kendogg

iTrader: (2)

I need 40mm long flywheel bolts, pretty sure all LS are M11x1.5? Does anybody know where I could find these without having to have ARP custom make them? Thanks.

BALLSS

whatever donor car/motor type you are talking about, the dealership parts counter should have the correct FW bolt if ARP does not make one (I would think they do)

SLP IROC-Z

iTrader: (14)

Why do you need longer flywheel bolts?

stevieturbo

I think someone said the flywheels on the front wheel drive variants had a taller flywheel or something ? Maybe they might use longer bolts.

Aside from that.....why do you need such long bolts ?

M11x1.5 wouldnt be particularly common, but I'm sure somewhere sells bolts.

Looks like 234-2801 is longer than typical LS1, but still not 40mm, although that depends where you're measuring it.

Or you could buy these and cut them down to whatever length you need

https://www.ebay.co.uk/itm/BMW-Torx-...UAAOSwfMtZflgF

kendogg

iTrader: (2)

Sure, I'll go right to the parts counter and get flywheel bolts for the PMC flywheel I'm putting behind an LS to run a BMW gearbox..... I was very specific about what I asked for for a reason.


Running a PMC adapter kit to run a BMW 6 speed behind an LS. Flywheel is thicker, and stacks an automatic flexplate behind it to run the starter. PMC doesn't suppy bolts, states they are very hard to come by in Poland, but gave me dimensions - M11x1.5 x 40mm length.

This kit, but we're sourcing our own clutch (Sachs Sport HD pressure plate and a custom 'dual friction' disc): http://www.pmcmotorsport.com/gegearb...w-m50-m57.html

stevieturbo

Those BMW bolts would be your best easy option then, and listed as 12.9 are proper high tensile. Even standard GM flywheel bolts are a lower grade
Any BMW dealer should be able to get them for you

stevieturbo

A little googling, looks like they are main cap bolts from some of their engines

http://bmwfans.info/parts-catalog/E3...lock#1745188_2

kendogg

iTrader: (2)

S54 head bolts are also M11x1.5, but they're a tall E-torx head. I'm not sure I like the idea of cutting them down, but....

stevieturbo

Most head bolts will have a long unthreaded portion though, so may not be suitable for what you want.

kendogg

iTrader: (2)

Some. Most of the BMW ones are fully threaded though.

BALLSS

…..well OP, responded to your initial post that was vague about what car the "LS" was going in let alone what tranny attached. Assumed it was a LS/T56 swap into something vs a LS into BMW using the BMW trans....which apparently requires a flexplate between FW & crank so starter will work

Your later post then was more detailed on what your "unique" situation is

Sooo, now with more info....you can likely source the desired bolt size and thread pitch you want but will likely have to cut the heads down as FW bolts typically have short heads to clear the clutch assembly

Fastenal may be a source worth checking for the bolt....

kendogg

iTrader: (2)

Yes, it's unique, but my OP was very, very specific as to what I'm looking for - there was no more information necessary. Fastenal doesn't stock any M11 bolts, I've tried. ARP doesn't have anything long enough either. I am going to inquire about the cost to make a custom set though before breaking down and cutting main bolts to fit.

pdxmotorhead

Go to your nearest Airport with a flight service center that services aircraft engines...
Aircraft hardware comes in short head and long head bolts with safety wire holes pre-drilled.
Grade 12 AP.. If you break those your a manly man.. LOL

BALLSS

I suspect custom made bolts will cost big $ to be made if you can or take a bigger donor bolt and have it machined down to the M11 and head cut down or the main bolt cut down you mention

Sounds like you have already checked the usual suspects (ARP, Fastenal, McMaster, Grangers)

I assume you will also need to sort out pilot bearing for the LSx/BMW trans...and the bellhousing mid plate if needed to clear the extra thickness with the Flexplate between crank & FW...and then is input shaft of tranny now long enough to reach pilot bearing with enough contact

Have seen LSx/T56 transplants in Bmers...not with the BMW trans though

Good luck with the build

kendogg

iTrader: (2)

Pilot bearing extension is built into the custom flywheel. I think the G420 is a great alternative to the overly expensive, notchy T56. Better gearing, MUCH stronger in stock form, lighter weight and linkage based, so no issues on where the trans end\s up. And the I6 ones are ~$1000, and the V8 ones are ~$400 (same trans, different bellhousing. Trying to get somebody to build an adapter plate for the V8 box instead, but thats for another project).

stevieturbo

As he is not using an LS flywheel or clutch....I'd guess it wouldnt be a big deal if the bolt heads are a little larger than a typical LS.

kendogg

iTrader: (2)

ARP wants $800 machine setup fee. I totally get it, but can't do it for 6 bolts lol. I guess a cut down set of main bolts it is

BALLSS

Well custom builds=custom fabrication...been there.

If this custom FW has the bolt holes recessed some maybe standard bolt head bolts would clear clutch...but machining some off bolt heads should not be a problem if required

stevieturbo

I'm sure there are plenty of places who could make bolts...but for just 6 it is a bit daft when there seems to be other cheap solutions

Or at a push....running an M12x1.5 tap might knock the hole out to that size. It'd probably go easy on a factory cast crank...maybe not an aftermarket steel crank. Then bolts might be more common ( and drill flywheel to suit )