924Board.org

[bradelporsche]

Well after finding out I had low compression on cylinders 1 and 2 I decided to take the head off.

This is what I found



Anyone know what brand these are? Also noticed the head centering sleeves are missing. Are these normally left out when head studs are fitted?

I'm thinking about taking these off and going with OEM bolts and find replacement head sleeves? Does anyone have any laying around?

[bradelporsche]

Also anyone know the torque specs for these?

I made sure they were torqued to 76 but after doing some research they should be torqued down to 90 ft lbs or close to 110nm

[MikeJinCO]

If you need the sleeves, I made some once as they are NLA and could walk you thru it. It takes a small drill press, a bunch of bits, some 1/4" pipe and a mini grinder. Plus a bunch of fiddling and fitting.
_________________
Mike


'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

[fiat22turbo]

Keep the studs. They tend to work better. That said, I'm not sure of the brand except they aren't ARP since those have finer threads and a hex in the top to thread them in more easily. You could notch the tops to make them easier to thread in and out. I suspect the torque specs would be similar to stock but would be more evenly distributed with the studs.

Unfortunately, head gaskets will always fail eventually just due to the different expansion rates of steel and aluminum. Faster if you have a cooling issue of course. Make sure the surfaces are very clean and smooth to help reduce tearing of the gasket over time.
_________________
Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[bradelporsche]

Thanks for the info guys.

I think these may be the raceware head stud version.

The head gasket itself looked fine. The head is suspect. Cyl 1 intake valve guide looks as if it moved down towards the valve.

Dropped of the head at C&M Machine

[pmcaya2]

[pmcaya2]

I agree with fiat22 about keeping the studs - you can use a thread gauge to measure the pitch and a die to clean-up the threads, making sure to keep the shavings out of the cylinders.

As far as the head goes, You're right to take it to a good automotive machine shop and have them give it a look. Like surgery, you want someone who does it all the time.

I believe that 90 ft-lbs is correct but I'll check - I think I used the Haynes manual for that info.

[peterld]

Those headstuds do indeed look like the early version of Raceware headstuds. Later versions had a screwdriver slot in the top, while ARP have hex slots.
Definitely keep the studs as they can be re-used, while headbolts are theoretically one use only.
As you obviously did not fit the studs initially, I would be inclined to pull the studs and run a tap down the holes to ensure correct depth and cleanliness, before reassembling with correct stud lube. While you are at it, run a die over the stud threads.

Unfortunately you will have to make the locating sleeves, but they are not ctitical to reassembly. Though to be sure, to be sure, I prefer them.
_________________
80/81 932/8 ROW

[jason c]

You can remove & install the studs with the double nut method. I would definitely clean them up. I would definitely use the locating sleeves if they'll fit with the studs to minimize head movement. Retorque after 1K miles is required for stretch bolts. The retorque of head bolts is part of the 30k mile service, but I would do it sooner on a car that isn't routinely driven. The headstuds should be reusable and being so, would not be "stretch". It will not hurt to retorque, just don't loosen them.
I would also recommend retorquing head bolts more often on cars that experience extreme ambient temperature changes.