1984 Corvette "LS1" Engine Swap/Build
#43
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There's some kind of spacer-.4" ? You'll need behind the flywheel. Something to do with the block depth at the rear. Lay a straightedge across where the crank comes out; compare motors. I believe you can get the spacer from GM. Nice swap !
#45
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Basically with the Gen III engine the crank snout is .400" closer to the front of the block than a standard Gen I / II SBC engine. Add the different bolt pattern and that the engine is internally balanced and a problem arises in swaps. Unless someone makes a flywheel with the correct offset, the transmission input shaft will have to be modified / changed if a T-56 flywheel were used on the stock bell housing he already has. I know there are adapter options but I don't know what transmissions they work on. I've always gone the auto route but want to go manual next time. I'll dig through my notes and post what I find.
#46
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I don't believe that you'll nee a spacer or bellhousing if you use the LS-truck/CTS-V pilot bearing, which mounts in the rear-most crank flange instead of the recessed position used by the Camaro/Corvette.
See if you can borrow a 168t LS flywheel for a test fit with your bellhousing.
I'd try to find a Camaro or C5 Corvette unit as has no rear offset and won't add to any clearance issues inherent in the larger diameter.
Look at the clearance around the starter gear, if it clears ok (some relief grinding is acceptable, just don't get carried away), you should be able to get a good machinist with a rotary-indexing table to redrill it for the smaller C4 pressure plate. I would also get it spun up on a balancing machine to make sure all is kosher prior to putting it in the car.
Also, you'll also need to test fit your LS starter with the C4 bellhousing/LS flywheel to see if any relief is needed around the starter's nose.
Does anyone make a 153t LS flywheel, or starter?
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#47
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The 5.3L and the 5.7L motors use a different crank bolt pattern for some reason. I will NOT be able to get a 5.7 LS1/LT1 flywheel to bolt up to my 5.3L unless I can re-drill the crank holes on the flywheel.
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Although the C4 bellhousing is "space-impaired", it's more in the clutch area.
I don't believe that you'll nee a spacer or bellhousing if you use the LS-truck/CTS-V pilot bearing, which mounts in the rear-most crank flange instead of the recessed position used by the Camaro/Corvette.
See if you can borrow a 168t LS flywheel for a test fit with your bellhousing.
I'd try to find a Camaro or C5 Corvette unit as has no rear offset and won't add to any clearance issues inherent in the larger diameter.
Look at the clearance around the starter gear, if it clears ok (some relief grinding is acceptable, just don't get carried away), you should be able to get a good machinist with a rotary-indexing table to redrill it for the smaller C4 pressure plate. I would also get it spun up on a balancing machine to make sure all is kosher prior to putting it in the car.
Also, you'll also need to test fit your LS starter with the C4 bellhousing/LS flywheel to see if any relief is needed around the starter's nose.
Does anyone make a 153t LS flywheel, or starter?![Secret2](https://ls1tech.com/forums/images/smilies/LS1Tech/secret.gif)
I don't believe that you'll nee a spacer or bellhousing if you use the LS-truck/CTS-V pilot bearing, which mounts in the rear-most crank flange instead of the recessed position used by the Camaro/Corvette.
See if you can borrow a 168t LS flywheel for a test fit with your bellhousing.
I'd try to find a Camaro or C5 Corvette unit as has no rear offset and won't add to any clearance issues inherent in the larger diameter.
Look at the clearance around the starter gear, if it clears ok (some relief grinding is acceptable, just don't get carried away), you should be able to get a good machinist with a rotary-indexing table to redrill it for the smaller C4 pressure plate. I would also get it spun up on a balancing machine to make sure all is kosher prior to putting it in the car.
Also, you'll also need to test fit your LS starter with the C4 bellhousing/LS flywheel to see if any relief is needed around the starter's nose.
Does anyone make a 153t LS flywheel, or starter?
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#51
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Great project. This is going to be my project this summer only My C4 is a 85 and i will be replacing the TPI 350 with a 6.0L LS. Car is a auto with the 700r4 but there will be a 4L60E that has all the goodies within. (brother in law builds trannys at a shop for a living and I use to be a builder).
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Yeah i decided against that. I found out that a 621 bellhousing will work for my application with a hydraulic throw out bearing. I am currently looking for a cheap 621 or similar bellhousing.
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Thanks Jay Rod...
Well today I finally just bought a bell housing that I hope will work with my tranny and my clutch setup. I also received in the mail motor mount adapter plates from Speed Hound Parts. I will post some pics of everything sometime this week :thumbs:
Well today I finally just bought a bell housing that I hope will work with my tranny and my clutch setup. I also received in the mail motor mount adapter plates from Speed Hound Parts. I will post some pics of everything sometime this week :thumbs: