fejjj

I have an 89 951 with 74k miles.

Head has been off of car 1 other time.

I am putting on a rebuilt o ringed, ported/polished head. Head is flat.

What are your thoughts on reusing the factory studs with new nuts?

Planning on running 17lbs boost on E85.

Techno Duck

I have reused them a few times; replace the nuts and washers though.

fejjj

Thanks Jon!

V2Rocket

+yes

fejjj

Thank you Spencer.

kevin12973

Pulling the studs is a real pain in the a$$. Don't do it unless it's absolutely necessary. I just did mine but I used heat, lots of heat!

V2Rocket

I wouldn't bother replacing the studs unless you were having the block machined (bored out or other procedure).

odonnell

Spencer,

Would you recommend replacing them for a supercharger build? < 10 psi

V2Rocket

Since the 944 studs are the same as the 951 studs at 11-12psi stock...they should be fine

fejjj

The machine shop pressure tested my existing head and said there were no cracks but that there was evidence of the head lifting.

This makes sense as I had combustion gasses in my coolant tank but no mixing in the oil.

Also the HG when removed was not blown.

I don't know if the mechanic who replaced the HG last time used the new torque specs and I am fairly confident he used the old specs.

Would you guys still use the existing studs?

V2Rocket

I have only used the "old" specs without issue but I guess they were revised for a reason.

New studs aren't that expensive (like $5/ea?) if you do want to replace.
If it were my engine I'd just have the head rebuilt and skimmed flat and bolt it back on.

Arominus

What are the new specs? i just had the head off, and now i'd like to know that i did it right.

V2Rocket

instead of 3 torque specs, there is one torque spec and 2 "torque angles"

Arominus

Ok, i used the right ones then. Excellent! Thank you for the quick reply Spencer.

odonnell

http://www.clarks-garage.com/pdf-manual/cyl-03.pdf

Is this information for the early 944 superseded then?