Thread: strange compression loss

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i have had my 352 running since the middle of this summer and have since put about 4000miles on it. i havent had any problems at all and it still runs great but i noticed a little of a power loss. i decided to do a compression test and got 150psi across the board with the excpetion of cylinder #1 it is only making about 90psi. the reason for me checking the compression is that i heard a noise that sounded like a small exhaust leak coming from the passenger side. it made that kind of tick and sounded like sort of like an exhaust leak. well the collector was leaking a little and i tightened it up, but the noise was still there so i did the compression check. it doesnt sound like a bottom end noise, its a valve train noise. i checked under the valve cover to see if there was any damage visible. and i saw nothing. the motor has new springs, puchrods and lifters. could it be a collapsed lifter or something. i know there is no way to adjust the valves on an FE so i dont thats the problem. other than that it runs great. any sugesstions would be great since this is my daily driver and i hate driving it like this i really dont want anything to mess up.
thanks
tyler

Sounds like you dropped an intake cam lobe, and the valve is not lifting high enough for that cylinder to get a full charge of intake air into it, hence the low compression.

My 10 cents worth

that scares me haha it doesnt run rough and it ran fine for 4000 miles and it still runs fine, i broke it in right and from my understanding cams usually fail during break-in if they are gonna fail, im not trying to argue with you im just hoping for the best. wouldnt it run rough if it dropped a lobe? also wouldnt i find metal shavings in my oil filter? i always check for them and i havent seen any, i changed the oil about a week after this noise started im gonna go home and pull the valve cover and see if the springs on that cylinder compress as much as the others if the lobe is gone then they shouldnt compress as far

im gonna try that right now