Anybody have any experience with a cam that has whipped out lobes? I would suspect that it would make some valve train noise at the very least. Would it just not fill the cylinder properly, causing the car to not accelerate well, limiting the wide open RPM? Or, would the car still tach out freely, only accelerating very slowly?
I would expect a lot of valvetrain noise, and you will see it in a compression test. Any engine will rev out in neutral unless you have a major exhaust restriction.
Are you sure Larry? Lifter noise, yeah I could see that. But a compression test, I'd think that could read normal and the valves remain closed.o No: I would expect POOR performance would be the 1st sign. I have never experienced one either though.o No:
Re: Are you sure Larry? Depends on which valve was remaining closed, intake or exhaust. I think if you put a dial indicator on each lifter and measure the lift, you would know for sure. A wiped lobe should make alot of noise, the valve lifter bottom would be damaged and the lifter itself would have no preload, and would be unable to take up the lash. I think this is simply a tuning problem. You need different jetting and timing at altitude.
Normally a wiped out cam will have noise, since you will now have slop inthe valve train. A flat exhaust lobe will often give you a popping back through the carb as the burnt gasses have no place to go but back out the intake valve. A flat intake will just be a possible loss of compression and power loss. You can easily tell by taking off the valve covers and starting the engine and just watch the valves, also check for excessive looseness. Jim Burek
Scott, At first the car seemed to lose power, then as the cam got worse it started popping back through the carb, at anything above idle. When I removed the camshaft it had 2 lobes that looked like baby main journals. This all took place within 100 miles or so. I had to completely clean out the motor and start again. The next cam was fine and ran good for years. This was in a 74 Corvette with a 350 4-speed, but I am sure a buick motor would act the same. Duane
You might want to drain some oil and run a magnet through it. I think it may be time to pull her back out and check everything. With so few miles you can reuse most of your gaskets and may save a lot of valuable parts. I have had so many pulls and reinstalls on my 84 Lesabre I have got my remove time down to 3 hours, working alone.
