28-04-02, 09:32 AM
Ok I put a copper head gasket on an 87 spg with the apc mod, borla exhaust,20psi blow-off valve. Now i took it out for a test run and got the car up to 120 or so and came home and no leak beautiful the cooling system had the reg pressure that it normally builds up thats it! but then i took it out again and only got it up to 105 and i went to see and the coolant now bubbles! so i removed the valve cover and retorqued the head bolts to 90 then the extra 90degree turn (1/4 turn) and ran it the same as before and now its loose again? can i put locktite on the head bolts or will it help or should i torque the piss out of it or not????!!!!!!
28-04-02, 09:58 AM
Whatever you do dont overtighten the head bolts, for some reason they are not clamping down the head enough, the most likely reason is they are either over stretched or the combination of the (thinner?)copper gasket and the possibility the the heads been skimmed now means the original bolts are too long before reaching the bottom of the block holes (tightening them any further will definately break them if this is the case)- did you use new head bollts or not?
I would first of all try new head bolts and see how you get on
As copper head gaskets aren't readily available in the UK not many of us have used them over here.
There is experience with their use in the States, and judging from the comments on Saabnet most people have had the same trouble as you and gone back to the standard head gasket.
28-04-02, 04:41 PM
ok well then my question is will an OEM head gasket keep boost pressures of up to and over 20 psi or not if not then what do the people who are running boost well over that have as far as a gasket in their motor?thnks for all the replys i will try new head bolts no i didn't use new ones.
Eric van Spelde
29-04-02, 07:46 AM
If the block and head are true, you are not experiencing detonation or overheating and with new head bolts tightened as per the instructions, a stock Elring gasket should hold up just fine to even ludicrous boost levels (20+ psi). If that's not enough, O-ringing the block should prove a better approach than a copper head gasket.
check out this link about head tightening...
29-04-02, 09:29 PM
I appreciate it i have the same thing in my Haynes repair manual torque steps and all but thnks.