My CompCams Cam Card ECL Question
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My CompCams Cam Card ECL Question
Hello. I ordered and received my camshaft from Comp.
I gave them these specs:
239 intake @ .050
254 exhaust @ .050
114 lobe separation
110 intake centerline
Which should work out to:
ivo 9.5
Ivc 49.5
evo 65
evc 9
However my cam card valve timing @ .050 read:
ivo 9.5
ivc 49.5
evo 64.9
evc 9.1
Which would put the lobe separation at 113.95 instead of 114 degrees Which is stamped on the end of the camshaft.
I haven't installed the cam yet, thus I haven't degreed it.
Why the apparent discrepancy with my specs?
Thanks in advance.
I gave them these specs:
239 intake @ .050
254 exhaust @ .050
114 lobe separation
110 intake centerline
Which should work out to:
ivo 9.5
Ivc 49.5
evo 65
evc 9
However my cam card valve timing @ .050 read:
ivo 9.5
ivc 49.5
evo 64.9
evc 9.1
Which would put the lobe separation at 113.95 instead of 114 degrees Which is stamped on the end of the camshaft.
I haven't installed the cam yet, thus I haven't degreed it.
Why the apparent discrepancy with my specs?
Thanks in advance.
-Poppy
Re: My CompCams Cam Card ECL Question
IF these numbers are accurate we are talking about 0.05° i wouldn’t loose any sleep about it
Re: My CompCams Cam Card ECL Question
Everything has a tolerance.
Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Re: My CompCams Cam Card ECL Question
If the numbers are indeed accurate I'd see it more as confirmation of good QC than some kind of error
If my maths are correct you're talking 1 / 7200 of a circle, or 3 minutes, which is a very small amount and I'd guess well within tolerance
If my maths are correct you're talking 1 / 7200 of a circle, or 3 minutes, which is a very small amount and I'd guess well within tolerance
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Re: My CompCams Cam Card ECL Question
On my previous CompCams I just never seen them put the exact precise degrees on my cam cards.
You all are correct in saying that it's in acceptable tolerance and is nothing to worry about.
You all are correct in saying that it's in acceptable tolerance and is nothing to worry about.
-Poppy
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Re: My CompCams Cam Card ECL Question
5 minutes ... really?
The width of a line on a degree wheel is more than that.
The width of a line on a degree wheel is more than that.
http://www.rmcompetition.com
Specialty engine building at its finest.
Specialty engine building at its finest.
Re: My CompCams Cam Card ECL Question
The cam card is odd and precise. I would check that cam with a wheel for sure. I assume it was a custom grind? Close to a Crane F-278-2 solid flat tappet but just a bit more exhaust timing. Cast iron exhaust manifolds maybe?
I have an old Isky cam with rounded up valve timing numbers on the card. I guess it was to avoid decimals in the spec from confusing people, but who knows?
I have an old Isky cam with rounded up valve timing numbers on the card. I guess it was to avoid decimals in the spec from confusing people, but who knows?
- mt-engines
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Re: My CompCams Cam Card ECL Question
.05 X 60 = 3..... 3 minutesWalter R. Malik wrote: ↑Mon Mar 18, 2024 10:17 am 5 minutes ... really?
The width of a line on a degree wheel is more than that.
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Re: My CompCams Cam Card ECL Question
So ... even less, LOL.mt-engines wrote: ↑Mon Mar 18, 2024 11:38 am.05 X 60 = 3..... 3 minutesWalter R. Malik wrote: ↑Mon Mar 18, 2024 10:17 am 5 minutes ... really?
The width of a line on a degree wheel is more than that.
http://www.rmcompetition.com
Specialty engine building at its finest.
Specialty engine building at its finest.
- mt-engines
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Re: My CompCams Cam Card ECL Question
The tip of the pointer lolWalter R. Malik wrote: ↑Mon Mar 18, 2024 11:41 amSo ... even less, LOL.mt-engines wrote: ↑Mon Mar 18, 2024 11:38 am.05 X 60 = 3..... 3 minutesWalter R. Malik wrote: ↑Mon Mar 18, 2024 10:17 am 5 minutes ... really?
The width of a line on a degree wheel is more than that.
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Re: My CompCams Cam Card ECL Question
That’s pretty close. I wonder if any perceivable difference would be even measurable on a dyno between those two specs. Probably within the margin of error to be even picked up.
Re: My CompCams Cam Card ECL Question
i wonder how close itll be to the card when you degree it.
"Anyone who thinks the low RPM engine will be faster just does not have as much experience as the rest of us" -The late, great Joe Sherman.
You wont beat anyone if you do everything the same as everyone.
You wont beat anyone if you do everything the same as everyone.
Re: My CompCams Cam Card ECL Question
Extended high RPM power band normally.
Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
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Re: My CompCams Cam Card ECL Question
I bet actual running duration changes 5-10* from spec’ed just by virtue of system flex.Roundybout wrote: ↑Mon Mar 18, 2024 1:06 pm That’s pretty close. I wonder if any perceivable difference would be even measurable on a dyno between those two specs. Probably within the margin of error to be even picked up.
-Bob
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Re: My CompCams Cam Card ECL Question
What you are interpreting as a "discrepancy" I would interpret as excellent quality control and probably have some doubt about its accuracy until I put a degree wheel on it.
That would require a very large diameter wheel that is extremely accurately marked to be able to read that close, also coupled with a high quality cam drive system if cam is installed in an engine.
That would require a very large diameter wheel that is extremely accurately marked to be able to read that close, also coupled with a high quality cam drive system if cam is installed in an engine.