OHC 6 Flywheel Questions
 

Using a '68 OHC 6 as the subject, I see rockauto still lists a new flywheel, LUK LFW131...:

LUK LFW131 Specifications:

Flywheel Diameter (IN) 10.969
Flywheel Inner Diameter (IN) 6.406
Number of Teeth 153


https://www.rockauto.com/en/moreinfo...t=5348&jsn=426

As a correct fit for the 4.1L engine, but it also is stated to fit a 5.7L LeMans V8, so, not sure how accurate the rockauto listing is.

It's been a while since I priced out a flywheel resurfacing, but it has to be around $50-$60 these days. However, the RA listing for the above LUK flywheel is $68 or so, which makes things much easier to buy and install a new flywheel...if they fit and function the same as an original GM flywheel.

Looking at OHC 6 flywheels online, as well as the pic Jeff H added in another topic, the LUK and factory flywheel are visibly quite different, with the LUK flywheel appearing much less "full" if that makes sense-- much less material around the outer perimeter/circumference, just inside the ring gear:

https://www.rockauto.com/info/797/LK..._Fro__ra_m.jpg

https://www.rockauto.com/info/797/LK..._Bac__ra_m.jpg


Honestly, it doesn't look "right", and using an original and having it resurfaced would be the safe route, but I'm just curious if anyone has used a new flywheel on an OHC 6 and if so, how did it work out?

Attached image of original flywheel mentioned above for comparison.

This looks like a better match, with 166 teeth (thanks Jeff H):

https://static.summitracing.com/glob...-155_at_xl.jpg

https://static.summitracing.com/glob...-155_at_xl.jpg

OEM flywheel for OHC-6 has a step in the flywheel surface
which if re machined need 2 surfaces resurfaced.
Short cuts are machine it flat.

Thanks. What was/were the reason(s) a stepped flywheel was used on the OHC 6? I don't think it was mentioned in the SAE paper Jeff scanned and uploaded, so now I'm curious.

Again, I'm not opposed to finding a good used flywheel and having it resurfaced, and very well may end up going that route. I would imagine a stepped flywheel is not very common at all, though, so at least it should be easy to spot.

If you find a flywheel that doesnt have the step chances are its been machined flat.

I agree, the 67 Manual flywheel had a step in it until I had it resurfaced a couple of months ago. I don't know why the step is there? I also know the original flywheel from my 1978 Sunbird with a 305 sbc also has a step in it. There must be a reason for it.