87 Formula LS3 Swap
#1
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87 Formula LS3 Swap
With Christmas time and winter upon us it is time to start the winter project.
Last year my son and I did a GM crate engine swap / T-56 conversion into his 87 Formula keeping the TPI with the SDPC baseplate. Even though his Formula is in great shape it had 100K miles on it so in addition to the engine / tranny we took the time to update all the suspension, rear end, sub frame connectors, etc... What we did can be found in this posting
https://www.thirdgen.org/forums/engi...50-vortec.html
At the time we had debated LS swap but with my son being a senior in high school we also had the time crunch of making sure he was back running when good weather returned by end of April so we stuck with TPI and all the other upgrades
This year we are going to pull the TPI crate engine and LT1 T-56 out and put in a new crate LS3 and new Hawks supplied T-56 Magnum LS conversion tranny (has F body rear)
Since the pull out is basically new I will put that into another one of my 3rd gens at a future date... The pics are of our initial start-up last spring with the TPI crate engine / LT1 T-56 swap and what the engine bay and underneath look like as we start this winter's project
Last year my son and I did a GM crate engine swap / T-56 conversion into his 87 Formula keeping the TPI with the SDPC baseplate. Even though his Formula is in great shape it had 100K miles on it so in addition to the engine / tranny we took the time to update all the suspension, rear end, sub frame connectors, etc... What we did can be found in this posting
https://www.thirdgen.org/forums/engi...50-vortec.html
At the time we had debated LS swap but with my son being a senior in high school we also had the time crunch of making sure he was back running when good weather returned by end of April so we stuck with TPI and all the other upgrades
This year we are going to pull the TPI crate engine and LT1 T-56 out and put in a new crate LS3 and new Hawks supplied T-56 Magnum LS conversion tranny (has F body rear)
Since the pull out is basically new I will put that into another one of my 3rd gens at a future date... The pics are of our initial start-up last spring with the TPI crate engine / LT1 T-56 swap and what the engine bay and underneath look like as we start this winter's project
Last edited by alan91z28; 12-24-2016 at 09:34 AM.
#2
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Re: 87 Formula LS3 Swap
For this swap I also decided we would work with the Holley LS swap items. I like their dual exhaust and also the tranny mount that also holds the torque arm
However we have a little bit of work and learning to do using these components as from our upgrades last year we upgraded all the suspension including the k - member. The k - member is the UMI road race along with their a-arms. I have this set-up in three of my third gens so far and really like it.
The question with the holley LS swap items is they were originally designed for the stock k-member so we needed to do some investigation on any issues that we might face with our UMI k-member set-up
However we have a little bit of work and learning to do using these components as from our upgrades last year we upgraded all the suspension including the k - member. The k - member is the UMI road race along with their a-arms. I have this set-up in three of my third gens so far and really like it.
The question with the holley LS swap items is they were originally designed for the stock k-member so we needed to do some investigation on any issues that we might face with our UMI k-member set-up
#3
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Re: 87 Formula LS3 Swap
After some initial investigation with the Holley parts and the UMI k-member their was an issue that became obvious that needed to be solved.
I discussed with UMI the location of their engine mounts on their k member and they confirmed they are supposed to be in same position as stock k-member. This is important and also I know from installing several of these, for sbc installation you mount the stock isolator to the umi k-member and everything seems to line up great.
However when I got the Holley LS Swap Brackets an issue was soon apparent. They decided to largely use the V6 mounting holes present on the stock k-member but not present on the UMI piece (only has v8 location). Therefore I was thinking about just using the UMI LS conversion mounts that go with their k-member, however it soon became obvious from looking at the Holley mount vs UMI that Holley is positioning the LS engine further forward and slightly lower than what happens with the UMI LS engine mounts
We confirmed all this mounting / bolt pattern differences with a great template we had... the original k member
I discussed with UMI the location of their engine mounts on their k member and they confirmed they are supposed to be in same position as stock k-member. This is important and also I know from installing several of these, for sbc installation you mount the stock isolator to the umi k-member and everything seems to line up great.
However when I got the Holley LS Swap Brackets an issue was soon apparent. They decided to largely use the V6 mounting holes present on the stock k-member but not present on the UMI piece (only has v8 location). Therefore I was thinking about just using the UMI LS conversion mounts that go with their k-member, however it soon became obvious from looking at the Holley mount vs UMI that Holley is positioning the LS engine further forward and slightly lower than what happens with the UMI LS engine mounts
We confirmed all this mounting / bolt pattern differences with a great template we had... the original k member
#4
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Re: 87 Formula LS3 Swap
After comparing these two motor mounts and the issues we had discovered we had a couple of options
- just use the UMI LS mounts, but unlikely the Holley headers and tranny x-member would work out well as we know the Holley mounts are intentionally moving the engine forward to get some additional clearance
- modify the UMI LS mounts to have the mounting points in position like the holley... I was thinking of cutting the holley vertical portions off their mount and then welding them to the UMI LS mount base
- modify the Holley LS mount to have mounting provisions that would engage the V8 mounting holes present on the UMI k-member
In the end we went with the 3rd option as this was the easiest to line up with the template I made from the original k-member...
The pictures show the modification we made, basically welding 0.25" x 1.5" bar stock and then drilling per the template... You can see in the third picture the modified mounts in the middle vs stock UMI on top and stock Holley LS mount on bottom... Also you can notice on our modified mounts we took off the end v6 mounting provision as this will give additional clearance I believe for installing / removing the header with the UMI tubular k member and this combo
- just use the UMI LS mounts, but unlikely the Holley headers and tranny x-member would work out well as we know the Holley mounts are intentionally moving the engine forward to get some additional clearance
- modify the UMI LS mounts to have the mounting points in position like the holley... I was thinking of cutting the holley vertical portions off their mount and then welding them to the UMI LS mount base
- modify the Holley LS mount to have mounting provisions that would engage the V8 mounting holes present on the UMI k-member
In the end we went with the 3rd option as this was the easiest to line up with the template I made from the original k-member...
The pictures show the modification we made, basically welding 0.25" x 1.5" bar stock and then drilling per the template... You can see in the third picture the modified mounts in the middle vs stock UMI on top and stock Holley LS mount on bottom... Also you can notice on our modified mounts we took off the end v6 mounting provision as this will give additional clearance I believe for installing / removing the header with the UMI tubular k member and this combo
Last edited by alan91z28; 12-24-2016 at 10:03 AM.
#5
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Re: 87 Formula LS3 Swap
While the real test will be getting it mounted in the car, we did then also use a fit up engine with an extra UMI k member that I had to try our mounts out (note in these pics we hadn't yet trimmed the rear mounting hole off our modified mounts)
also confirmed with this versus my '85 IROC with a UMI k - member with UMI LS mounts and also the same holley oil pan we are using that the engine will be ~0.5" forward with the holley ls mount
also confirmed with this versus my '85 IROC with a UMI k - member with UMI LS mounts and also the same holley oil pan we are using that the engine will be ~0.5" forward with the holley ls mount
Last edited by alan91z28; 12-24-2016 at 10:11 AM.
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#8
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Re: 87 Formula LS3 Swap
won't cover much of the basic disassembly as there are plenty of threads showing that, but over the past couple days we pretty much got the ball rolling and got the exhaust, transmission, and engine out
we have a pretty good set-up for removal and install on the engine, we take the 3rd gen on the 4 post lift and roll it forward on a set of supports we made at the same height as our lift. we then have a gantry crane in front of the 4 post that the engine is lined up to once rolled onto the supports. this gives easy access to the under side of the car and easy pull out. once pulled out roll the car back unto the lift and lower the engine onto the stand... easy and safe
final things to clean up will be removal of the engine harness, the sbc motor mounts, and just a little clean up and then should be ready to start the LS work
we have a pretty good set-up for removal and install on the engine, we take the 3rd gen on the 4 post lift and roll it forward on a set of supports we made at the same height as our lift. we then have a gantry crane in front of the 4 post that the engine is lined up to once rolled onto the supports. this gives easy access to the under side of the car and easy pull out. once pulled out roll the car back unto the lift and lower the engine onto the stand... easy and safe
final things to clean up will be removal of the engine harness, the sbc motor mounts, and just a little clean up and then should be ready to start the LS work
#9
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Re: 87 Formula LS3 Swap
been a little slow on the updates, but we have been making progress...
first up was to prep the engine-
the crate motor that we are starting with is a standard GMPP LS3
it has the Chevy SS oil pan on it so we needed to get that changed out.
for the swap oil pan we went with the following
- Holley 302-2 LS F Body Oil Pan Kit
- GM 12558253 Oil Pan Windage Tray (modified per the holley 302-2 instructions)
- GM 12612350 Oil Pan Gasket
for the motor isolator mounts on the engine we started with new GM LS1 mounts and then added prothane inserts
- GM 22179268
- Prothane 7-512 Isolator Kit
first up was to prep the engine-
the crate motor that we are starting with is a standard GMPP LS3
it has the Chevy SS oil pan on it so we needed to get that changed out.
for the swap oil pan we went with the following
- Holley 302-2 LS F Body Oil Pan Kit
- GM 12558253 Oil Pan Windage Tray (modified per the holley 302-2 instructions)
- GM 12612350 Oil Pan Gasket
for the motor isolator mounts on the engine we started with new GM LS1 mounts and then added prothane inserts
- GM 22179268
- Prothane 7-512 Isolator Kit
#10
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Re: 87 Formula LS3 Swap
to mount the engine in the formula, the plan was to originally use the modified holley mounts with our UMI road race k-member
when we dropped the engine in, the mounts in the end just were not lining up as well as they did on the mock up. the drivers side mounted up well but the passenger side was off to the point that the point of contact and height of the stand just didn't seem right.
as my son is keenly interested in making sure his formula was ready to rip when good weather returns, we decided to alter course and save the holley components for another swap and go back to using the UMI mounts with hawks headers/exhaust vs the holley set-up
interestingly when we installed the UMI LS mount stands the engine seemed to sit a little far back to me. we reviewed this vs my '85 iroc and determined the present UMI LS mount stands (slider type) sit about 3/8" back in their most forward position compared to the earlier 4 through bolt UMI LS mount stands i have in my 85 iroc
while this would still work it pushed the engine back closer to the firewall and the shifter on the tranny pretty far back in the cut-out to the point we decided lets just modify the mount and use the slider feature to our advantage. to do this we made a jig off the original UMI slider mounts and moved the stands 1" forward. this allows plenty of adjustment and optimal engine placement. the UMI slider is a good idea and makes easy bolt up, just in the present form you can't really use the adjustment
with our modified UMI LS slider mount (posts 1" forward compared to original) we adjusted the engine to sit about 20mm (~.80") further forward. this gives nice firewall clearance, places the shifter in the center of the cutout and tranny mount in the forward portion of hawk's transmission swap mount
also while we didn't do this you could also now cut about 1" off the length of the UMI LS swap stand that would make header installation easier... more on this later, but to get in hawks 2" primary / 3" collector we needed to jack the engine up, which is relatively easy with the UMI set-up as just unbolt the stands, but also needed to remove the long through bolt and get the stands out of the way as the rear end of the stand even with the motor jacked up would hit the headers as they were going in
when we dropped the engine in, the mounts in the end just were not lining up as well as they did on the mock up. the drivers side mounted up well but the passenger side was off to the point that the point of contact and height of the stand just didn't seem right.
as my son is keenly interested in making sure his formula was ready to rip when good weather returns, we decided to alter course and save the holley components for another swap and go back to using the UMI mounts with hawks headers/exhaust vs the holley set-up
interestingly when we installed the UMI LS mount stands the engine seemed to sit a little far back to me. we reviewed this vs my '85 iroc and determined the present UMI LS mount stands (slider type) sit about 3/8" back in their most forward position compared to the earlier 4 through bolt UMI LS mount stands i have in my 85 iroc
while this would still work it pushed the engine back closer to the firewall and the shifter on the tranny pretty far back in the cut-out to the point we decided lets just modify the mount and use the slider feature to our advantage. to do this we made a jig off the original UMI slider mounts and moved the stands 1" forward. this allows plenty of adjustment and optimal engine placement. the UMI slider is a good idea and makes easy bolt up, just in the present form you can't really use the adjustment
with our modified UMI LS slider mount (posts 1" forward compared to original) we adjusted the engine to sit about 20mm (~.80") further forward. this gives nice firewall clearance, places the shifter in the center of the cutout and tranny mount in the forward portion of hawk's transmission swap mount
also while we didn't do this you could also now cut about 1" off the length of the UMI LS swap stand that would make header installation easier... more on this later, but to get in hawks 2" primary / 3" collector we needed to jack the engine up, which is relatively easy with the UMI set-up as just unbolt the stands, but also needed to remove the long through bolt and get the stands out of the way as the rear end of the stand even with the motor jacked up would hit the headers as they were going in
#11
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Re: 87 Formula LS3 Swap
for the transmission we are using a new T56 Magnum with the modification to have a F-body tail piece. Bruce (hawk's) supplied all of this in a complete nicely convenient package
as i had done my original LS swap in my '85 iroc back in '09 i forgot the lesson about the pilot bearing... out of habit of just getting mostly GM parts from my local deal i asked them for the pilot bearing for a 5th gen LS3 set-up in my parts list... of course this is the wrong pilot bearing in that it does not allow the longer shaft of the T56 f-body/magnum to fully seat, of course i re-learned this as we were trying to install the tranny
The parts we used
- T56 Magnum F Body Configuration from Hawks 2.66 ratio 1st gear
- New Tremec F-Body Bellhousing 1386-212-005
- Bellhousing / Flywheel covers GM24261713 / GM92169247
- Transmission Mount Prothane 7-1604
- Flywheel RAM1550 / Bolts GM 11569956
- Pilot Bearing GM 14061685 (small LS1 type!!!, not larger diam LS3 type!)
- Clutch RAM Powergrip 98931
- Slave Cylinder GM24264182
- Slave Cylinder Shims Tick, with instructions by Tick ~.216 clearance
- Master Hawks Adjustable kept from previous SBC/LT1 T56 swap from last year but changed output line to match LS slave
- Tick Slave Speed Bleeder
- Hawks LSX Swap Transmission Crossmember
as i had done my original LS swap in my '85 iroc back in '09 i forgot the lesson about the pilot bearing... out of habit of just getting mostly GM parts from my local deal i asked them for the pilot bearing for a 5th gen LS3 set-up in my parts list... of course this is the wrong pilot bearing in that it does not allow the longer shaft of the T56 f-body/magnum to fully seat, of course i re-learned this as we were trying to install the tranny
The parts we used
- T56 Magnum F Body Configuration from Hawks 2.66 ratio 1st gear
- New Tremec F-Body Bellhousing 1386-212-005
- Bellhousing / Flywheel covers GM24261713 / GM92169247
- Transmission Mount Prothane 7-1604
- Flywheel RAM1550 / Bolts GM 11569956
- Pilot Bearing GM 14061685 (small LS1 type!!!, not larger diam LS3 type!)
- Clutch RAM Powergrip 98931
- Slave Cylinder GM24264182
- Slave Cylinder Shims Tick, with instructions by Tick ~.216 clearance
- Master Hawks Adjustable kept from previous SBC/LT1 T56 swap from last year but changed output line to match LS slave
- Tick Slave Speed Bleeder
- Hawks LSX Swap Transmission Crossmember
#12
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Re: 87 Formula LS3 Swap
with the motor mounts resolved and transmission mounted we received from bruce his very nice LS swap exhaust. this Hawks / Stainless Works exhaust has 2" primaries with 3" collector along with complete y-pipe and 3.5" muffler input / single output and comes as one complete kit
as mentioned above, to get the large headers in we needed to loosen all the motor mounts jack the engine up and then install the headers. once installed everything fit very well on the headers with the engine bolted down in the position noted above
as mentioned above, to get the large headers in we needed to loosen all the motor mounts jack the engine up and then install the headers. once installed everything fit very well on the headers with the engine bolted down in the position noted above
#13
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Re: 87 Formula LS3 Swap
Those headers are too big for an LS3 and you're going to lose torque across nearly the entire power band. Suggest you see if you can trade for smaller primary tubes.
For what it is worth, my headers (same kind) went in easy after removing the oil filter. Didn't need to lift the engine.
For what it is worth, my headers (same kind) went in easy after removing the oil filter. Didn't need to lift the engine.
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Re: 87 Formula LS3 Swap
Looks good. You are going to be happy with the power it makes.
Glad to see you installed the remote bleeder for the slave cylinder. Found about that the hard way when I could not get to the factory bleeder screw.
Glad to see you installed the remote bleeder for the slave cylinder. Found about that the hard way when I could not get to the factory bleeder screw.
#16
Re: 87 Formula LS3 Swap
I have an LS2 powered thirdgen, PRC227 heads, MS4 cam, tick level 5 tr6060 magnum and I was recommended the 1 7/8" primary to 3" hawks by Texas Speed.
I highly doubt 1/8" bigger will make you lose anything noticeable. You're talking .125" difference in diameter.
Good luck with the project, these cars with LS engines and SFCs are no joke.
I highly doubt 1/8" bigger will make you lose anything noticeable. You're talking .125" difference in diameter.
Good luck with the project, these cars with LS engines and SFCs are no joke.
#17
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Re: 87 Formula LS3 Swap
Those headers are too big for an LS3 and you're going to lose torque across nearly the entire power band. Suggest you see if you can trade for smaller primary tubes.
For what it is worth, my headers (same kind) went in easy after removing the oil filter. Didn't need to lift the engine.
For what it is worth, my headers (same kind) went in easy after removing the oil filter. Didn't need to lift the engine.
Curious on your header install, what k-member and mounting plates are you using... my issue is for example i couldn't get around the bellhousing and the back of the UMI motor mount plate at the same time... although since we have a lift and can easily move the engine up after trying it a couple times we just made it easy on ourselves. in the past i was able to install these headers with the bmr k member without lifting the engine, but the bmr sits the engine higher to start with and when i swapped the umi k member into that 85 iroc of course the headers were already in, so this was our first try with this complete combination
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Re: 87 Formula LS3 Swap
Good call, yes I have the BMR k-member. Wouldn't have guessed that it would make that much difference!
#20
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Re: 87 Formula LS3 Swap
Been busy and behind on posting progress... My son went back to Penn State so I am down my good partner at this point, but he wants his Formula ready to go for spring so I soldier on at this point!
So one of the things that I have been going back and forth on is torque arm mounting...
- mounting to the tailshaft is out, I have seen too many broken t-56 that way so won't consider it
- looked at doing a tunnel mounted torque arm like the jegster I have in my '85 IROC and bought the steinjager unit. it is generally nice but the axle mount is only made for the 10 bolt so would have to fab something up for the 8.8 in this Formula so before I did that I started thinking about other options
- also have a cross sub frame mounted short torque arm kit and thought about that but worried about ground clearance as I did not like this type when installed in my 85 IROC (why I went jegster)... thought about making a loop in it for the exhaust to pass through but worried about other clearance issues to driveshaft and also still ground clearance
- went back and looked at the Holley LSX swap cross member I bought with the integrated torque arm mounting and decided I was going to use that even though not using their motor mounts or exhaust at this point
I really like the Holley piece, in the end they could make it more user friendly for bigger exhausts like I am running by simply making some minor geometry changes to their center section, but I was able to make it work
A couple specific things I needed to do with my set up which again is using the UMI K Member with my modified UMI motor mounts, T56 magnum with F body tailshaft and also going to a Hawks 8.8 rear
- The customized UMI motor mount brackets I made worked great pushing the engine forward as noted so the Holley cross member was in the right spot for the rear of the transmission, would not have been with original UMI position
- For the T-56 transmission rear isolator mount I needed to use the Energy Suspension 3.1158R which is 0.25" shorter to avoid the T-56 hitting the tunnel on top... (holley cross member pushes transmission higher than hawks swap cross member and the UMI motor mount puts the engine a little higher than what the holley mount would appear to)
- The position of my torque arm which is a UMI 1.25" tube type transmission mount, likely due to the rear position mount with the 8.8 meant I needed to shim out ~0.5" towards the center the forward mounting position on the Holley cross member to give adequate clearance to the torque arm in the tunnel. I had made 0.120" stainless shims so I could decide on the right fit for my situation. To get the shims to fit I needed to cut down the torque arm mounting boss on the T-56 tailshaft which isn't used... Also it would be great to ditch the reverse lock out solenoid which I am not using but it did all fit with it in place
- I also shortened the UMI torque arm at the front nose by ~15mm as it was very close to the speed sensor with almost no clearance. Cut it off and plugged the end with 1.0" rod
After these adjustments everything seemed to fit well
So one of the things that I have been going back and forth on is torque arm mounting...
- mounting to the tailshaft is out, I have seen too many broken t-56 that way so won't consider it
- looked at doing a tunnel mounted torque arm like the jegster I have in my '85 IROC and bought the steinjager unit. it is generally nice but the axle mount is only made for the 10 bolt so would have to fab something up for the 8.8 in this Formula so before I did that I started thinking about other options
- also have a cross sub frame mounted short torque arm kit and thought about that but worried about ground clearance as I did not like this type when installed in my 85 IROC (why I went jegster)... thought about making a loop in it for the exhaust to pass through but worried about other clearance issues to driveshaft and also still ground clearance
- went back and looked at the Holley LSX swap cross member I bought with the integrated torque arm mounting and decided I was going to use that even though not using their motor mounts or exhaust at this point
I really like the Holley piece, in the end they could make it more user friendly for bigger exhausts like I am running by simply making some minor geometry changes to their center section, but I was able to make it work
A couple specific things I needed to do with my set up which again is using the UMI K Member with my modified UMI motor mounts, T56 magnum with F body tailshaft and also going to a Hawks 8.8 rear
- The customized UMI motor mount brackets I made worked great pushing the engine forward as noted so the Holley cross member was in the right spot for the rear of the transmission, would not have been with original UMI position
- For the T-56 transmission rear isolator mount I needed to use the Energy Suspension 3.1158R which is 0.25" shorter to avoid the T-56 hitting the tunnel on top... (holley cross member pushes transmission higher than hawks swap cross member and the UMI motor mount puts the engine a little higher than what the holley mount would appear to)
- The position of my torque arm which is a UMI 1.25" tube type transmission mount, likely due to the rear position mount with the 8.8 meant I needed to shim out ~0.5" towards the center the forward mounting position on the Holley cross member to give adequate clearance to the torque arm in the tunnel. I had made 0.120" stainless shims so I could decide on the right fit for my situation. To get the shims to fit I needed to cut down the torque arm mounting boss on the T-56 tailshaft which isn't used... Also it would be great to ditch the reverse lock out solenoid which I am not using but it did all fit with it in place
- I also shortened the UMI torque arm at the front nose by ~15mm as it was very close to the speed sensor with almost no clearance. Cut it off and plugged the end with 1.0" rod
After these adjustments everything seemed to fit well
#21
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Re: 87 Formula LS3 Swap
The driveshaft is a little special when dealing with the T-56 magnum with the F-Body tailshaft.
The T-56 magnum uses a 31 spline output shaft for additional strength. The issue that you need to watch out for is when you get the magnum in with the F Body tailshaft configuration it requires a special modified 31 spline slip yoke as the standard slip yoke is now too long in terms of spline length compared to the output shaft set-up in this f-body special config...
When I originally got my driveshaft it had the standard Sonnax 31 spline T-56 magnum slip yoke and I couldn't get it to slide in, after some research I found this issue of needing the special slip yoke which basically removes about ~1 5/8" of the initial spline
With this special yoke everything now fits up great and I adjusted my pinion angle to ~ - 2.75 deg
For reference in my son's Formula our measurements for the driveshaft where 44.375" from face of the 8.8 yoke to the rear face of the T-56 and the T-56 has 0.77" of output shaft exposed from the rear face of the tranny
Bruce at Hawks was great in getting this all sorted out and is the top notch resource as always!
The T-56 magnum uses a 31 spline output shaft for additional strength. The issue that you need to watch out for is when you get the magnum in with the F Body tailshaft configuration it requires a special modified 31 spline slip yoke as the standard slip yoke is now too long in terms of spline length compared to the output shaft set-up in this f-body special config...
When I originally got my driveshaft it had the standard Sonnax 31 spline T-56 magnum slip yoke and I couldn't get it to slide in, after some research I found this issue of needing the special slip yoke which basically removes about ~1 5/8" of the initial spline
With this special yoke everything now fits up great and I adjusted my pinion angle to ~ - 2.75 deg
For reference in my son's Formula our measurements for the driveshaft where 44.375" from face of the 8.8 yoke to the rear face of the T-56 and the T-56 has 0.77" of output shaft exposed from the rear face of the tranny
Bruce at Hawks was great in getting this all sorted out and is the top notch resource as always!
#22
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Re: 87 Formula LS3 Swap
Great work, as always!
If you ever need extra stainless T-bolts, I have a few, $10 ea. + ship.
If you ever need extra stainless T-bolts, I have a few, $10 ea. + ship.
#23
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Re: 87 Formula LS3 Swap
#24
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Re: 87 Formula LS3 Swap
For cooling debated a little bit on what radiator to use, but for this swap decided to go with the Flex-a-lite 82-92 Camaro / Firebird Radiator and Fan Combo, it is a 2 row with dual 3000 cfm fans and shroud... it looked like a nice integrated unit so decided to give it a try
The part number we are utilizing is Flex-a-lite 56484DS.
It is supposed to be a direct fit and for the most part it is. It uses up all available space so it is a little tight getting it in (steering box is the tightest part) but does seem to fit well once in.
You need to trim do the stock rubber isolator bottom pads flat which is easy to do with a sharp utility knife even with them still in position with the condenser installed
For the top mounting they supply a bracket that bolts to top of the radiator and then to the usual top radiator piece mounting points... the radiator we received didn't have the top mounting points installed so we are going to do something different that I think will work out better (more on that latter once I get the parts made)
For the radiator lower hose connection to the LS3 water pump thermostat, used the Dayco 71321 and cut to fit. To make sure no collapsing of the hose I did also insert a 35mm (1 3/8") alum splice tube from Pegasus Auto and held it in place with a Power Grip (32948) to keep the hose shape and give a little additional wear protection. For the clamp on the bottom used a stainless steel hose clamp as it is close to the rail so need a thin clamp. For the water pump side I used a constant pressure clamp, GM 13136147
For the radiator top hose connection to the LS3 water pump I made my own hose out of two to get a nice good fit on both ends. On the pump side used a Continental 62426 and for the radiator side used a Continental 61025. Trimmed these to meet in the middle and spliced them together using a 32mm (1 1/4) aluminum hose spline from Pegasus with a Power Grip (32941). For clamps I utilized a constant pressure clamp GM 13136147 on the radiator side and constant pressure clamp GM 11516234 on the pump side
Also installed a zinc anode for protection in the radiator drain port, Flex-a-lite 32060
The part number we are utilizing is Flex-a-lite 56484DS.
It is supposed to be a direct fit and for the most part it is. It uses up all available space so it is a little tight getting it in (steering box is the tightest part) but does seem to fit well once in.
You need to trim do the stock rubber isolator bottom pads flat which is easy to do with a sharp utility knife even with them still in position with the condenser installed
For the top mounting they supply a bracket that bolts to top of the radiator and then to the usual top radiator piece mounting points... the radiator we received didn't have the top mounting points installed so we are going to do something different that I think will work out better (more on that latter once I get the parts made)
For the radiator lower hose connection to the LS3 water pump thermostat, used the Dayco 71321 and cut to fit. To make sure no collapsing of the hose I did also insert a 35mm (1 3/8") alum splice tube from Pegasus Auto and held it in place with a Power Grip (32948) to keep the hose shape and give a little additional wear protection. For the clamp on the bottom used a stainless steel hose clamp as it is close to the rail so need a thin clamp. For the water pump side I used a constant pressure clamp, GM 13136147
For the radiator top hose connection to the LS3 water pump I made my own hose out of two to get a nice good fit on both ends. On the pump side used a Continental 62426 and for the radiator side used a Continental 61025. Trimmed these to meet in the middle and spliced them together using a 32mm (1 1/4) aluminum hose spline from Pegasus with a Power Grip (32941). For clamps I utilized a constant pressure clamp GM 13136147 on the radiator side and constant pressure clamp GM 11516234 on the pump side
Also installed a zinc anode for protection in the radiator drain port, Flex-a-lite 32060
Last edited by alan91z28; 02-28-2017 at 05:53 PM.
#25
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#26
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Re: 87 Formula LS3 Swap
For the fan wiring used two Spal SPU-IX-185FH kits... these will be driven by the LS ECM so did not use the thermal switch that was in the kit.
To connect to the fans that come with loose wiring, I used Spal Metri Pack 280 pigtails (female connector) SPU-XFRPT1530027 on the relay wiring side and then mated them with corresponding male connectors I made with a tray kit
For power we will be getting the power from the starter stud. Put a fusible link off the starter stud (note pic does not have wiring tied back yet so just for illustration) that connects to both relay feed wires and then mounted the included fuse right before connection to the relay.
This made for an easy to wire up connection that should be easy to control and have a good separate and protected power source
To connect to the fans that come with loose wiring, I used Spal Metri Pack 280 pigtails (female connector) SPU-XFRPT1530027 on the relay wiring side and then mated them with corresponding male connectors I made with a tray kit
For power we will be getting the power from the starter stud. Put a fusible link off the starter stud (note pic does not have wiring tied back yet so just for illustration) that connects to both relay feed wires and then mounted the included fuse right before connection to the relay.
This made for an easy to wire up connection that should be easy to control and have a good separate and protected power source
#27
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Re: 87 Formula LS3 Swap
Over the past month made quite a bit of progress, just been busy so haven't posted up as I should be. I would try and catch back up over the next week...
The exhaust is all in and done. It is based on Hawks Stainless Works 2" primary, 3" y-pipe, and 3.5" back complete system.
A number of mods had to be done to the front section and also to the long 3.5" pipe to allow it to fit around the hooker cross member and also to accommodate a pair of high flow cats.
All in all it wasn't too bad, the pics give you a good idea of what I did. I ended up putting a vibrant performance bellow in the passenger side of the y-pipe. Since I cut it all up anyways I wanted to give this a try to see if it cuts down on the expansion / contraction noise that is typical in these merge type of systems
The long 3.5" pipe I shortened by ~5.5 inches and used the rear part of the Hawks Y-pipe to fit to it so that gives a good idea of the stretch needed in the y-pipe regardless of cats or not to fit the hawks exhaust with the hooker cross member
The high flow cats I used were DynaTech Power Cat 77940030
The bellow is Vibrant 68834 which is a 3.02" diam by 4" long bellow
The exhaust is all in and done. It is based on Hawks Stainless Works 2" primary, 3" y-pipe, and 3.5" back complete system.
A number of mods had to be done to the front section and also to the long 3.5" pipe to allow it to fit around the hooker cross member and also to accommodate a pair of high flow cats.
All in all it wasn't too bad, the pics give you a good idea of what I did. I ended up putting a vibrant performance bellow in the passenger side of the y-pipe. Since I cut it all up anyways I wanted to give this a try to see if it cuts down on the expansion / contraction noise that is typical in these merge type of systems
The long 3.5" pipe I shortened by ~5.5 inches and used the rear part of the Hawks Y-pipe to fit to it so that gives a good idea of the stretch needed in the y-pipe regardless of cats or not to fit the hawks exhaust with the hooker cross member
The high flow cats I used were DynaTech Power Cat 77940030
The bellow is Vibrant 68834 which is a 3.02" diam by 4" long bellow
#28
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Re: 87 Formula LS3 Swap
For securing the top of the radiator we ended up making our own bracket out of stainless
Had a channel and also a flat made up that can mate to the channel at the appropriate angle that had securement holes matching the original mounting location
The pics show how we constructed the bracket by welding the two pieces together at the correct angle and then also added some 1/8" isolator channel silicone rubber (McMaster-carr) to provide the dampening between the bracket and the radiator
Had a channel and also a flat made up that can mate to the channel at the appropriate angle that had securement holes matching the original mounting location
The pics show how we constructed the bracket by welding the two pieces together at the correct angle and then also added some 1/8" isolator channel silicone rubber (McMaster-carr) to provide the dampening between the bracket and the radiator
#30
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Re: 87 Formula LS3 Swap
No, I had both pieces custom made
Both are made from 14 gauge stainless... could have made it from aluminum but stainless is easier to work with for me. My friend Rich is a great TIG welder which is a big help!
The channel is 24" long with an inside width of 2.71" and an inside height of .88 inches
The support piece matches the 24" then flares out. The spacing of the hole slots matches the car at 225mm
Last edited by alan91z28; 04-01-2017 at 06:12 AM.
#31
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Re: 87 Formula LS3 Swap
On the steam venting for the LS3 I kept going back and forth on what I was going to do.
However I settled on what I think is a very easy and very good system that also provides some nice capability.
As you saw in one of my previous posts above I custom made our top rad hose with a splice in the middle
Stealth Conversions (Jags that Run) makes a nice splice that allows a nipple for the steam tube connection and also has a drain **** for easier fill and air bleeding of the system.
I installed their 1 5/16 LS Aluminum Splicer set-up using two Power Grips (32941) in place of my original splice
This makes for a very nice and high steam port connection and what I think will be a nice way to fill and bleed of any air in the system
However I settled on what I think is a very easy and very good system that also provides some nice capability.
As you saw in one of my previous posts above I custom made our top rad hose with a splice in the middle
Stealth Conversions (Jags that Run) makes a nice splice that allows a nipple for the steam tube connection and also has a drain **** for easier fill and air bleeding of the system.
I installed their 1 5/16 LS Aluminum Splicer set-up using two Power Grips (32941) in place of my original splice
This makes for a very nice and high steam port connection and what I think will be a nice way to fill and bleed of any air in the system
#32
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Re: 87 Formula LS3 Swap
For the PCV a couple of things were done
On the dirty side (ie port from the valley cover) used an Elite Engineering LS3 Camaro catch can mounted to the passenger head. For fittings I used Earl's 90 degree fitting AT984206ERL on the top and straight fitting AT984006ERL on the side. Connected the top fitting to the valley cover fitting and the side fitting to the manifold. Both with 3/8" emissions hose
For the valve cover ports, blocked off both the driver and passenger ports and have a Central Florida Motorsports (CFM) oil fill cap one way breather installed. This breather only lets pressure out. The breather is their 1-0201-2 that is made for 98-02 and 10-15 4th and 5th gen Camaros
On the dirty side (ie port from the valley cover) used an Elite Engineering LS3 Camaro catch can mounted to the passenger head. For fittings I used Earl's 90 degree fitting AT984206ERL on the top and straight fitting AT984006ERL on the side. Connected the top fitting to the valley cover fitting and the side fitting to the manifold. Both with 3/8" emissions hose
For the valve cover ports, blocked off both the driver and passenger ports and have a Central Florida Motorsports (CFM) oil fill cap one way breather installed. This breather only lets pressure out. The breather is their 1-0201-2 that is made for 98-02 and 10-15 4th and 5th gen Camaros
#33
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Re: 87 Formula LS3 Swap
Great job on the exhaust. What CATS did you go with? This exactly how I will be crafting my y-pipe. Any reason you went with the 2" primaries?
#34
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Re: 87 Formula LS3 Swap
Man this is a well thought out project. Still working on my LQ9 in my '92. Haven't had time since Christmas to touch it but I still walk out into the garage and wipe its nose to let it know I've not forgotten about it. Whose "Y" pipe is that? Looks nice.
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Car: '87 IROC-Z | '99 SS
Engine: LB9 | LS1
Transmission: 700R4 | T56
Re: 87 Formula LS3 Swap
Great thread... taking notes for my swap. Had you ever reached Holley about the fitment of the engine mounts and the K-member?
#36
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Re: 87 Formula LS3 Swap
The CATS we used are DynaTech Power Cat 77940030
I have this same exhaust (minus the Cats) on my 85 IROC and I like the way it fits, the sound, etc and it is a nice complete kit so we decided to use it as well on this swap
#37
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Re: 87 Formula LS3 Swap
The Y-pipe is a modified version of the Y-pipe that comes with the complete Hawks / Stainless Works exhaust kit we used. It is headers all the way to muffler / tailpipe. We had to adapt the center section to fit the Cats and work with the Holley Cross Member, etc
#38
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Re: 87 Formula LS3 Swap
No I haven't yet, although I have talked to UMI about the adaption to the motor mount that I made based on their set-up and believe they have or will be incorporating my suggestion to them
#39
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Re: 87 Formula LS3 Swap
For the air intake tube we used the AIRAID AID-100-400 4" U Build It Intake Tube.
It is a nice kit that is very easy to work with and allows a clean finished look that also keeps the air cooler versus aluminum tube
From the AIRAID kit we utilized basically 2 sections
- 90 deg to straight with a 10" straight section
- 45 deg angle
For the MAF section we utilized a AIRAID 9641 MAF Adapter
The filter set-up we utilized was aFe Filter 24-40035
For connectors utilized AIRAID 9216 and 9019 for tube and throttle body connections respectively
It is a nice kit that is very easy to work with and allows a clean finished look that also keeps the air cooler versus aluminum tube
From the AIRAID kit we utilized basically 2 sections
- 90 deg to straight with a 10" straight section
- 45 deg angle
For the MAF section we utilized a AIRAID 9641 MAF Adapter
The filter set-up we utilized was aFe Filter 24-40035
For connectors utilized AIRAID 9216 and 9019 for tube and throttle body connections respectively
#40
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Re: 87 Formula LS3 Swap
We have done a lot more over the last month to get the Formula ready to drive that I will need to catch up and post, but we were able to get it cranked and started about 2 weeks ago.
The great thing is that on the base tune I made it started the first turn of the key immediately!
Here is a quick video of one of our first runs in the driveway
We have since gotten it all buttoned up and had a couple quick runs on the street... So far my son is liking where we are going with it!
The great thing is that on the base tune I made it started the first turn of the key immediately!
Here is a quick video of one of our first runs in the driveway
We have since gotten it all buttoned up and had a couple quick runs on the street... So far my son is liking where we are going with it!
The following 2 users liked this post by alan91z28:
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#42
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Car: '89 Firebird
Engine: 7.0L
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Re: 87 Formula LS3 Swap
I have the same exhaust system on my car. Those cats really tame down the noise to a nice level without giving up the deep tone. Makes me think about installing some cats just for the noise control. My car is too loud and my ears hurt sometimes -- not good!
#43
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Re: 87 Formula LS3 Swap
I have had some guys ask about dimensional location for the clutch master cylinder firewall holes.
Here is the dimensions I have been using. They compare the newly needed holes to the centerline of two of the existing steering column firewall mounting bolts/holes. These originally come from measurements I took off my factory 5-speed 85 IROC.
I use a compass to get intersecting lines and I also make a doubler plate first (which you can place against your master cylinder outside the car so you know your holes are right in the doubler) that I then line up against the firewall to make sure everything is completely right before I drill.
Here is the dimensions I have been using. They compare the newly needed holes to the centerline of two of the existing steering column firewall mounting bolts/holes. These originally come from measurements I took off my factory 5-speed 85 IROC.
I use a compass to get intersecting lines and I also make a doubler plate first (which you can place against your master cylinder outside the car so you know your holes are right in the doubler) that I then line up against the firewall to make sure everything is completely right before I drill.
#45
#47
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Re: 87 Formula LS3 Swap
https://www.thirdgen.org/forums/engi...50-vortec.html
5/8 hose was a combination of (from firewall to engine)
- 5/8 molded 90 deg hose continental 63824 cut to fit
- connected by hose splice continental 65624 with two gates powergrip 32925
- 5/8 molded 90 deg hose continental 63824 cut to fit
3/4 hose was a combination of (from firewall to engine)
- 3/4 molded 90 degree continental 63912 cut to fit
- connected by hose splice Help 47095 with gates powergrip 32929 & 32925
- 3/4 molded 90 degree dayco 8040 cut to fit
i covered them with hot rod sleeving #204018 from heatshield products
https://www.summitracing.com/nv/part...4018/overview/
Last edited by alan91z28; 04-25-2018 at 07:46 PM.
#48
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Re: 87 Formula LS3 Swap
In general my son has really enjoyed this swap... we have really progressed this formula over the last several years from its original L98 / 700r to a TPI vortec ZZ5 / T56 to the LS3 / T56
Clearly the LS3 / T56 combo is really wonderful... great performance, fuel economy, and reliability
We still have further updates in the future we will be doing. At some point for example we will likely convert to a Holley HP EFI with a Holley Cable Driven Throttle Body. (i have another project going right now on a 88 camaro that will be using Holley EFI and am thinking about standardizing on it, but will need to see how it works out)
Hopefully spring / summer returns to our neck of the woods soon so it can get back out on the road as he returns from college shortly
Clearly the LS3 / T56 combo is really wonderful... great performance, fuel economy, and reliability
We still have further updates in the future we will be doing. At some point for example we will likely convert to a Holley HP EFI with a Holley Cable Driven Throttle Body. (i have another project going right now on a 88 camaro that will be using Holley EFI and am thinking about standardizing on it, but will need to see how it works out)
Hopefully spring / summer returns to our neck of the woods soon so it can get back out on the road as he returns from college shortly
#50
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Re: 87 Formula LS3 Swap
yes, see post 11 in this thread for what we did (this is the vortec zz5 swap we did the year before putting the LS3 in)
https://www.thirdgen.org/forums/engi...50-vortec.html
https://www.thirdgen.org/forums/engi...50-vortec.html
Last edited by ShiftyCapone; 04-25-2018 at 08:12 PM.