[TxGoat]

Pretty odd question here...I bought a 69 GTO with a chevy engine in it .....I'm replacing it with a 72 455. Will the flywheel from that Chevy bolt up to my 455, or do I need to go get another flywheel? The engine is with the builder, so I can't physically match it up right now. I'm reusing the BorgWarner T10, hoping to re-use the clutch and pressure plate, and still need to scrounge a bell housing as well.

Advice?? Thanks in advance.

[65gto69]

Pretty cut and dry:

You need a Pontiac flywheel/flexplate. The Pontiac flywheel/flexplate has 166 teeth and the chevy, I believe has 168. Since you are putting a Pontiac motor in, you are going to need a Pontiac starter. Pontiac starter gear will not mesh with chevy flywheel/flexplate.

Mark

[TxGoat]

Thanks. I certainly knew the starter couldn't be re-used and had a feeling the flywheel was a no-go.

Any thoughts on the clutch assembly?

[65gto69]

Well if you stick with the chevy bellhousing, you are going to need an adapter plate to make the bellhousing able to mount to the Pontiac block. Otherwise you will need a Pontiac bellhousing and clutch fork. I think everything else clutch related will work, those parts won't know from Pontiac or Chevy.

Mark

[old66tiger]

Isn't there any issue between the chevy and the pontiac flywheel balance as well?

[TxGoat]

Thanks. I think I can probably pick up a Pontiac bellhousing local. I'll give it a try for a couple of days and also check the ads here.

[65gto69]

Originally Posted by TxGoat

Thanks. I think I can probably pick up a Pontiac bellhousing local. I'll give it a try for a couple of days and also check the ads here.

Make sure you get a Pontiac clutch fork also, I don't think the chevy fork will fit.

Mark

[TxGoat]

Thanks. It actually has a hydraulic clutch in it. Kind of strange.

[gtofreek]

Originally Posted by old66tiger

Isn't there any issue between the chevy and the pontiac flywheel balance as well?

Pontiac flywheel/flexplates are counterweighted. Different from Chevies also. Also the bolt pattern is completely different, they won't even bolt up. Not even close.

Also, someone mentioned that the Pontiac starter won't even mesh with the Chevy flywheel because of the tooth difference. This is not true as both starters use the exact same starter drive. Since a Pontiac starter won't bolt to a Chevy and vice-versa, trying it is not even a possibility.

[goatman65]

If you change the starter 'snout' from the chev to pontiac the starter will work.the only difference is the opening for the starter pinion.

[gtofreek]

That is 100% correct!

[65gto69]

Sorry guys for my comment "that the starter won't mesh with the flywheel"

I did not know that from experience, I just figured that teeth count and diameter of the flywheel, would have an affect on the teeth count and spacing on the starter gear.

My bad.

Mark