Flywheel/Pressure Plate Mounting Bolts

how good an idea is it to purchase standard grade 8 bolts and cut them to length instead of paying $7.50 per bolt (x12) at the dealer???? Or should I bite the bullet and fork over the cash to get the proper hardware?

best to use the correct bolts.i know it sucks for the price that we pay but the piece of mind is worth it,for me anyways.or else i drive myself crazy thinking to myself-is it ok? are they the EXACTLY the same each?etc...

Checker Auto Parts in my town has many different flywheel bolt availible and they don't cost that much.

I have 4 sitting in my garage that need shipping paid for and they are yours!!!

xjguy98 said:

how good an idea is it to purchase standard grade 8 bolts and cut them to length instead of paying $7.50 per bolt (x12) at the dealer???? Or should I bite the bullet and fork over the cash to get the proper hardware?

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Really bad idea, the heads are not the same.

If you were to check, you'd find that the grade 8 bolt doesn't have the same head style as the flywheel bolt (it's called a "place bolt,") but I think you can change the clutch retaining bolts without too much trouble - use SHCS for those (since they're nearly as strong as SAE Grade 8 as a rule, but are a little softer and can handle shear stress better.)

The "place bolt" usually has a small undercut on the head that allows for flexion of the bolt head, as well as a "spring load" on the retained part - which is something that shouldn't be done away with. Also, once you machine or grind down the SAE Grade 8, you lose the rust protection you get from the chrome or zinc chromate plating - a bad thing.

I know the threads are 1/2"-20 - can you tell me the underhead length on your bolts? I'll go through ARP for a set that can match up - if you're going to have to spend a few bucks, might as well do it right. I can work on the same thing for the clutch retaining bolts as well - I'm reasonably sure they're 3/8"-16 (please check,) but I don't know the lengths...

5-90

I beleive the Pontiac 1/2" flywheel bolts are what I used (ARP) on the Auto flywheel - The ones for the flywheel should also fit the manual trans flywheel.

I actually don't have any of the original hardware. I bought the transmission off a guy I know who swapped an AW4 in it's place and he got rid of the bolts. Not sure of the specs on the flywheel bolts but the pressure plate bolts are listed in the parts book as being 3/8-16x.84 (an odd size I know) Closest size to that is 3/8-16x7/8 but yeah, never thought about corrosion protection...might be an issue up here.