1998 ecm with my LS swap. Good luck, I hope it is an easy fix for you.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on May 14, 2019, 06:59:19 AM
Wow, sorry the hear you are having all these issues with the swap. Kind of makes me glad I used the lame stock 1998 ecm with my LS swap. Good luck, I hope it is an easy fix for you.

I normally go the route you went Form, this time I wanted things to work the very first time and not have the regular trouble I have trying to get some used parts to work with other used parts.  Turns out, at least this time, that the new parts don't go together any better then the used parts.  I guess if this issue isn't a relay or some inexpensive part store piece, I can send it back to Holley and they will take care of it - that just means that it's on blocks for that much longer!
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on May 17, 2019, 11:15:56 AM
I'll trade you straight up for all my stock EFI stuff for your Holley stuff :cool:

Did you make sure that the IAC was within the 2-10 range? If not, you will need to adjust the throttle air blade position until you reach that range. It sounds to me like you are possibly either running out of the range for the IAC, or you are potentially running low on fuel pressure. Do you have a way to log your fuel pressure? And was it set to 58 PSI?

My Dad's Chevelle was doing the same thing with the idle that wouldn't go below 1300-1500 and it ended up being a combination of those two things. Also, the ECU won't go into closed loop until it's running within the parameters of your tune. So like my dad's for example wasn't learning since it wasn't getting hot enough. We had to fix that before it would learn.

Hope that helps.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on May 17, 2019, 12:10:44 PM
Oh and I re-read one of your earlier posts and this makes sense now. If you have a trapped air pocket, your temp sensor may be reading incorrectly and causing the ECU not to go into closed loop. I would try raising the front of your car up 12" or so and opening one of the front steam vents. That may help to relieve the pocket. You could also open the other 3 until antifreeze comes out to help with bleeding the system. What's nice is some of the earlier LS motors came with a 4 corner steam port that tied them all together and you can route them back into the radiator. That way it basically purges itself.
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: skisix38off on May 21, 2019, 07:31:59 AM
I'll trade you straight up for all my stock EFI stuff for your Holley stuff :cool:

Did you make sure that the IAC was within the 2-10 range? If not, you will need to adjust the throttle air blade position until you reach that range. It sounds to me like you are possibly either running out of the range for the IAC, or you are potentially running low on fuel pressure. Do you have a way to log your fuel pressure? And was it set to 58 PSI?

My Dad's Chevelle was doing the same thing with the idle that wouldn't go below 1300-1500 and it ended up being a combination of those two things. Also, the ECU won't go into closed loop until it's running within the parameters of your tune. So like my dad's for example wasn't learning since it wasn't getting hot enough. We had to fix that before it would learn.

Hope that helps.

I'll keep trying with this Holley stuff- Thanks tho!
The TPS is 0, and I thought that was the issue but, Ill go back to see the IAC value.  Fuel pressure is set to 42-44 psi which is what says in the manual..
Title: Re: LS376/515 swap in a '78 Trans Am
Post by: ryeguy2006a on May 21, 2019, 09:47:28 AM
I was kidding about swapping ECU's haha.

But you are right, on the 43 psi. I forget that you are running the terminator throttlebody on the LS engine. Keep me posted as we are having a little trouble with my dad's system too. He opted to swap from the large cap HEI to the small cap and when he did it's running terrible now... Trying to diagnose what is wrong with it to cause this issue.