m50 exhaust studs help!

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makman
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Post Thu Nov 01, 2012 12:38 pm

Can enyone tell me the thread pattern on an M50 exhaust stud?

ino there m7 but im unsure of the pitch and im away from the car so removing ones not an option!
Thanks
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redcar
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Post Thu Nov 01, 2012 1:21 pm

Is it number 11 on this diagram?

http://bmwfans.info/parts/catalog/E36/C ... nder_head/

I think they're m7x1.0
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makman
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Post Thu Nov 01, 2012 1:34 pm

ledgend! thanks redcar
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redcar
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Post Thu Nov 01, 2012 1:35 pm

no problem :)

you buying new ones or tap/die the old ones?
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makman
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Post Thu Nov 01, 2012 1:36 pm

bolting the manifold up! bmw want a fortune for genuine studs and nuts :/
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redcar
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Post Thu Nov 01, 2012 1:38 pm

makman wrote:bolting the manifold up! bmw want a fortune for genuine studs and nuts :/
So you're going to use 24 bolts to hold the manifold on? No Studs and Nuts?
BATTS91
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Post Thu Nov 01, 2012 1:42 pm

I went to bmw colchester , studs were 0.39p Each and nuts 0.41p

In total with full set of studs nuts and gaskets cost me £45 i have part numbers if you wish
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makman
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Post Thu Nov 01, 2012 1:51 pm

the BMW dealership near me wants to charge £1.12 per stud and £1.30 per bolt.

ive got about 8 studs so it will do to hang the gaskets and manifolds in place whilst I bolt it up. ino the owner of a local bolt company whos gonna give me them for free so in essence, yeah, im bolting it on. why not ey? aha
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BATTS91
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Post Thu Nov 01, 2012 2:06 pm

Because theres a reason car manufactures dont do it ;)
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makman
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Post Thu Nov 01, 2012 2:08 pm

re writing the BMW rule book ;) haha
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redcar
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Post Thu Nov 01, 2012 2:17 pm

Don't bolt them on dude! You will probably end up stripping the threads in the head. Similar reason why on turbo engines they replace the existing head bolts with a stud and nut method. It's much stronger.

Get studs and nuts :)
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makman
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Post Thu Nov 01, 2012 2:18 pm

surely if the bolt goes well into the head (same as the stud) then it would be orite? il see if hes got some threaded bar which I can cut down and make into studs :)

refuse to pay the money BMW want for them lol
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redcar
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Post Thu Nov 01, 2012 2:21 pm

what happened to the old ones? Maybe someone scrapping an m50 engine will have some spare. You will need new copper plated lock nuts regardless.

The bolt will torque into the threads in the head only. A stud and nut works differently and is much safer.
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makman
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Post Thu Nov 01, 2012 2:48 pm

ah fair enough :) and when I did the engine conversion i removed all the bolts from my m50 and m20 and layed them on the side in the workshop, some gimp dropped them all and then when I came to rebuild it I had a miss match of different sized studs etc, ive been running it with about 18 in for a while and the other ones are rusted up to the nines apart from the 8 im gonna use. Just wanted to refresh them all and get all 24 in haha. Ive just had my stainless manifolds tig welded up cos they were cracked and im rebuilding all the exhaust system so I want everything to be minter.

mite ring GSF or euro car parts and see if they can sort me a good deal if my mate doesnt have none.
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redcar
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Post Thu Nov 01, 2012 2:55 pm

makman wrote:ah fair enough :) and when I did the engine conversion i removed all the bolts from my m50 and m20 and layed them on the side in the workshop, some gimp dropped them all and then when I came to rebuild it I had a miss match of different sized studs etc, ive been running it with about 18 in for a while and the other ones are rusted up to the nines apart from the 8 im gonna use. Just wanted to refresh them all and get all 24 in haha. Ive just had my stainless manifolds tig welded up cos they were cracked and im rebuilding all the exhaust system so I want everything to be minter.

mite ring GSF or euro car parts and see if they can sort me a good deal if my mate doesnt have none.
If you're making it mint the first place i'd start is new nuts and new studs. If new studs are a problem then cleaned up, re died second hand ones should do. Remember to copper grease them as well so it's easy the next time they need to come off.
Just don't use bolts!
BATTS91
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Post Thu Nov 01, 2012 9:09 pm

Exactly what my next response was going to be , the pressure will rip the thread out of the head . Do it right do it once ;) .
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Post Thu Nov 01, 2012 9:16 pm

My local nut and bolt shop does studs etc and can usually get odd ball sizes.

At work, we keep wurth stuff in, they do clips, bolts etc for all different manufacturers. Maybe worth digging.

As above stick with studs and nuts its a lot stronger, hence why people convert head bolts to studs as its pulling on 2 sets of threads rather than one.
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Jimbob
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Post Thu Nov 01, 2012 9:20 pm

It's £4.83 for 24 studs from Cotswold, give them a try!
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Post Thu Nov 01, 2012 9:38 pm

Thats cheap jimbob ! , give them a message makman