Having problems getting a smooth idle from my rebuilt Olds 215 with

a slightly larger camshaft. Vacuum gauge shows steady 12 - 14 reading

in the area that says "late ignition timing". The timing is already an inch

ahead of the timing tab on the engine into the area of (no numbers).

Max on the tab is 10 BTDC.,and when I advance beyond that the vacuum

gauge still remains in the 12 to 14 range with rising idle speed.

Is there an initial setting that goes beyond stock when using a larger

cam? I can't believe I can advance it much farther without causing

damage at higher engine speeds.

Returned timing back to approx.20 to 25 degrees (guessing). Adjust-

ed idle screws and speed,and now have a slightly rough idle at about

800 rpm. What force is at work here?

 

After some work with the timing and idle speed screws,I've readjusted the

timing to approx. 7 degrees BTDC. Turned up the idle speed screw,and

readjusted the idle bleed screws at the base of the carb.

Also cleaned and installed a set of hotter spark plugs because the others

where carbon fouled from too rich choke setting running too long.And

long periods of idling while checking timing,idle speed,ect. Engine runs

better and now has a slight lope due to the new camshaft.

It appears that I was on the wrong track with the advanced timing

settings I was working with.