exhaust stud bolt size/threadpitch?

[Pantless Spency]

i need new exhaust port studs and i was wondering what size and thread pitch ETA head ones are, i'd rather save some money getting them at a hardware store than paying like 30 online.


thanks in advanced fellas

[jlevie]

The studs are M10x40 for the header to down pipe flanges and M8x40 for studs in the head. Don't use generic nuts. Get the copper plated ones from your dealer.

[M44schnell]

Here is a link to what i did

http://www.autohausaz.com/search/product.aspx?sid=zczjjn220ixowravugybh355&makeid=800003@BMW&modelid=1011654@325E&year=1986&cid=21@Exhaust%20System&gid=5879@Exhaust%20System%20Nuts,%20Bolts,%20Screws,%20Washers

[MR 325]

The stuff is really cheap, just get OEM.

[TheTacoMan]

I think it was like $1 a stud on pelican parts.

[jeffnhiscars]

The studs are M10x40 for the header to down pipe flanges and M8x40 for studs in the head. Don't use generic nuts. Get the copper plated ones from your dealer.

I was pulling studs off my old head today and the intake side were plated and the exhaust were black. It does make more sense to have the plated one on the exhaust side along with the copper nuts. Not sure why BMW did that.

[jlevie]

The IPB calls both zinc plated and and plain studs. I've seen heads that have never been touched that have plated and plain studs on the intake side. Any plating on the exhaust studs would probably have been lost in the last 20 years.

Cliff Notes Version: Plain or plated studs can be used on either side of the head. If makes no difference. But it is important to use copper plated nuts on the exhaust side.

[jeffnhiscars]

Cliff Notes Version: Plain or plated studs can be used on either side of the head. If makes no difference. But it is important to use copper plated nuts on the exhaust side.

Thats always been my theory.