1971 LT1 Flywheel Questions

[Todd Stevenson]

Greetins All,
I need some help with the flywheel on my 1971 LT1. Can someone tell me if my flywheel is a 168 tooth or a 153 tooth? Also, I'd like to know if the Findanza aluminum flywheel is a worthy up grade? Any info would be greatly appreciated.
Thank you,
Todd Member # 40534

[Duke W.]

Re: 1971 LT1 Flywheel Questions

What benefits do you expect to receive from an aftermarket aluminum flywheel?

Duke

[Joe L.]

Re: 1971 LT1 Flywheel Questions

Todd-----

Unless you have one of the 8 1971 ZR-1s made, your flywheel should be a 14", 168 tooth unit. You can use the bellhousing as a secondary and easy check. It should be a GM #3899621 and that number will appear prominently displayed on the side of the casting.

As far as an aluminum flywheel goes, I wouldn't touch one with a 10 foot pole. If someone GAVE one to me, I wouldn't put it on my car.

[Todd Stevenson]

Re: 1971 LT1 Flywheel Questions

Joe,
Thanks very much for the info. I did not know that ZR1's had a different flywheel. I'm curious...what was different about the ZR1 flywheel? I thought the only differences were the obvious things like J56 brakes, radio delete and other items listed in all the reference books. Are there other "subtle" differences in the ZR1's?
Thanks again,
Todd

[Joe L.]

Re: 1971 LT1 Flywheel Questions

Todd----

I think that most of the differences are listed in the generally available books. The clutch and flywheel is an exception. The clutch used was a special 10-1/2" unit. It was basically the same as the L-88 clutch used previously, although 71-72 LTs used a 26 spline disc rather than the 10 spline used for all L-88s and 1970 ZR-1s. The flywheel was a special lightweight 12-3/4". Once again, the same as used for L-88.

The bellhousing used was the GM #3858403. While this bellhousing was also used on many 1964-68 Corvettes, the only use of it on a Corvette after 1968 was the 1969 L-88/ZL-1 and the 70-72 ZR-1 application.