jtranger

My '61 FI 315 HP with duntov cam Has approx 8000 mile on the rebuild and has new plugs, cap rotor with a pertronix igniter. While idling, I can hear and feel a slight pop coming out of the right exhaust pipe. There is no noise on the left side. The only thing I could think of was possibly that a lash adjustment was needed on the right cylinder bank 2,4,6,8. Any idea's of whats causing this and is this normal with a duntov cam? Engine experts please chime in. Thanks

jammovette

sounds just what my 390 hp 66 BB was doing this past week. Found out lobes on cam on left were so worn out they were mushroomed and had to force cam to get it out. Exhaust valves were not opening enough and causing a popping noise just as you indicated. Had less than 8,000 miles on the motor. have you been using zinc additive or oil with zinc? I wasn't good luck

muncieman

It's not normal for it to pop with that cam or any other cam that GM made, and I'll leave it there

mayordaly

If it doesn't feel like a miss while driving, it may be just a bad exhaust
manafold gasket or even a small head gasket leak at the exhaust port,
you wouldn't feel anything while driving. You may feel it at the exhaust
pipe when comparing left and right. if its a head gasket it will get worse
and may get to overheating also.