Fasteners used to hold turbo to manifold

[gawdzilla]

Out of curiousity, what are you guys using to secure the turbo to the manifold? What thread/pitch, what kind of nut, stud/bolt?

I believe my Greddy came with M10x1.25/M10x1.5 studs (don't remember which side is the coarse/fine) and nuts (14mm wrench size).

I'm looking to weld a new T4 flange onto my manifold to beef it up a bit since the existing flange has been decked down significantly. I've seen all sorts of pre-tapped T4 flanges, ranging from M10x1.5, M10x1.25, 3/8"-16. I definitely want to keep the size of the nut a 14mm wrench size (or 9/16"). All the nuts sold on Mcmaster for any M10 stud/bolt are all 17mm wrench size, which is annoying. For some reason American "metric" refuses to have 14mm wrench size M10. The 3/8"-16 studs use 9/16" aka 14mm wrench size nuts, but the stud itself will be slightly thinner than an M10 (~9.5mm).

What fasteners do the full-race manifolds and 6boosts come with?

Last question: locking or non-locking nuts? I tend to stay away from the locking jam nuts because they usually need to be snapped off when you remove them. Copper or steel nuts? Lock washer or no?

[Shocker]

I ran into this same issue Gawd. My threads are what the stock exhaust manifold uses on the rb25. I think its m10x1.5. I might be wrong. (to lazy to look it up) But I was having an issue finding 14mm heads for the nuts. However I did get lucky and find a few at a local hardware store after some searching.

The manifold I bought from the AU came with jam nuts, with 14mm head. I used them. I HATED them until I found an easier way of installing the turbo. Remove the center section completely so its just the exhaust housing, bolt the housing down then add the center section. For me this is 100x easier.

I do use a lock washer, with steel nuts.

[Bluefire]

any hardware in a 10mm or 3/8" is fine and is pretty much standard. Thread pitch isn't much of a concern. For the stud you would want to use hardened/heat treated steel. Do not use stainless steel hardware because it will gall easily. As for the nuts, ideally you would want to use some copper locking nuts. I do not recommend steel locking nuts because they will usually pull the stud out if you try and loosen them off. If you can't find any copper locking nuts just use some regular hardened nuts. You'll just have to double check them every now and then as the studs will slowly stretch over time and the nuts will loosen. Also i would just use some flat washers, lock washers end up flattening out from the heat anyways...

[240z4u]

http://www.nord-lock.com/default.asp?url=2.16.37 for washers

[DrifterProdigy85]

I thought the manifold stuff was a Metric Fine thread which is 10x1.25mm.

[gawdzilla]

thanks for the replies. i'm gonna go with m10x1.25 probably...

I thought the manifold stuff was a Metric Fine thread which is 10x1.25mm.

depends on the manifold i think. are you talking OEM?

[Shocker]

I thought the manifold stuff was a Metric Fine thread which is 10x1.25mm.

Your correct, I just looked it up.