I think that the 2000 GSR motor has 10.2 or 10.0 to 1 compression. I am not exactly sure and it is 3:30 in the damn morning and I don't feel like looking. If I was to get a thinner head gasket. Let say the thinnest one possible and still be safe. What would my compression be?

 

just use a stock head gasket
using a thinner one will only change it by .1 or .2
not enough to make a noticable diffrence.

 

Compression is 10.0:1 and using a thin headgasket will raise your comp. to 10.2:1