Turbo Studs?

[rodo]

The saga continues... turbo, manifold, and elbow are back from machine shop, nicely leveled, ready for installation. Now I just need to find new studs for the turbo/manifold connection. The problem is that they are a M8 1.5pitch on the manifold end and 1.25 for the turbo side. Anyone find something that will work for these? Anywhere?

[18Fiatsandcounting]

Good question. I'm sure someone makes them, but I didn't find anything with a quick search. What I would do is call companies like McMaster-Carr, Grainger, Bel-metric, Boltdepot, Fastenal, etc. I'm sure one of these companies would know.

-Bryan

[rodo]

Thanks, Bryan, but have been on all those sites and nada. Even wrote to them, and a few others. Trouble is the weird 1.5 pitch and 1.25 on the same stud. Is there anything about the turbos that is not weird?

[rodo]

And...I'm on crack. Same at both ends. Or, at least, mine are. Turns out the end I thought was a different pitch just was utterly buggered up. Going to that high speciality classic import car parts place: ACE.

[18Fiatsandcounting]

Awesome, Rodo, Ace is the place! But, I have run across studs that really did have different threads on either end, but it wasn't on a Fiat. American car of some older vintage, as I recall.

-Bryan

[rodo]

And I am sure that there are some bolts on the FIAT, I think it was for the A arms, that have 1.5 pitch. (That's when I first learned about bolt pitch...the hard way.)

[Nut124]

Even if you thought the original had a different pitch at each end, it would not matter. The stud could just as well be substituted with one that has the same pitch. Works the same. Not like the stud threads into the turbo. It's a nut of your choosing.

The only thing that would change is the max nut torque, slightly.

[rodo]

Nut124,

Thanks for making me feel even more stupid!

Of course: I could have flipped the studs and used a different nut! Sheesh,funny how the mind works. Or in my case, doesn't.

But as it turns out, two of the studs go all the way through the turbo manifold, there is no stopping point. No wonder they come loose! I'm working on a plan to use a longer stud with a nut at the manifold end exit to keep it from pulling loose. Got to do some measuring as things are tight there. If it works, I'll post pics.

[rodo]

I substituted 40mm studs for the factory 30mm and they are just right, just long enough to take the self-locking nuts at both ends. (Top image has both longer studs in position. The "front" studs actually bottom out in the manifold so are not the same concern. Bottom image has but the right longer stud fitted. Notice the nifty AR brass high temp locking nut.)

This can only be better than the weird original studs. If this doesn't lock things together...