Manifold Downpipe Nuts

[nightroamer]

What size/thread are they, i have tried loads out of my box of bits but none seem to have the right thread, is it maybe imperial??

[abelai]

They are m10 1.25 i think and they are not normal nuts but you can get them from BMW for about £0.25 each.

[12345kevin]

Need to be copper or copper plated nuts if you want to get them undone again I think

[nightroamer]

would a slightly loose down pipe, ie on 3 not 4 nuts cause the car to idle roughly, like a missfire and stall?

[Nelly]

It can do if it's leaking gasses, the mm size of the originals are 14mm iirc.

[HairyScreech]

as above, i replaced mine with 15mm flange bolts.

[nightroamer]

sorry for delayed reply, yea bmw have issued me with a 15mm saying its standard, so will try it in a bit