HELP!! Flywheel Issues!
Thread Starter
Racer
Joined: Jan 2004
Posts: 463
Likes: 0
From: South Haven MI
HELP!! Flywheel Issues!
I am converting my 79 L48 from an automatic to a manual.
I bought a borg warner tranny, flywheel, belhousing, ect.. that came from a 78 L82. Went to install the flywheel and the center hole is
about 1/4" smaller in diameter than the flange on the crank. My 79's
engine came from a 72 Camaro. Is there an adapter plate? Or do I need to buy a new flywheel? Or will a shop widen the hole for me? What is the best solution here? Is there a crank for an automatic and a different crank for a manual?
I bought a borg warner tranny, flywheel, belhousing, ect.. that came from a 78 L82. Went to install the flywheel and the center hole is
about 1/4" smaller in diameter than the flange on the crank. My 79's
engine came from a 72 Camaro. Is there an adapter plate? Or do I need to buy a new flywheel? Or will a shop widen the hole for me? What is the best solution here? Is there a crank for an automatic and a different crank for a manual?
Last edited by jacobsed; Dec 30, 2004 at 10:41 PM.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by jacobsed
I am converting my 79 L48 from an automatic to a manual.
I bought a borg warner tranny, flywheel, belhousing, ect.. that came from a 78 L82. Went to install the flywheel and the center hole is
about 1/4" smaller in diameter than the flange on the crank. My 79's
engine came from a 72 Camaro. Is there an adapter plate? Or do I need to buy a new flywheel? Or will a shop widen the hole for me? What is the best solution here? Is there a crank for an automatic and a different crank for a manual?
I bought a borg warner tranny, flywheel, belhousing, ect.. that came from a 78 L82. Went to install the flywheel and the center hole is
about 1/4" smaller in diameter than the flange on the crank. My 79's
engine came from a 72 Camaro. Is there an adapter plate? Or do I need to buy a new flywheel? Or will a shop widen the hole for me? What is the best solution here? Is there a crank for an automatic and a different crank for a manual?
crankshafts are the same for auto/man.... i don't see why a machineshop couldn't widen the hole for you.....i'd would probalby try and find out why it isn't lining up and make sure there aren't any other differences such as offsets,bolt holes...etc... i would try and figure out what crank i had in there as a first priority....
Drifting
Joined: Aug 2004
Posts: 1,883
Likes: 124
From: Lubbock TX
Only ones I know of with smaller diameter center hole are the ones made for late model stuff. Different bolt pattern as well and aren't interchangable. You might want to check this out. I don't think they balance the same, either, so double check before you bolt it on. HTH
Thread Starter
Racer
Joined: Jan 2004
Posts: 463
Likes: 0
From: South Haven MI
I'm 99.99% certain it was built as a 350. What would be a definitive way to tell? What should the diameter of the hole in the flywheel be? Again, this crank works fine with the automatic tranny setup.
Burning Brakes
Joined: Apr 2004
Posts: 847
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From: Des Allemands LA
It doesn't matter if it was a 350, 327, 302(oh-yeah that was in '69 or '68 1/2 ), or any thing else if the motor is a small block Chev. the crank hub is not different between 72 and 79 whether it is a small/big block.
Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by ltlevil
It doesn't matter if it was a 350, 327, 302(oh-yeah that was in '69 or '68 1/2 ), or any thing else if the motor is a small block Chev. the crank hub is not different between 72 and 79 whether it is a small/big block.
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Burning Brakes
Joined: Apr 2004
Posts: 847
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From: Des Allemands LA
Something else, I'm not sure if you explained this correctly or not or if I understood this correctly or not, but are you talking about the flywheel "hole" or where the trans input shaft goes into the crank?
Burning Brakes
Joined: Jul 2000
Posts: 1,045
Likes: 3
When you look at the back of the block does it have a one or two piece rear seal. You might have a newer style block that use a differant type crank. One piece rear seals you can see the seal when looking at the back of the block. Just a idea....
Team Owner
Joined: Jun 2001
Posts: 23,375
Likes: 1,067
From: Virginia USA
Originally Posted by toyvet1
When you look at the back of the block does it have a one or two piece rear seal. You might have a newer style block that use a differant type crank. One piece rear seals you can see the seal when looking at the back of the block. Just a idea....
Race Director
Joined: Jun 2000
Posts: 10,046
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From: FL
When GM made the motors, they sometimes ID'ed the ones for automatics earlier. This allowed them to to skip some of the machining on the rear of the crank (saved $$$).
Make sure that you have a machined hole for the pilot bearing as well.
Make sure that you have a machined hole for the pilot bearing as well.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,502
From: Little Rock AR
It is a Ford engine and a Chrysler flywheel. Get a bigger hammer and make it fit 
Seriously, you can ID the engine by looking at the back of the crank flange. The 283 has a full round flange, the 302 has the single notch on a round flange, the 327 small journal has a round flange with 2 notches, the 327 large journal has a round flange with 2 notches and a fan shaped counterweight, the 350 looks the same as the large journal 327 but the counterweight is full width across the top of the flange. Manual or automatic are the same piece but the manual needs to have a pilot bushing installed in the back of the crank.
I would get a new flywheel. They do not cost that much and besides, who knows what you realy got from the other guy.
-Mark.
Seriously, you can ID the engine by looking at the back of the crank flange. The 283 has a full round flange, the 302 has the single notch on a round flange, the 327 small journal has a round flange with 2 notches, the 327 large journal has a round flange with 2 notches and a fan shaped counterweight, the 350 looks the same as the large journal 327 but the counterweight is full width across the top of the flange. Manual or automatic are the same piece but the manual needs to have a pilot bushing installed in the back of the crank.
I would get a new flywheel. They do not cost that much and besides, who knows what you realy got from the other guy.
-Mark.
Thread Starter
Racer
Joined: Jan 2004
Posts: 463
Likes: 0
From: South Haven MI
OK, thanks for the input.
I just got a used flywheel out of the salvage yard and had it machined down. $20 for the flywheel and $20 for the machining. I have a 350 with a 2 piece rear main seal. The flywheel that I initially had was for a newer engine because it had a smaller center hole and the bolt holes were offset. I'm off to the garage to finish mounting this bad boy up.
I just got a used flywheel out of the salvage yard and had it machined down. $20 for the flywheel and $20 for the machining. I have a 350 with a 2 piece rear main seal. The flywheel that I initially had was for a newer engine because it had a smaller center hole and the bolt holes were offset. I'm off to the garage to finish mounting this bad boy up.
Team Owner
Joined: Sep 2003
Posts: 88,393
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From: eville in
Originally Posted by SteveG75
When GM made the motors, they sometimes ID'ed the ones for automatics earlier. This allowed them to to skip some of the machining on the rear of the crank (saved $$$).
Make sure that you have a machined hole for the pilot bearing as well.
Make sure that you have a machined hole for the pilot bearing as well.
