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Author Topic: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits  (Read 67466 times)

scarebird

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #120 on: February 26, 2016, 07:19:49 PM »
Ours uses a 4" elbow, can send more pix if needed.


TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #121 on: June 07, 2016, 08:25:25 PM »
And for another update...

Been living with this swap for a few months now.  Have about 250 miles on this engine.  this thing pulls like a bear!  Its a really fun combo on the street...

One thing that bothers me is the decel exhaust crackling.  Under 2K rpm in an off throttle situation this thing crackles like hell.  Sounds like a combo of a backfire and a fart.  A loud fart.  Not happy with that sound at all.  All that I have read is this is a LS engine trait that can be tuned out with adding fuel in the off throttle situations, at a loss of 2-3 mpg.  Looks like I will have to live with the crackle until I can get this car on a dyno & get her tuned.

All the electrical gremlins have been addressed.  Loose grounds do funny things...

Still looking for a dyno & a tune closer to me.  No luck yet.

Took off a coil & a quarter.  While my stance is seriously now on the bitchen side, the tire does bottom out on the inner fender.  A quarter coil too much. I would seriously investigate updating the front & rear suspension, but I know darn well it would be stiffer & at this point I do not want that.

Still haven't messed around with the airbox.  Sounds like a plan for this winter...  LOL

All in all I am fairly happy with the way things have turned out.  Could be a lot worse! 
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

scarebird

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #122 on: June 07, 2016, 10:24:47 PM »
How did they run the exhaust?  Mine is transverse muffler, 2-1/2" inch using the Camaro exhaust manifolds and cats.

cal30_sniper

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #123 on: June 07, 2016, 11:08:04 PM »
It's not just an LS thing, it's a pretty common problem with a stick car with headers and fuel injection. It's caused by late combustion due to high manifold vacuum/low MAP. When you decel against the gearing, it creates pretty high manifold vacuum, leading to a very low density of the air/fuel mixture in the cylinder. Because the mixture is at such a low density, it has a very hard time combusting before it leaves the cylinder. This results in the combustion completing inside the hot exhaust header primary, leading to the dreaded pop. I fought it in the tune for weeks when I set up the Holley Stealth Ram/TPI Computer/T56 combo on my roommates 92 bird. I eventually found that a combination of spark advance (only under high vacuum/low MAP conditions) and a slight richening of the mixture at those levels got rid of 95% of the popping. The spark advance gives the mixture more time to combust inside the cylinder, and the richening of the mixture helps speed up the combustion enough that it happens inside the cylinder rather than inside the exhaust.

Many fuel injection systems offer a decel fuel cutoff mode. GM started doing it in 89 with the '165 TPI ECM. I'm sure the LS has something similar. If you can get that to kick in, it will solve your problem by removing the combustible mixture altogether under those conditions.
'73 Formula 350
'88 Trans Am GTA L98
'86 Suburban C20 454/NV4500

Formula build thread: http://transamcountry.com/community/index.php?topic=75375.msg705571#msg705571

TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #124 on: June 08, 2016, 01:19:39 AM »
How did they run the exhaust?  Mine is transverse muffler, 2-1/2" inch using the Camaro exhaust manifolds and cats.

I used Hedman 1 ¾” ceramic coated mid-length headers and Pypes Transverse 2.5" system.  No cats.

This exhaust package has a unique sound.  During regular driving, 3K and under (approx) there is a very nice mellow throaty sound.  Get into the throttle and it sounds like I have an exhaust cut out installed.  I like both sounds.  A sound for every occasion, so to speak.
« Last Edit: June 08, 2016, 01:34:52 AM by TransAm_Stan »
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #125 on: June 08, 2016, 01:29:53 AM »
It's not just an LS thing, it's a pretty common problem with a stick car with headers and fuel injection. It's caused by late combustion due to high manifold vacuum/low MAP. When you decel against the gearing, it creates pretty high manifold vacuum, leading to a very low density of the air/fuel mixture in the cylinder. Because the mixture is at such a low density, it has a very hard time combusting before it leaves the cylinder. This results in the combustion completing inside the hot exhaust header primary, leading to the dreaded pop. I fought it in the tune for weeks when I set up the Holley Stealth Ram/TPI Computer/T56 combo on my roommates 92 bird. I eventually found that a combination of spark advance (only under high vacuum/low MAP conditions) and a slight richening of the mixture at those levels got rid of 95% of the popping. The spark advance gives the mixture more time to combust inside the cylinder, and the richening of the mixture helps speed up the combustion enough that it happens inside the cylinder rather than inside the exhaust.

Many fuel injection systems offer a decel fuel cutoff mode. GM started doing it in 89 with the '165 TPI ECM. I'm sure the LS has something similar. If you can get that to kick in, it will solve your problem by removing the combustible mixture altogether under those conditions.

Thanks for the detailed explanation of whats going on with the "popping".  If I ever find someone who I trust to give me a ECU tune, believe me this decel tuning is first on my list.

I have been resisting the urge to try a hand at my own mapping.  I know it is a steep & expensive curve.  I just don't want to put in the time to learn this particular trade.  Plus risking the meltdown of my motor due to my incompetence is not a highly desirable outcome.  Since I can't find anyone close I might have to risk sending it away to a reputable tuner.  Any suggestions?
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

cal30_sniper

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #126 on: June 08, 2016, 08:05:51 AM »
It's not just an LS thing, it's a pretty common problem with a stick car with headers and fuel injection. It's caused by late combustion due to high manifold vacuum/low MAP. When you decel against the gearing, it creates pretty high manifold vacuum, leading to a very low density of the air/fuel mixture in the cylinder. Because the mixture is at such a low density, it has a very hard time combusting before it leaves the cylinder. This results in the combustion completing inside the hot exhaust header primary, leading to the dreaded pop. I fought it in the tune for weeks when I set up the Holley Stealth Ram/TPI Computer/T56 combo on my roommates 92 bird. I eventually found that a combination of spark advance (only under high vacuum/low MAP conditions) and a slight richening of the mixture at those levels got rid of 95% of the popping. The spark advance gives the mixture more time to combust inside the cylinder, and the richening of the mixture helps speed up the combustion enough that it happens inside the cylinder rather than inside the exhaust.

Many fuel injection systems offer a decel fuel cutoff mode. GM started doing it in 89 with the '165 TPI ECM. I'm sure the LS has something similar. If you can get that to kick in, it will solve your problem by removing the combustible mixture altogether under those conditions.

Thanks for the detailed explanation of whats going on with the "popping".  If I ever find someone who I trust to give me a ECU tune, believe me this decel tuning is first on my list.

I have been resisting the urge to try a hand at my own mapping.  I know it is a steep & expensive curve.  I just don't want to put in the time to learn this particular trade.  Plus risking the meltdown of my motor due to my incompetence is not a highly desirable outcome.  Since I can't find anyone close I might have to risk sending it away to a reputable tuner.  Any suggestions?

I haven't fooled with anything newer than OBDI, although I've thought about getting into it a few times. I would suggest against getting a mail order tune. If you've deviated much at all from stock, it just isn't likely to work out well. If you decide not to do it yourself, I'd take it to a shop that has good reviews and leave them to tune and drive it over the course of a week or so. Dyno tuning will get you down the track fast, but you need a good street tune to get rid of these kind of issues.

Personally, if I ever get an LS motor, I'll probably just get the stuff to tune it myself. Not really any more risk tuning a computer than tuning a carb/distributor combo as long as you are conservative with your inputs and know what each parameter controls. Just like using Microsoft Excel, anyone can do it, and most people can get pretty good at it with plenty of research and some experience.
'73 Formula 350
'88 Trans Am GTA L98
'86 Suburban C20 454/NV4500

Formula build thread: http://transamcountry.com/community/index.php?topic=75375.msg705571#msg705571

scarebird

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #127 on: June 08, 2016, 11:03:37 AM »
ah.  Mine has a nice crackle to it when decelerating; love it.  At idle it is dead quiet, but howls nicely when the spurs are put to it. 

A few years back I had a 2004 Trailblazer that I sent a spare PCM for a more performance oriented tune - gained a few horseys and another 2 mpg (14 to 16).  This for around $150.

cal30_sniper

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #128 on: June 08, 2016, 11:30:08 AM »
Suprisingly enough, it's a sign of a really good tune at low MAP. The closer I got my VE tables to stoichiometric, the worse the popping got. I've had the same thing happen with a well tuned quadrajet and free flowing exhaust backed up by a T56. The 454/Quadrajet/Headers/NV4500 in my Suburban also did it before I fattened up the jet/rod and idle mixture combination to about 12:1 with a closed throttle. No more popping at that point, but it took primary rods out of a 500 Cadillac with some honed out .080 jets to get it done. Those 80s truck carbs are set up for really large jet/rod combos.
'73 Formula 350
'88 Trans Am GTA L98
'86 Suburban C20 454/NV4500

Formula build thread: http://transamcountry.com/community/index.php?topic=75375.msg705571#msg705571

TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #129 on: September 25, 2017, 04:17:40 PM »
It has been awhile since I have checked in.  Not much has happened around here, to me, or the car.  Maintaining, so to speak.

I think I am going coil overs to try to get my front tire off of the inner fender on bumps. If I didn't cut off that extra quarter coil!  I have to do more research.  What I really need is a front rim with more back space. But that would be like the holy grail, since I am using Hurricanes.  I suppose I could go back to the stockers & see if that helps.

Anyhoo, I just wanted to say Hi to all my TA friends.  Several of you have been an invaluable source of information in my LS3, wet clutch,  Hydroboosted, 5 speed project.  Hats off to you.

Blue Skies.

Stan
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

T/A Addict

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #130 on: November 14, 2017, 04:57:02 AM »
Excellent stuff Stan, I'm going to refer back to this build often as I work through mine. Wish this forum had a subscribe to thread option like others.
Jeff
2016 Victory Cross Country
TATA '72 455 HO Auto
79 T/A 403 Solar Gold
69 F'Bird P-Touring T/A tribute to be
2010 Challenger R/T  PCP

TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #131 on: October 06, 2018, 08:12:30 AM »
Greetings Cats & Kittens!

It has been a year since I popped in & said hi to my TA friends.  I just wanted to give a little update to my thread.

This LS3 swap does not like cold weather.  Last winter I pulled it out of my heated garage where it lives, as I had to have the space for a temporary project. When I went to pull the car back in after several hours in high 20 degree temps, the car would not start. This has happened to me twice. Luckily the next day it was warmer & it fired right up. Got me stumped.

It has not been out at all this driving season, so I took it out last evening for a cruise around town.  My clutch is slipping a tad. I can feel & to some degree, hear it. (RPM's) I never was totally happy with the clutch from the first push of the pedal.  Any recommendations?  (LS3, wet clutch & a TKO5 speed)

Last year i believe, I went to pull the TA out of the garage & it would not start.  After much head scratching, I realized I could not hear the fuel pump in the tank like I normally do. WTF. I pulled the pump fuse in the box and low & behold the pump started working & the car fired right up. Sometimes the car gods do throw a bone at you occasionally!

Went back to the stock rims because I cut off a quarter too much off of my coils.  No more rubbing.  Still want coilovers, just have not got there yet. (procrastination, heavy!)

I have been out of the TA/LSX loop for awhile now. Any updates on a sender for the stock gauges?

My exhaust still pops & crackles on decel, it is rather embarrassing...  No flash or dyno tune yet either.

After I finished the install of this LS3 EROD, the instructions say take it to a chevy dealer & have the crankshaft position sensor relearn procedure done. I called them & they said (local chevy dealer) that they have no idea what I was talking about.  I just gave up on this procedure.

That is about all, going to go give my TA some love by changing the oil & filter!

Toodles..

Stan
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

scarebird

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #132 on: October 06, 2018, 02:02:27 PM »
My exhaust still pops & crackles on decel, it is rather embarrassing...  No flash or dyno tune yet either.

After I finished the install of this LS3 EROD, the instructions say take it to a chevy dealer & have the crankshaft position sensor relearn procedure done. I called them & they said (local chevy dealer) that they have no idea what I was talking about.  I just gave up on this procedure.

My TA crackles a bit too even with the crossflow muffler - I like it.

As far as the CASE relearn your Chevy dealership's service department are halfwits.  The coupon GM gives takes care of it, though it will help if you have a receipt for the EROD purchase.  This does need to get done.

TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #133 on: July 12, 2020, 03:48:11 PM »
Hey Kids!
 
Been awhile since I have poked my head in this forum.  Thought I would say hi!

Incidentally, I took my TA to a fairly local (30mi.) cruise in Saturday.  For some reason, the car did not seem to run very well.

For those of you that live near a fairly populated metropolis,  I envy you (to some degree, except with this Woo Tang Clan Virus!)! you have choices where & when you can get your car dyno tuned. Not available to me here in the sticks of WV.  I just have to travel too darn far for a tune. This is a backdrop for what is to come...

I have 95% decided to pull my ECU & harness and replace it with a Holly Terminator X setup.  Self learning to boot.  I think in the long run, this is my best option for getting a "tune".  Others may disagree, but they may have other options not available to me at this time, or ever.  Knowledgeable dyno shops close by, HP tuner knowledge or savvy mechanics that they trust etc. I have none of that available to me. This is my reason for the "upgraded" EFI controller & harness.  Plus the darn thing learns to boot!  To me it is a win win situation.
 
Some will say that it is pricey. I would tend to agree with that logic. But my time is worth something, and my head sez get it.

I will update when the kit rolls in.  I am calling Monday & ask questions...

Blue Skies!

Stausch
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

ryeguy2006a

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #134 on: July 13, 2020, 07:12:37 AM »
Glad to hear the car is still going. I swapped out my factory ECU and harness this past winter for a Terminator X and have been extremely happy with it. While it is very good at targeting the AFR for the engine, it is all based on some critical inputs from the user. One of which is the MAP sensor and the commanded AFR. You need to be certain that you have a functional MAP and that you are selecting the correct one when you build the tune. The other is your commanded AFR at idle, cruise and WOT. Holley has some great base tunes to start with, but you'll need to have an ECU and some basic tuning knowledge.

With that said, you can use the Wizard to build yourself a tune. The issue that I found with the Wizard was that it defaulted to the integrated internal MAP sensor, but I wanted to use my factory LS1 MAP, and it ran terrible until I figured that out. Since I didn't have anything hooked to it, the ECU thought I was at WOT and tried to compensate for that.

If I were you, I'd ensure that there is not something going on with your engine/tune/sensors etc before you go through the expense and time to remove and replace it with a Terminator X. You could have a pinhole leak in an exhaust tube that is causing false readings, or a IAT sensor that is failing where the engine thinks its 30* and adding fuel to compensate. Do you have access to a OBD2 reader with live data? If you do, make sure that all the sensors are functioning properly.

1976 Trans Am LS1, 6 speed, C5 Brakes, LS1 rear 12" brakes, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro LS6, T56, Speedtech, Hotchkis, DSE, Z51 13.4" front brakes, LS1 rear disks, etc.
http://transamcountry.com/community/index.php?topic=74591.0

Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #134 on: July 13, 2020, 07:12:37 AM »


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TransAm_Stan

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #135 on: July 13, 2020, 11:34:57 AM »
Glad to hear the car is still going. I swapped out my factory ECU and harness this past winter for a Terminator X and have been extremely happy with it. While it is very good at targeting the AFR for the engine, it is all based on some critical inputs from the user. One of which is the MAP sensor and the commanded AFR. You need to be certain that you have a functional MAP and that you are selecting the correct one when you build the tune. The other is your commanded AFR at idle, cruise and WOT. Holley has some great base tunes to start with, but you'll need to have an ECU and some basic tuning knowledge.

With that said, you can use the Wizard to build yourself a tune. The issue that I found with the Wizard was that it defaulted to the integrated internal MAP sensor, but I wanted to use my factory LS1 MAP, and it ran terrible until I figured that out. Since I didn't have anything hooked to it, the ECU thought I was at WOT and tried to compensate for that.

If I were you, I'd ensure that there is not something going on with your engine/tune/sensors etc before you go through the expense and time to remove and replace it with a Terminator X. You could have a pinhole leak in an exhaust tube that is causing false readings, or a IAT sensor that is failing where the engine thinks its 30* and adding fuel to compensate. Do you have access to a OBD2 reader with live data? If you do, make sure that all the sensors are functioning properly.

Good points Rye.
I do have a cheap dongle that I can try hooking up.  Excellent call.

This motor is a stock LS3 E-Rod motor.  It has 4  O2 sensors.  2 before and 2 after the cat. I am only using the 2 before and no cat.  I need the crank learning procedure (dealer has no clue). Too many issues against me with the stock ECU tune. I just need to move on.

Sounds like the Terminator X isn't as easy as it appears to be to get up & running.  Perfect...   :-?
76 White exterior, Blue interior "Toastee"
LS3, TKO600, Hydroboost
Hydraulic clutch
Western Hurricane rims

76 White 400 4sp. blue/white interior (project)
Can't get any more apart than I have it!

ryeguy2006a

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Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #136 on: July 13, 2020, 01:06:31 PM »
I'll bet both of those problems are a big part of your issues. I believe that the way those eRod combinations retain the 50 state legal status is to retain all of the factory emmissions, which the rear cats would be part of. Also if the Crank timing events are not synchronized, your car is likely running in some form of limp mode. Generally those kits are very turn key and ready to run.

Do you know anyone with HP tuners or EFI Live?? You can do the crank learning procedure using one of those software programs and you don't even have to license the ECU, so it doesn't cost. If not, do you have a buddy with a GM Tech2 scanner? They will do the same thing. If you do find someone with HP tuners or EFI Live, pay them to remove your rear O2 sensors too.

It's not that the Holley ECU isn't that easy to get up and running, but it is not a replacement for a good tune. I think the way that all of those self tuning ECU's are marketed is that you can set it and forget it, I just want you to know that isn't necessarily the case. There are so many parameters in the Holley ECU that could cause a bad tune, but the ECU will only make corrections on the main VE table. They don't change AFR, timing tables, idle tables, and etc. Then there are the numerous other things that the Terminator X Max has related to DBW ramp time, rates, and etc. What's nice is if you have a large cam, you can actually adjust the ramp speed, so say the first 30% of your pedal throw, you could adjust to 10% throttle blade opening to help with a bigger cam or save your tires, then the last 70% pedal throw would be pro-rated to the other 90%. Or any other combination that you can think up.

Then there are the programmable inputs and outputs. You can customize those anyway you choose which is a double edged sword. You have to program them as the only ones that come stock for outputs are fans and A/C disable. You can add inputs for VSS, or anything else you want. It is very robust, but can be intimidating.

Ok, so with all that said once I figured out that my ECU was looking at the wrong MAP sensor, it fired up immediately and figured out my base fueling right way. The learning doesn't start until your engine temp reaches 160*, and when I first got the car going I was cruising through town and it was popping a little through town. Once the temp was high enough, the tone of the exhaust changed and it instantly cleared up. After that it's run like a champ. The only thing that I'm not entirely happy with right now is a slight stumble/bog off idle once the car is hot. It's somewhere in the idle settings, but with 2 young kiddos I haven't had much time to play around with it more.

I should also mention that the car actually ran even though the ECU thought I had an enormous vacuum leak since it was reading 101 KPA all the time. It kept dumping fuel and allowed it run even with a critical sensor malfunction. Very impressive.

My advice would be to check out why your car isn't running correctly first with the eRod ECU and go from there. It may end up being something simple.

1976 Trans Am LS1, 6 speed, C5 Brakes, LS1 rear 12" brakes, and much more...SOLD
My Build: http://transamcountry.com/community/index.php?topic=24465.0

New project: 1968 Camaro LS6, T56, Speedtech, Hotchkis, DSE, Z51 13.4" front brakes, LS1 rear disks, etc.
http://transamcountry.com/community/index.php?topic=74591.0

Re: 1976 Trans Am: LS3 Swap, Hydraulic Clutch, TKO600 and other tidbits
« Reply #136 on: July 13, 2020, 01:06:31 PM »
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