Garrett GT20 Project

[306Puggy]

Just looking at the manifold and adapter plate now, I think the only option for the turbo flange to adapter plate bolts is to tap the holes for the turbo flange in the adapter plate and then drill holes (and possibly tap) in the manifold to give the rest of the thread of the bolts room to go through. All together that would give me about 20mm of threaded hole for the turbo flange bolts assuming I leave 1mm to stop going through into the actual manifold area. And this turbo does feel hefty and the bolts are not very big

Ideally I should get a thicker plate and get some countersink bolts but I don't want to waste this adapter plate that I have got ready. The main question is then, would 20mm of thread be enough to hold the turbo on with 3 bolts?

Edit: Just found this thread:
http://306oc.co.uk/forum/thread-2611.htm...er%2Bplate

Ruan says that 6mm plate should be okay to countersink bolts in. So now it is a question of which is better? Trying to countersink the bolts or drilling and threading?

Edit: Just realised I won't be able to countersink the bolts and then do them up! If the bolt head is going to be against the manifold mating surface, how am I gonna get an allen key/torx bit into the bolt head!? I won't be able to, that's how! Back to the original plan then. Actually I could get them welded and then they would be studs. Yeah, that sounds like the best solution.