HELP!!!!

Was the miss there before the new plugs, cap, and rotor?

Big Chris

And......is it missing at idle, at city speeds, at highway speeds, under acceleration, under deceleration..............we need details man!

Doc

Lost a lobe on the camshaft. 305's are notorious for this. That is where my money is. Put a vacuum gauage to the motor and see how bad the gauge flucuates.

Funny, I've never head of this being a problem on the 305's.

Doc

I have seen 6 personally with a lobe worn round. From what I remember the worn lobe was on 7 or 8 (cylinder) this I do not remember for sure. All had the same symptoms. So you could see why I would think "notorious". Think is has something to do with people not changing oil regularly and then no lube on the lobe. So I guess you would be right...it is NOT the 305's fault...it would be the folks who don't take care of the motor. It would be cheap and fairly easy to yank the intake and have a look see though.

John

It ACTUALLY was a batch of bad 305's. No amount of maintenance was going to keep them from going flat. I don't remember if it was the rods on 7 and 8 put in backwards or just bad cams, but it did happen to almost all of them in a certain batch.

I used to make machines that harden camshafts.

All they had to do was screw up the setup for a few days and not catch the soft lobes. It would take awhile before people begin to notice.

I didn't think I was that far off. What years were that batch? I figured there was a slew of them if I alone saw 6. I remember some 1984-85 trucks that I did with this problem. Thanks for the info.