I recently finished building my high-compression d16a6 build. It uses relatively stiff valvesprings (65 lbs seat, 170 @.450 lift)--Anyway the motor only has about 3 hours of run time, it now seems like the timing belt is a bit looser than when I first set it up. Is this a normal occurance? Do you have to re-tension the belt after a little bit of run time? Anybody with some direct experience please respond, I appreciate it--Jay.