Trying to find timing.

I bought one of those SEARS triming light with the adjustable timing knob on the back of the gun.

On a pre-1987 Chevy 350,

RMP 700
Vaccum Advance disconnected.

Hooked up to spark plug number one.

I have to turn the knob to 40 degree advance in order to have the timing mark at 0.

The engine runs great, runs on normal gas and stuff.

The idle is 450.

What am I doing something wrong ?

Thanks in advance.

The idle could be a different problem then the timing. The low idle could be caused by low amounts of fuel being injected, a bad idle control module, or other things. I would just suggest you double check those before you reset your timing again.

good luck, im trying to rebuild a 350tbi so i'll probably have similar problems, lol

No I set the idle to 450 for normal engine operation but I check the timing at 700 rpm as per the book.

Thanks.