I have a manual flywheel dual bolt pattern that was balanced. It was pulled after about 3k miles of use from a 455 BBO. Bought it thinking I was converting over to a stick but not going that route. As you can see the teeth are good and it’s in good shape. Paid $200 for it. Was just hoping to get my money back. Would consider shipping on your dime but it is a hefty piece of metal.
Message me if interested.

 

Any idea what the other bolt pattern is for?

 

good question. Never bothered to ask. I just knew that I was going to eventually put it on my 69 Olds with a 455

 

It is probably designed to fit both the factory forged crank and the factory cast crank. What does the other surface look like?

 

^^^THIS. Fits both the 1964-67 motors and the 1968-up motors. Note that there are two locations for the balance weight also, one for each bolt pattern.

 

thanks for clarifying. Pics of opposite side to come in a bit.

 

Pic posted of reverse side. Sorry if its a bit dark, took pic at 6 AM with my phone

 

I would be interested in talking to you about acquiring that flywheel

 

any idea who made this flywheel?

 

yes and they sell them new for 224 plus shipping. Ive got the site address on my work computer if you need it

 

Any idea why this has only one pressure plate bolt pattern? All of the Olds flywheels I have, both early and late, have two pressure plate patterns.

 

Probably because they figure that if you have a performance application, you're going to use an 11" clutch.

 

But even the NOS late Olds flywheel I have has dual pressure plate bolt patterns.

 

Because the factory flywheel was also used behind 350 2bbl motors with 160 HP net and a 10.5" clutch. If you are spending the money on an aftermarket flywheel, chances are you have a higher performance motor and need the extra torque capacity of the 11" clutch.

And yeah, I realize that W31 motors came with the same 10.5" clutch as did L88 Corvettes. That was NOT the normal 10.5" clutch.