Cam Lift Question

[1EVIL88VERT]

SO i need to know if my valves will hit, and taking off the heads is not an option. I have edelbrock performer RPM heads and a lunati 51014 cam it's 500./510 lift and duration is 218/226 at .050 this is with 1.6 rockers and i have no problems ....but i want to switch to 1.7 rockers. I have stock pistons and i need to know if anyone has a similar or bigger cam with stock pistons and no issues, oh and the heads have 1.9 and 1.6 valves......

 

[1EVIL88VERT]

bump...

 

[maverick0716]

Impossible to tell unless you use the clay method. 1.7's would give you about .535-.545 lift on that cam.

 

[69Rcode_Mach1]

I would highly caution against not checking. Its worth some head gaskets and 10 minutes to save your engine from failure. The hardest part of getting the intake and such off is already done, heads are cake just take them off. If you don't want to do you remember how much clearance you had when you first put the engine together with the 1.6 roller rockers if so do a little math and subtract see where you fall.

 

[2002BLGT]

Impossible to tell unless you use the clay method. 1.7's would give you about .535-.545 lift on that cam.

its actually .531 / .542 and yes anything over .520 on stock pistons on any bolt on head will probably hit .........stay with the 1.6s and you will be fine .....

 

[1EVIL88VERT]

damn....i guess i hit another speed bump on the quest for more power....anybody want some 1.7 stud mount rocker?.....what will be the next mod?....hmmmmm

 

[maverick0716]

its actually .531 / .542 and yes anything over .520 on stock pistons on any bolt on head will probably hit .........stay with the 1.6s and you will be fine .....

Duration is as big a factor as lift is.....most people don't even look at duration when guessing P to V clearance. There may be milder cams out there that will clear with .545 lift and some more aggresive cams that won't clear with only .520 lift.....It's so hard to tell that the only proper way to do it is check with clay.