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Old 04-10-2010 | 08:05 AM
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From: king george, va
Default 502 flywheel question

Hi, I'm slowly trying to finish up a motor to put in my boat hopefully in a month. Here's my question, I'm going from a gen IV 454 to a gen VI 502. Can I just go to my local gm dealer and get a flywheel for a 502 and it should work or do I need a different one. If so does anyone know the part #. Thanks
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Old 04-10-2010 | 08:32 AM
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Originally Posted by chuckyarus
Hi, I'm slowly trying to finish up a motor to put in my boat hopefully in a month. Here's my question, I'm going from a gen IV 454 to a gen VI 502. Can I just go to my local gm dealer and get a flywheel for a 502 and it should work or do I need a different one. If so does anyone know the part #. Thanks
Call 1800runsnew, just bought one from them its a real gm for a forged 502 crank, think it was 240.00 plus 15 to ship it...they stock them. or check out their web site
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Old 04-10-2010 | 10:20 AM
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Do you have the flywheel from the 454? It should be the same thing...maybe the numbers on it are different, but it IS the same. Your old MK-4 motor was an external balanced motor as is your Gen VI 502. The crank...forged or cast doesnt make squat for difference. The ONLY differences in flywheels is EXTERNAL balance, INTERNAL balanced or the number of teeth on the flywheel. You will need 168 teeth on whatever flywheel that you get, but you cant mix the flywheels...IE...external balance harmonic balancer and an internal balanced flywheel. I have external balanced flywheels that came off 454's and 502's, and HARK...they weigh the same. If you want one for alot less than what you will pay at the GM dealer...holler if you want one of these
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Old 04-10-2010 | 11:12 AM
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You need this one
http://www.jegs.com/i/GM+Performance...96987/10002/-1


do not run the old flyweel for the cast cank
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Old 04-10-2010 | 07:27 PM
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Originally Posted by PSlonaker
Do you have the flywheel from the 454?
P,
You really should not make these comments without knowing for sure.

The MKIV engines use a different flywheel than the MK5 and newer. The balance weight is different because the MK5's have a one pc rear main seal and the crankshaft does not have the counterbalance on the back flange. Also, as was already mentioned, the cast crank and the steel cranks use a different flywheel, also due to balancing differences.

You have to get the correct flywheel for the engine.

Bill Koustenis
Advanced Automotive Machine
Waldorf Md
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Old 04-10-2010 | 07:45 PM
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Bill K and Rockfish are correct.

Both have helped me and KNOW what they are talking about.

BOTH are respected in the business so listen in learn.

I also hate people giving advise that they have no idea what they are talking about.

I would order the ones on ROCKFISH link.

Like BALLON I paid $200 X 2 for new ones from 1800.

Last edited by 1BIGJIM; 04-10-2010 at 07:48 PM.
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Old 04-10-2010 | 08:21 PM
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Originally Posted by BillK
P,
You really should not make these comments without knowing for sure.

The MKIV engines use a different flywheel than the MK5 and newer. The balance weight is different because the MK5's have a one pc rear main seal and the crankshaft does not have the counterbalance on the back flange. Also, as was already mentioned, the cast crank and the steel cranks use a different flywheel, also due to balancing differences.

You have to get the correct flywheel for the engine.

Bill Koustenis
Advanced Automotive Machine
Waldorf Md
We use the external balanced 168 tooth flywheels all the time on stock 454 and 502 motors and we have NO ISSUES at all. All of our custom built motors andre internal balanced so things are different there, but you guys do whatever you want. We have no complaints on our motors and we have no issues, so I will continue to do as we have all along.
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Old 04-10-2010 | 08:24 PM
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Originally Posted by BillK
P,
You really should not make these comments without knowing for sure.

Careful now...

The MKIV engines use a different flywheel than the MK5 and newer. The balance weight is different because the MK5's have a one pc rear main seal and the crankshaft does not have the counterbalance on the back flange.

That is true.

Also, as was already mentioned, the cast crank and the steel cranks use a different flywheel, also due to balancing differences.

That is not true.



There's two 168 tooth flywheels for externally balanced big blocks:

3993827 - MkIV

14096987 - GenV and GenVI

Within the same generation engine, it makes no difference if it's a 454 or 502, cast crank or forged.

That's the truth.
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Old 04-10-2010 | 08:26 PM
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Originally Posted by cubicinches
There's two 168 tooth flywheels for externally balanced big blocks:

3993827 - MkIV

14096987 - GenV and GenVI

Within the same generation engine, it makes no difference if it's a 454 or 502, cast crank or forged.

That's the truth.

THANK YOU
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Old 02-05-2023 | 02:09 PM
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Originally Posted by pslonaker
THANK YOU
are you guys sure about this? So I can use the flywheel that came off my cast gen 6 454 and put it on my 502?
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