Flywheel for 1965 BB

[Joel T.]

Hi,

I am still working on the power train for my '65 BB. Can someone provide the correct specification for the flywheel? My recollection is that it was either 10.5" or 11" with 153/155 teeth...

Thanks as always!

Joel

[Mark S. Lovejoy]

Re: Flywheel for 1965 BB

This flywheel, is a 12-3/4" flywheel designed for use with a 10-1/2" clutch. It is still available today under GM PART #14085720.

[Jack H.]

Re: Flywheel for 1965 BB

The small, high mass, 10.5" flywheel was used on both 396 and L88...

[Joel T.]

Re: Flywheel for 1965 BB

Hi Mark/Jack,

I kept the flywheel which was on the car when I got it (in spite of the machine shop folks telling me to trash it). It is a 14085721N (as opposed to 14085720). It measures 12 3/4" across with a clutch area of 10.5"

Is this a viable replacement part??

Thanks,

Joel

[John H.]

Re: Flywheel for 1965 BB

Joel -

Yes. 721 is the casting number, 720 is the PART number.

[Joe L.]

Re: Flywheel for 1965 BB

Joel------

You've got exactly the right one. The 14085721 is the CASTING NUMBER for the GM #14085720 flywheel. The 14085720 is the correct replacement part number for your L-78 application. Other than the casting number and some other rather insignificant details, the 14085720 flywheel is the same as the original flywheel, GM #3866735, casting #3856579.

Both the 14085721 and the 3866735 are lightweight (about 15 lbs), 12-3/4", 153 tooth ring gear flywheel designed for use with a 10-1/2" clutch. 63-68 Corvette small blocks used a similarly configured flywheel, but it was of "standard weight".

[Joel T.]

Re: Flywheel for 1965 BB

Gang..

Well, I'll be dipped! This flywheel is about the ONLY thing which was correct on that car!

Guys, thanks again!!

Joel

[Joe L.]

Re: Flywheel for 1965 BB

Joel-----

Well, it's not actually "correct" in the "originality" context of the term. However, it is absolutely the correct replacement and it will function absolutely perfectly. No one will know the difference, either, until judges with "x-ray vision" are found.

If it were me and in the case of a flywheel, if I had the choice of a USED original flywheel or a NEW GM #14085720, I'd use the latter EVERY TIME.