Cam lobe wear. How much is too much

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VeryValiantVellow

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My crank gear problem is resolved. So here is second question. Calipers on the lobes of a CC 564 lift cam says I have up to 14 thousandths variance in height. Comp Cam says 2 to 3 is maximum. Do you agree. Replacement time? The engine has very low miles on it. Probably less than 2000. Is this wear likely the result of improper adjustment upon installation or poor oiling? Insights?
What the heck. Third question: Installing new hydraulic lifters with adjustable rockers. Before the lifters are pumped up, that means, upon initial installation and adjustment when I tighten down the adjustment stud, I have been going down until contact between lifter and rocker are achieved then adding an additional half turn. On fresh rocker I could keep turning until the spring in the lifter is compressed. Someone tell me how do you do it to get zero lash?
 
My crank gear problem is resolved. So here is second question. Calipers on the lobes of a CC 564 lift cam says I have up to 14 thousandths variance in height. Comp Cam says 2 to 3 is maximum. Do you agree. Replacement time? The engine has very low miles on it. Probably less than 2000. Is this wear likely the result of improper adjustment upon installation or poor oiling? Insights?
What the heck. Third question: Installing new hydraulic lifters with adjustable rockers. Before the lifters are pumped up, that means, upon initial installation and adjustment when I tighten down the adjustment stud, I have been going down until contact between lifter and rocker are achieved then adding an additional half turn. On fresh rocker I could keep turning until the spring in the lifter is compressed. Someone tell me how do you do it to get zero lash?
Comp sells cams so of course their numbers will be low. .002-.003 isn't much wear. No wonder why they sell a lot of cams. What does it look like? photos are a must here. The wear pattern tells a lot.
 
I bet if u measured it new it would be off 4 to 6 thou. Dam near every lobe will be different. The last cam I installed was pretty much right on except it was 4 though bigger than the spec.post some pics. Kim
 
I always adjust with the up and down method. Hold the pushrod with your fingertips moving pushrod up and down lightly as you slowly tighten rocker. When you feel no gap go an additional 1/2 turn.
 
Dad
Summit shows a new Comp with .525 lift, which is the step down Dick was talking about for $157. They have it in stock. I can help you with some of the cost, probably can come up with $100.
 
This is the second time this engine has been apart. The first time was due to the oil pump not being tightened up, so it ate some crank bearings. I reinstalled the cam because it looked in excellent shape and mic’d good. Since then, my dad, VeryValiant...has acquired the engine. It ran great with the exception of it wouldn’t idle worth a crap, probably due to the carb being sketchy. He put a new 2X4 intake on it and it somehow got a bit of H2O in it. Waiting on results of the conditions of rods and mains. Can’t help him figure it out cuz I’m in Texas, he’s in Florida....
 
My crank gear problem is resolved. So here is second question. Calipers on the lobes of a CC 564 lift cam says I have up to 14 thousandths variance in height. Comp Cam says 2 to 3 is maximum. Do you agree. Replacement time? The engine has very low miles on it. Probably less than 2000. Is this wear likely the result of improper adjustment upon installation or poor oiling? Insights?
What the heck. Third question: Installing new hydraulic lifters with adjustable rockers. Before the lifters are pumped up, that means, upon initial installation and adjustment when I tighten down the adjustment stud, I have been going down until contact between lifter and rocker are achieved then adding an additional half turn. On fresh rocker I could keep turning until the spring in the lifter is compressed. Someone tell me how do you do it to get zero lash?
Replace it.
Once cams begin to wear the degradation of the lobe will accelerate and will happen quickly.
You may want to invest in a quality cam (not CC) if you dont want to see the inside of the engine again. The hard part to making a valve train to live is usually not the cam but the lifters. Good luck finding quality hydraulic lifters.
 
Cam lobes are measured by subtracting the base circle diameter from the maximum diameter.
The exhaust and intake lobes are likely different. I would think all intake lobes would be within a few thousandths. Same for the exhaust lobes.
 
Dad
Lunati
SKU
10200507
Close to Comp number
 
If you are replacing the cam and have adjustable rockers I would put a solid flat tappet with EDM lifters in. 30K on my XS274S Comp Cam 340 and I shift at 6200 every pass.
 
You know there is slope ground into the face of the lobe. If you measure one side versus another and the base circle is smaller on the smaller and larger on the higher, your measurements are going to be skewed.
 
I still would like to see the cam lobes.

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maybe the high end toolsteel or coated ones
IDK if anyone even does their own edm
edm sizes vary
I've run adj lifters with hyd lifters lots of times
Krooser looked into lots of lifters for our Jones circle track cam, and the Howard back up
with hyd I'd run the Crower or total seal lube saver lifters
 
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