Flywheel help
#1
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Just bought a top gun and have vibration/harmonics on port engine at higher rpms. I have checked with bravo drive off and still there, feels just like a bad gimble bearing or u joints.went through the top end-heads,springs,valves ect. new cam and lifters,swaped distributers and wires.and all the front pullys. The engine is a gen6 ( 100hrs since out of crate )and i suspect the previos owner may have used the wrong flywheel. casting # is 3973457n can anyone tell me if this is a compatable wheel for an externally balanced 502. I just dont want to go into this engine unless i have to. thanks
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Rudd,
the Gen V and VI use a different balance than the Gen IV, but the bolt pattern is the same and the old flywheel will bolt up. See if you can get your hands on a GM Performance catalog, they show alot of info. Not sure if it will idenify your wheel. But it may. You may be able to find a GM dealer that has one in stock that you could compare your flywheel with.
Hope this helps.
Dick
the Gen V and VI use a different balance than the Gen IV, but the bolt pattern is the same and the old flywheel will bolt up. See if you can get your hands on a GM Performance catalog, they show alot of info. Not sure if it will idenify your wheel. But it may. You may be able to find a GM dealer that has one in stock that you could compare your flywheel with.
Hope this helps.
Dick
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Here is the one you need casting #: Nodular iron with casting 809-14096805
buy good arp flywheel bolts too and use 271 Red Threadlocker from loc tite on the bolts and torque them to the right spec.
http://www.jegs.com/i/GM+Performance...96987/10002/-1
buy good arp flywheel bolts too and use 271 Red Threadlocker from loc tite on the bolts and torque them to the right spec.
http://www.jegs.com/i/GM+Performance...96987/10002/-1
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Thanks for the info, I suspected thats what the problem was. I sure wish I coud have caught it when the motor was out, but at least I dont have to rebuild.