valve clearance
Thread Starter
1st Gear
Joined: Mar 2017
Posts: 1
Likes: 0
valve clearance
hi
i install xfi series comp cams . 546 ex lift and 550 intake lift (with 1.6 rocker arms )
258 int and 264 ex duration @0.50
with afr heads 0916
flat top piston with 2 valve relief 7cc
when rotate engine all exhaust valve hit center of piston
whats wrong
i install xfi series comp cams . 546 ex lift and 550 intake lift (with 1.6 rocker arms )
258 int and 264 ex duration @0.50
with afr heads 0916
flat top piston with 2 valve relief 7cc
when rotate engine all exhaust valve hit center of piston
whats wrong
Le Mans Master
Joined: Apr 2013
Posts: 5,376
Likes: 1,118
With that amount of information, it's hard to say. Could be lots of things that would cause or contribute to that:
- As pointed out above, cam phasing out completely;
- too little deck clearance;
- heads shaved too much;
- lots of duration, which you have;
BTW: Do you really have 1.6 rockers?? All LS series engines come with 1.7:1 rockers, except the LS7, which has a 1.8:1 rocker ratio. At 1.7:1, your exhaust lift would be around .584" lift, which should be fine with stock heads and deck heights and reasonable duration. That cam has a hell of a lot of duration though, so who knows?
- As pointed out above, cam phasing out completely;
- too little deck clearance;
- heads shaved too much;
- lots of duration, which you have;
BTW: Do you really have 1.6 rockers?? All LS series engines come with 1.7:1 rockers, except the LS7, which has a 1.8:1 rocker ratio. At 1.7:1, your exhaust lift would be around .584" lift, which should be fine with stock heads and deck heights and reasonable duration. That cam has a hell of a lot of duration though, so who knows?
