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**Jaxx_** · 10-05-2011, 04:42 PM

I was under the impression they were stretch bolts. If they're too long you could have them go too far and start tearing up the block. Honestly I'd rather just wait a week than risk having to take off the entire transmission again and possibly replace something even more expensive. I'm not sure on all the clearances, though.

**jlevie** · 10-06-2011, 05:14 AM

The flywheel bolts are not stretch bolts. Stretch bolts tightened by angle specs, but ordinary bolts have a torque spec. You can probably get away with using generic grade 8 fasteners, but it would be best to use the right bolts. If your dealer doesn't have them they can get them in a couple of days. or you can get them on-line and get next day shipping.

**nando** · 10-06-2011, 05:29 AM

the reason the stock FW bolts aren't threaded all the way to the bolt head is because this increases the shear strength of the bolt.

the bolt with the threads all the way to the head will be weaker in shear. guess why this isn't a good idea...

**ThePrussian** · 10-06-2011, 08:07 AM

Thanks guys.

No, I don't believe them to be stretch bolts either.

I do know that yes, fully threaded bolts are weaker in shear, but I couldn't imagine it would be make or break difference on a stock (ie not boosted) M20, plus the bolts that hold a dual mass flywheel on are fully threaded (maybe that fw is keyed to crank tho, I have no idea). I am an industrial fabricator by trade and rarely see anything let go in shear over that short a thickness, and we are not prone to using high grade hardware ($$) until deemed nec.

But no one has chimed in w "yeah I threw some grade fives in there and it held for years" so I guess I'll stick w the concensus lol ... thx guys. I mean really though, six dollars for a bolt? So ridiculous. They're prob 10 at my local stealership.

**nando** · 10-06-2011, 08:35 AM

sure you can't find them cheaper? I suppose time is an issue.

in any case - think about it like this. it's not fun to remove the transmission. it's even less fun if you had to remove it over 6 little bolts, even if they are expensive. and it would probably cause more damage if they did happen to fail.

**scottinAZ** · 10-06-2011, 08:59 AM

Email Blunt, bite the bullet and put the correct bolts in there. Its enough of a pain in the ass, that if you are wrong, and the McMaster ones dont work, you will be kicking yourself in the ass all the time you are re-doing the job. Stock flywheel bolts also have a thinner head than a standard bolt, that may be due to clearance issues inside the clutch. length should not be an issue...

**SkiFree** · 10-06-2011, 09:28 AM

Grade 8 bolts scare me on the flywheel, would probably run at least a 10.9 (OEM runs 12.9).

Nando is right --- They should be cheaper, and are. The BMW list price for the 12x28 flywheel bolts are currently $2.50 each. BMW part # 11 22 7 805 885 -- should be easily available from either dealership or someone with access to worldpac/IMC/SSF. (Such as myself, guten parts, blunt, etc, etc.) Shoot If you can't find someone I could have some on the way today but I'm west coast.

**ThePrussian** · 10-06-2011, 11:12 AM

Hey guys, thanks a lot. I did just catch the 12.9 thing!! Def agree there is no sense messin around w these.

You know who is the shit? GUTEN PARTS IS THE SHIT.

Weekend and money saved.

I have learned a valuable e30 lesson today!! Just awesome. I like dealing w good people.

(I'll skip the screw these guys and the other guys rant)

Thanks for the input fellas

**SkiFree** · 10-06-2011, 11:29 AM

I love stories with happy endings.

**Jaxx_** · 10-07-2011, 07:21 AM

Originally posted by SkiFree View Post

I love stories with happy endings.

I love happy endings too.

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Flywheel bolts??

Flywheel bolts??

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