Author Topic: LS3 Swap Project And Recommendations?  (Read 430 times)

beatboy77

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LS3 Swap Project And Recommendations?
« on: September 29, 2017, 09:30:42 AM »
I have a 77 TA and am about to start an LS3 swap in to it. Going with an LS3 with 6L90 Trans from a 2010 Camaro. MY TA still has the original rear end in it. Do you guys recommend a new rear end for this setup?

Josh

jonathonar89

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Re: LS3 Swap Project And Recommendations?
« Reply #1 on: September 29, 2017, 10:01:35 AM »
No, the 8.5 10 bolt in 2nd gen F-Body cars is a good rear end.  With proper modifications, it can handle a lot of power.  I've even read in a book one time, that if you do it up right, it can hold roughly 1000hp.  It's the late model 7.5 10 bolts that are weak.

One of the first things you should do is weld the axle tubes to the center section.  This is usually the first part to break on a 8.5 10 bolt.  The common upgrade for them after that, is switching to 30 spline center section and 30 spline axles...basically what came in later model trucks. 
1979 Trans Am 400 T-top - Platinum Silver, Carmine Interior
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beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #2 on: September 29, 2017, 11:38:23 AM »
No, the 8.5 10 bolt in 2nd gen F-Body cars is a good rear end.  With proper modifications, it can handle a lot of power.  I've even read in a book one time, that if you do it up right, it can hold roughly 1000hp.  It's the late model 7.5 10 bolts that are weak.

One of the first things you should do is weld the axle tubes to the center section.  This is usually the first part to break on a 8.5 10 bolt.  The common upgrade for them after that, is switching to 30 spline center section and 30 spline axles...basically what came in later model trucks.

Thank You!

I have heard the 6L80 Transmission is quite large and the floor of the TA will need to be modified heavily to fit. Is there another Transmission you recommend to mate with the LS3, which may be a better fit for a 77 TA?

Josh

jonathonar89

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Re: LS3 Swap Project And Recommendations?
« Reply #3 on: September 29, 2017, 01:28:46 PM »
No, the 8.5 10 bolt in 2nd gen F-Body cars is a good rear end.  With proper modifications, it can handle a lot of power.  I've even read in a book one time, that if you do it up right, it can hold roughly 1000hp.  It's the late model 7.5 10 bolts that are weak.

One of the first things you should do is weld the axle tubes to the center section.  This is usually the first part to break on a 8.5 10 bolt.  The common upgrade for them after that, is switching to 30 spline center section and 30 spline axles...basically what came in later model trucks.

Thank You!

I have heard the 6L80 Transmission is quite large and the floor of the TA will need to be modified heavily to fit. Is there another Transmission you recommend to mate with the LS3, which may be a better fit for a 77 TA?

Josh


Someone on here did the 6 speed auto.  He posted more on Facebook though.  That Trans work for him but the only issue I could possibly see was that the transmission pan hung slightly below the frame.  Most recommend a 4L80E or standard TH400/TH350 for LS engines.   I would try the 4L60E myself but that's me.
1979 Trans Am 400 T-top - Platinum Silver, Carmine Interior
http://transamcountry.com/community/index.php?topic=61460.0

beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #4 on: September 29, 2017, 01:53:30 PM »
No, the 8.5 10 bolt in 2nd gen F-Body cars is a good rear end.  With proper modifications, it can handle a lot of power.  I've even read in a book one time, that if you do it up right, it can hold roughly 1000hp.  It's the late model 7.5 10 bolts that are weak.

One of the first things you should do is weld the axle tubes to the center section.  This is usually the first part to break on a 8.5 10 bolt.  The common upgrade for them after that, is switching to 30 spline center section and 30 spline axles...basically what came in later model trucks.

Thank You!

I have heard the 6L80 Transmission is quite large and the floor of the TA will need to be modified heavily to fit. Is there another Transmission you recommend to mate with the LS3, which may be a better fit for a 77 TA?

Josh


Someone on here did the 6 speed auto.  He posted more on Facebook though.  That Trans work for him but the only issue I could possibly see was that the transmission pan hung slightly below the frame.  Most recommend a 4L80E or standard TH400/TH350 for LS engines.   I would try the 4L60E myself but that's me.

Thank You! I am doing the Hotchkis lowering kit, so I think that makes sense.

Josh


Re: LS3 Swap Project And Recommendations?
« Reply #4 on: September 29, 2017, 01:53:30 PM »

jonathonar89

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Re: LS3 Swap Project And Recommendations?
« Reply #5 on: September 29, 2017, 03:11:27 PM »
No, the 8.5 10 bolt in 2nd gen F-Body cars is a good rear end.  With proper modifications, it can handle a lot of power.  I've even read in a book one time, that if you do it up right, it can hold roughly 1000hp.  It's the late model 7.5 10 bolts that are weak.

One of the first things you should do is weld the axle tubes to the center section.  This is usually the first part to break on a 8.5 10 bolt.  The common upgrade for them after that, is switching to 30 spline center section and 30 spline axles...basically what came in later model trucks.

Thank You!

I have heard the 6L80 Transmission is quite large and the floor of the TA will need to be modified heavily to fit. Is there another Transmission you recommend to mate with the LS3, which may be a better fit for a 77 TA?

Josh


Someone on here did the 6 speed auto.  He posted more on Facebook though.  That Trans work for him but the only issue I could possibly see was that the transmission pan hung slightly below the frame.  Most recommend a 4L80E or standard TH400/TH350 for LS engines.   I would try the 4L60E myself but that's me.

Thank You! I am doing the Hotchkis lowering kit, so I think that makes sense.

Josh

Hotchkis is decent for bolt-on stuff.  Global West and Pro-Tourin F-Body are some other options for leaf spring setups.
1979 Trans Am 400 T-top - Platinum Silver, Carmine Interior
http://transamcountry.com/community/index.php?topic=61460.0

Old Chicken

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Re: LS3 Swap Project And Recommendations?
« Reply #6 on: September 29, 2017, 08:29:17 PM »
You are going to have trouble with that trans, they are huge.  I didn't want to cut up my tunnel so went with an LS1/4l60e out of an 04 GTO for my build.  Half wish I'd gone with the LS3/6060 manual trans combo but in the end the lazy side won out and stayed with the auto.  Going to have it built to hold the expected 500hp the mods will bring (forced injection).  If you use that trans please post some pics of what you did to make it work.

I'm going to have the original rear built with an aftermarket posi unit and probably better axles, cover, etc.  They are very usable with a little work.
« Last Edit: September 29, 2017, 08:33:01 PM by Old Chicken »

beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #7 on: October 01, 2017, 09:31:54 AM »
What is oil pan is recommended for an LS3 swap in to a 77 TA?

Thank You,

Josh

scarebird

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Re: LS3 Swap Project And Recommendations?
« Reply #8 on: October 01, 2017, 10:59:44 AM »
Supposedly the Holley pan is the hot ticket here.  I did an EROD changeover a couple years ago - the stock pan worked fine with minor grinding on the crossmember.  I plan to put a non-EROD crate in my 71 LeMans.

http://forums.maxperformanceinc.com/forums/showthread.php?t=718107&page=4

Lotta little stuff is the issue: radiator, pedal mount, etc.  We make a nice adapter for the pedal:

http://scarebird.com/index.php?route=product/product&path=96&product_id=163

jonathonar89

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Re: LS3 Swap Project And Recommendations?
« Reply #9 on: October 01, 2017, 11:28:31 AM »
Supposedly the Holley pan is the hot ticket here.  I did an EROD changeover a couple years ago - the stock pan worked fine with minor grinding on the crossmember.  I plan to put a non-EROD crate in my 71 LeMans.

http://forums.maxperformanceinc.com/forums/showthread.php?t=718107&page=4

Lotta little stuff is the issue: radiator, pedal mount, etc.  We make a nice adapter for the pedal:

http://scarebird.com/index.php?route=product/product&path=96&product_id=163


Does your adapter work with the supplied pedal they give you with that erod engine?
1979 Trans Am 400 T-top - Platinum Silver, Carmine Interior
http://transamcountry.com/community/index.php?topic=61460.0

78TA_In87

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Re: LS3 Swap Project And Recommendations?
« Reply #10 on: October 01, 2017, 12:53:33 PM »
What is oil pan is recommended for an LS3 swap in to a 77 TA?

Thank You,

Josh

Oil Pan:
Chevrolet Performance Engine Oil Pans 12628771
https://www.summitracing.com/parts/NAL-12628771
Oli pan pickup:
Chevrolet Performance Oil Pump Pickups 12558251

I have a shop almost done with my 78 erod connect and cruise.  Here's my build thread.  1st page has a parts list (Hope I have it up to date).
http://transamcountry.com/community/index.php?topic=76341.0
PONTIAC - We (Did) Build EXCITEMENT!!

scarebird

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Re: LS3 Swap Project And Recommendations?
« Reply #11 on: October 01, 2017, 08:44:30 PM »
Supposedly the Holley pan is the hot ticket here.  I did an EROD changeover a couple years ago - the stock pan worked fine with minor grinding on the crossmember.  I plan to put a non-EROD crate in my 71 LeMans.

http://forums.maxperformanceinc.com/forums/showthread.php?t=718107&page=4

Lotta little stuff is the issue: radiator, pedal mount, etc.  We make a nice adapter for the pedal:

http://scarebird.com/index.php?route=product/product&path=96&product_id=163


Does your adapter work with the supplied pedal they give you with that erod engine?

Yes.

beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #12 on: October 02, 2017, 06:14:41 AM »
What is oil pan is recommended for an LS3 swap in to a 77 TA?

Thank You,

Josh

Oil Pan:
Chevrolet Performance Engine Oil Pans 12628771
https://www.summitracing.com/parts/NAL-12628771
Oli pan pickup:
Chevrolet Performance Oil Pump Pickups 12558251

I have a shop almost done with my 78 erod connect and cruise.  Here's my build thread.  1st page has a parts list (Hope I have it up to date).
http://transamcountry.com/community/index.php?topic=76341.0

I like the look of that connect and cruise package. I noticed for the trans, it comes with the 4L65E. Does that fit in a 2nd Gen body without having to cut up the floor? Is it the same size as a 4L60E?

Josh


78TA_In87

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Re: LS3 Swap Project And Recommendations?
« Reply #13 on: October 02, 2017, 09:41:53 AM »
What is oil pan is recommended for an LS3 swap in to a 77 TA?

Thank You,

Josh

Oil Pan:
Chevrolet Performance Engine Oil Pans 12628771
https://www.summitracing.com/parts/NAL-12628771
Oli pan pickup:
Chevrolet Performance Oil Pump Pickups 12558251

I have a shop almost done with my 78 erod connect and cruise.  Here's my build thread.  1st page has a parts list (Hope I have it up to date).
http://transamcountry.com/community/index.php?topic=76341.0

I like the look of that connect and cruise package. I noticed for the trans, it comes with the 4L65E. Does that fit in a 2nd Gen body without having to cut up the floor? Is it the same size as a 4L60E?

Josh

No cutting was required. 
I'm not sure if they are the same size, but the 4L65E is the improved version so I am guessing the same or about the same.
PONTIAC - We (Did) Build EXCITEMENT!!

1981RoadRace

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Re: LS3 Swap Project And Recommendations?
« Reply #14 on: October 02, 2017, 09:55:57 AM »
Regarding the rear end, check out my thread. One thing to keep in mind is that the tube are steel and the center housing is iron. They do not weld together very easily. You will need someone who really knows what they are doing to pull this correctly -- there is a very long warm up and cool down process.

I don't have that level of skill or patience, and I ended up tapping and bolting my most recent housing with short grade 10.9 bolts. These were just long enough to go through the housing and tube, but not come in contact with the axle. I used one 12mm bolt on each side, with red lock tight. Works well, and dint require a lot of skill or patience. The housing has to be completely disassembled and cleaned before and after (you'd have to do the same for welding anyway).

I also put moser 7900fm axle ends on my rear diff, which eliminates the c-clips and converts the axle design to a ford style bolt in.
Karl R. - Editor, Silver Blade Magazine
2008 Grand Prix GXP | 1981 Trans Am WS6 - LS3, T56 + other bits of gearhead joy.


Re: LS3 Swap Project And Recommendations?
« Reply #14 on: October 02, 2017, 09:55:57 AM »

beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #15 on: October 03, 2017, 03:20:35 PM »
Just wanted to update that I ended up going with an LS3 crate engine from Jegs and a rebuilt 4L60 trans from Monster. Also got a lot of the parts from Muscle Rods. I will keep you updated as we progress through the build.

Josh

scarebird

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Re: LS3 Swap Project And Recommendations?
« Reply #16 on: October 03, 2017, 04:41:46 PM »
Just wanted to update that I ended up going with an LS3 crate engine from Jegs ...
Josh

Which one?  I am torn between the EROD 6.2 and the base non-emission version for my 71.


beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #17 on: October 03, 2017, 05:18:03 PM »
Just wanted to update that I ended up going with an LS3 crate engine from Jegs ...
Josh

Which one?  I am torn between the EROD 6.2 and the base non-emission version for my 71.



This one here

http://www.jegs.com/i/Chevrolet-Performance/809/19301326/10002/-1

Josh

scarebird

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Re: LS3 Swap Project And Recommendations?
« Reply #18 on: October 03, 2017, 08:07:09 PM »
mmnnh.

Old Chicken

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Re: LS3 Swap Project And Recommendations?
« Reply #19 on: October 03, 2017, 09:01:27 PM »
I'm using the F body pan, seems like that's what most of the Camaro second gen guys were using. You can get the whole kit on eBay, new GM with everything you need including the gasket and pick up tubes dipstick etc for I think around 350.  BRP has a real nice radiator for our cars with LS too, might want to take a look at... I think it's made by Dewitts.

78TA_In87

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Re: LS3 Swap Project And Recommendations?
« Reply #20 on: October 03, 2017, 09:37:35 PM »
I'm using the F body pan, seems like that's what most of the Camaro second gen guys were using. You can get the whole kit on eBay, new GM with everything you need including the gasket and pick up tubes dipstick etc for I think around 350.  BRP has a real nice radiator for our cars with LS too, might want to take a look at... I think it's made by Dewitts.

Yeah, I think that's the same pan i linked.  It's from GM and it's the one I am using.

And the radiator I got from BRP is made by DeWitts.  It even came with a Dewitts 40 page catalog.
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beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #21 on: October 04, 2017, 08:20:15 PM »
Can anyone share in detail what they have done for a rear end option when going to an LS3 type engine?

Josh


scarebird

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Re: LS3 Swap Project And Recommendations?
« Reply #22 on: October 04, 2017, 10:48:29 PM »
your 8.5 will be fine.

beatboy77

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Re: LS3 Swap Project And Recommendations?
« Reply #23 on: October 05, 2017, 10:10:55 AM »
your 8.5 will be fine.

Are any modifications needed for it to handle the 500HP?

Josh


scarebird

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Re: LS3 Swap Project And Recommendations?
« Reply #24 on: October 05, 2017, 07:59:45 PM »
I ran a Detroit Tru-Track with 31 spline axles.

Re: LS3 Swap Project And Recommendations?
« Reply #24 on: October 05, 2017, 07:59:45 PM »
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