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Discussion Starter · #1 ·
I took this camshaft out of my 454 rebuild , basicly the engine never ran right and I put new
Pistons and new rings in 060 oversized into it ,
Found out it might had low or no oil at some stage . The engine had maybey several other issues including bad oil pickup that was too high also the oil pump might have been faulty …
Anyway can you please
Let me know what you think
About the cam .. it’s : cd103062
13-05-03
 

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IF you have a vernier caliper or even a dial caliper, you can compare intake to intake, exhaust to exhaust all along the cam. Looks like there are at least two lobes worn down more than the others. My just be the pictures and the lighting/aspect/angle/me, but the cam looks pretty fried on its way out. Low ZZDP is my guess on the break in.

Tire Automotive tire Wheel Sports equipment Rim
Missing much of the nose in this and other lobes...
 

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Notice how the lobe looks flattened at the nose? The polished area is where the face of the lifter rides. The lifter is supposed to spin as the cam rotates and the spinning keeps it from wearing in one spot. The ramp of the lobe up to the nose and then back down (opening ramp then nose [highest lift] then closing ramp) to base circle (lowest part of the cam [no lift] when valves are closed). Looking at your lobe's noses, some are worn far more than others from what I can tell by the pictures. This is typically caused by a failed break-in period and/or running the cam with low or no ZZDP additive in your oil. Flat tappet cams require lots of ZZDP and even then, some camshafts manufactured these days (and many lifters) are total crap and wear out even if you do everything perfectly. Here's a real old thread here on SNS that helps explain (don't listen to the people saying we don't need ZZDP, they're complete idiots and have no scientific basis for their rants, only their personal bias from what they've "read/heard").

Good read:

Enjoy, and hope this helps :)

~Andy
 

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Another thing you can do is look at the face of each of the lifters (hoping you kept them in the order matched to the cam lobe they followed) and see the correlating wear on the face of the lifter to the worn lobe nose. That will help. If the lifter is cupped in any way, it's toast. The spinning in their bore keeps them flat. You can use a straightedge to check these with a light behind it and rlay the straightedge across the diameter of the face on the "flat" side and if you see light, it's toast.

I may be totally wrong and the pictures are just tricking my eyes but they look bad to me. Tough to tell but a caliper would tell all... and looking at the lifter faces.
 

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Discussion Starter · #12 ·
Just put my normal calipers on there on each of them shows different measures.. I guess it’s worn out then… new camshaft it is … next question what camshaft can I put in there ? Obviously that camshaft was running in there before , so basicly what of the specs on the new camshaft MUST be matching to not have any problems ?
 

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If you have the specs on the cam and the motor worked well at one point, I would stick with the same cam or something really close so no valve spring changes, no piston to valve interference, same powerband, etc. Jetting the carb, ignition, all those things...
 

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Lift, duration, lobe separation angle, everything if you don't want to change anything else. Otherwise, as long as you don't go higher on the lift, you can make it work but you may have to do a bit of tuning to get it running well. Really depends on what you are after as far as performance. Do you have the original cam specs? Looks like this is the one:

 

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Cams and lifters and and bearings are not that expensive. Why risk it --- replace all of them while you have engine apart and out! Personally I would not use that cam. You chance the engine not running well and even loss of power. I would not want to take the engine apart to replace these after you have put it back together and back into the vehicle. If you are asking you know there maybe a problem --- good luck to you! I love this site ---there is so much expertise on here!
 

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One question, what heads are on the motor and what valve springs are installed? Max open/closed seat pressures, max installed height, significantly affect how a cam can wear. If the heads were built for a roller cam, the spring seat pressures are typically much higher than for a flat tappet cam and will destroy the lobes and lifters in short order. Lots of things to work/figure out before slapping a new cam back in the motor...
 
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