folks,

my 70 camino (stock 402 with HEI and edlebrock 750 carb) has always had a slight vibration during idle (approx 650 rpm in park) since i got it(4 years ago). if i increase the RPM from 650 in park the vibration increases, then around 1300 rpm it seems to diminish. when you put it into gear, no vibration. perfectly smooth. runs great. new cap, rotor, plugs, wires, module, coil, connectors and capicitor this spring, vibration still there. 18" vacuum at 650 rpm.

any ideas? i was wondering if it was the trans (maybe torque converter). the trans does whine a bit, and the previous owner installed a shift kit that i used to feel (hard shifts), now i don't feel anymore.

what do you think?

Maybe a small vacuum leak? Dave

O,
18 inches of vacumm at idle sounds pretty healthy.Whats the cam specs ?Might want to drop the trans inspection cover and check the torque converter bolts for looseness.While your there take a good look around the crank mounting bolt area for cracks.
I had a DD Buick with a slight vibration at 40 to 50 MPH that I chased for about 2 yrs.Finally found a cracked flexplate when I replaced a leaking front seal and vibration was gone.

thanks guys. let me start with the easiest thing first. when i check the vac gauge, it does show 18" but it does bounce around. is this normal? should it bounce around???? (bounce meaning maybe +/- 1/2").

what do you think?