so i'm installing a new tfs stage 2 into my fox, and either i'm doing it wrong, or my math is all fubared.
installed it (so i thought) straight up, crank sprocket has 9 keyways, used the 0 one just by eye.
card specs at .050" lift @ lifter are
intake 5 btdc 39 abdc max 107 atdc 224 duration
exhaust 53 bbdc -1 btdc max 117 btdc 232 duration
my first time thru i got:
intake 10 btdc 40 abdc max 105 atdc 230 duration
exhaust 50 bbdc 4 btdc max 120 btdc 234 duration
so looked 2-3 degrees advanced on centerline, and an extra few degrees duration. looking at my sprockets again, it looks like i used the 2A keyway somehow, so i reinstalled it back to the 0 key and tried again, which is where it gets weird.
next readings:
intake 0 btdc 48 abdc max 114 atdc 228 duration
exhaust 50 bbdc -4 btdc max 113 btdc 234 duration
looks like somehow my intake went from being 2 degrees advanced to 7degrees retarded (and lost 2 degrees duration?) and the exhaust went from 3 degrees retarded to 7 degrees advanced.
so is my math just screwed, am i just doing this wrong, or do i just need to move it the other way?
installed it (so i thought) straight up, crank sprocket has 9 keyways, used the 0 one just by eye.
card specs at .050" lift @ lifter are
intake 5 btdc 39 abdc max 107 atdc 224 duration
exhaust 53 bbdc -1 btdc max 117 btdc 232 duration
my first time thru i got:
intake 10 btdc 40 abdc max 105 atdc 230 duration
exhaust 50 bbdc 4 btdc max 120 btdc 234 duration
so looked 2-3 degrees advanced on centerline, and an extra few degrees duration. looking at my sprockets again, it looks like i used the 2A keyway somehow, so i reinstalled it back to the 0 key and tried again, which is where it gets weird.
next readings:
intake 0 btdc 48 abdc max 114 atdc 228 duration
exhaust 50 bbdc -4 btdc max 113 btdc 234 duration
looks like somehow my intake went from being 2 degrees advanced to 7degrees retarded (and lost 2 degrees duration?) and the exhaust went from 3 degrees retarded to 7 degrees advanced.
so is my math just screwed, am i just doing this wrong, or do i just need to move it the other way?