The Stovebolt Site Forums The Shop Area Engine Shop setting the timing

could someone tell me how to set the timing on my 235 chevy ,, i do drive it now and things seems fine but i dont think the horse power is there ,, i do know about the BB on flywheel ,, i do have a timing light ,, i do know about the oct setting too ( i have it on 0 now ) where should the BB be in compared to the indicator on block , just above it or below it ,,i do have a vac gauge too just dont have anyway to set rpm ,,,

thanks guys

I would set the BB to the pointer to start with. You will probably end up advancing it a little more but start there.

Denny, GM was calibrating the timing of these engines for the fuel that was available at the time. I find that with today's fuels they run better advanced approx 5 degrees extra.

That's been my experience as well.

Even if you know that the flywheel you have is the right one for your engine, setting timing to the ball lining up with the pointer usually only provides a rough timing setting - good enough to get it started (either by static timing, or by using a timing light).

I have found the most reliable "final" setting (on a 216/235/261) is obtained with a vacuum gauge (maximum vacuum at idle on a warmed-up engine), or by setting close to the engine pinging under load. Adjust the timing to the engine, not to a setting (and, it also saves having to buy a 6v/12v timing light).

The bonus of having/using a vacuum gauge on these old engines, it the vacuum gauge is also useful for setting carburetor idle mixture (for one carb, or for multiple carbs).

hey dav
you say advance 5 deg now where would the BB be then just above the marker or below ,, my car runs well now were it is i just wanted to make sure its the best it can be ,, thats why i wanted to know by turning the dizzy clockwise is that advance ???

thanks guya

On most of the ones I work on I set the ball about half way between the pointer and the bottom of the opening.
To advance the timing you turn the distributor counter clockwise.
Three things can happen from advancing the timing to far. Pinging, bucking on the float, or kicking back against the starter.

Not to iterupt the conversation but I'm running about 8-9 degrees and she seems to run ok. Now for me to run vacuum the only place to hook it it up would be going into the carburetor from the vacuum advance,would this be correct in doing so? it's the only place I have..

At idle, you do not need the vacuum advance, so you could connect the vacuum gauge there.

Do you have a vacuum wiper motor? If yes, you could use that port on the intake manifold.

Great advice guys!! I have a brand new/rebuilt Carter 2100 on a 235 and it was bucking and losing power under load. I thought I had carb problems. So after reading this post, I just retarded the timing a hair since it was also pinging under load. So lilrobo, if u do the above steps and it pings, just retard it a bit. I had originally got the highest vaccum reading but apparently it was advanced too much.