2000 grand prix GTP 85,000 miles car has been sitting in a garage for 4-5 years ,bought the car in pieces with a Stattama turbo setup. Rebuilt the engine with all new bearings, bolts and gaskets. Went with Cometic gaskets to handle the boost from the turbo. I just got the car running a couple days ago. I installed the gaskets with copper spray and torqued the heads to 35, 55, 70, 85, used thread sealant on ARP head studs. Tightened the studs finger tight until bottomed out.
Started car and it ran fine, AFR was around 11.5. I didn't get on the car at all with breaking in the bearings. Max boost I saw was 6 pounds. Weird part was the car would run idling and not over heat or miss. The only time I had a problem was when I was at highway speeds temps would get up around 210 running a 160 stat. Then the car would start to miss.
Finally I pulled the plugs and the number 1 cylinder plug was covered in white crap. Noticed coolant was down 1/2 gallon or more.
Just pulled the head. Hard to tell where the leak was from with the copper spray on the gasket.
