Cam Lift Question

1EVIL88VERT

New Member

Jul 12, 2004

314

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Dyess AFB, TX

Jun 8, 2005

#1

• Jun 8, 2005

• #1

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

New Member

Jul 12, 2004

314

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Dyess AFB, TX

Jun 8, 2005

#2

• Jun 8, 2005

• #2

bump...

 

maverick0716

Founding Member

Jan 12, 2002

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Chilliwack, BC, Canada

Jun 8, 2005

#3

• Jun 8, 2005

• #3

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

 

69Rcode_Mach1

Active Member

Apr 20, 2004

1,473

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37

Salt Lake City, Utah

Jun 8, 2005

#4

• Jun 8, 2005

• #4

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.

 

2

2002BLGT

Well-Known Member

Dec 18, 2003

2,945

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59

Bedford VA

Jun 8, 2005

#5

• Jun 8, 2005

• #5

maverick0716 said:

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

Click to expand...

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

New Member

Jul 12, 2004

314

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Dyess AFB, TX

Jun 8, 2005

#6

• Jun 8, 2005

• #6

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

Founding Member

Jan 12, 2002

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Chilliwack, BC, Canada

Jun 8, 2005

#7

• Jun 8, 2005

• #7

2002BLGT said:

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 .....

Click to expand...

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.