Hi Dave,
What R33 a/f meter's are you refering to, gtst?
If yes i havn't herd of these being an upgrade, I've herd of R32 ones being used. I don't know how you would set this up with the PFC, maby power intake? :confused:
Also the R33 gtst afm's are 80mm and the standard GTR afm's are 65mm so they won't bolt straight up you'll have to customize the piping if you were to do this.
I would stick to the options that the PFC give's to you, Z32 AFM or Q45 AFM's theirs plently of z32's going around fairly cheep $250ea but once again you will have to modify you'r intercooler piping Z32 = 80mm & Q45 = 90mm.
Their is a nismo afm that bolts straight up also.
Nat