Thread: Timing - too advance? or too retarded?

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Hi Group -
Got a question about timing. Had a Rod shop pull my intake manifold, and replace the gaskets, because of a vacuum leak. They pulled my distributor, and reset the timing.
Just got it back Friday, but can't do anything about it until Monday, but when starting, it cranks slow and then speeds up. Also, when I accelerate, you can hear the valves ping alittle.
Too advanced, or too retarded? I use high octane gas. Thanks

Sounds to me like your base timing is a bit too advanced. The 'ping' is minor detonation, often caused by too much advance or fuel with lower octane than you're tuned for. You need to baby it until you can get it checked, minimize the ping as much as you can.

If they set the timing to stock configuration......and you are using high octane fuel......you may need to advance the timing by 2-3 derees specially if the block is built up to run on premium fuel. If its built up to run on regular 87 octane you will need to retard the timing by 2-3 degrees.

The slow cranking and pinging tell me too far advanced. I just went through some of your posts and found you have a 350 sbc engine, retarding it is the easiest thing in the world. First, take a permanent marker and put a little line on the distributor body where it meets the block, and continue that line a little on the block. You want that for reference so you know how far you have retarded it.

The rotor turns in a clockwise direction in a sbc so to advance the timing you turn the body of the distributor counter clockwise, and to retard the timing you turn the body clockwise...........that is what you want to do. Now, take a 9/16 box wrench and slightly loosen the clamp at the base of the distributor, enough so the body can be turned. TURN THE BODY ONLY A VERY SMALL AMOUNT in the clockwise direction (just maybe a 1/16 of an inch from the reference marks lining up) and tighten down the clamp bolt. Now crank the engine and see if it turns faster. If it does, take it for a ride and see if the pinging is gone. If it still pings, or if it cranks slow yet, loosend the bolt, turn the body just a tad more clockwise, and try it again.

You don't need to turn the distributor body very far to effect a lot of change in the timing. I rarely use a light and go by feel and sounds. I just take it advanced until it cranks slow and keep retarding it until it runs right. You can also use a vacuum gauge, but that is a different story altogether.

Don

Don's advice is spot-on for technique, but if you've got computer controlled timing (ECM/ECU) I would suggest putting a light on it to get the base timing where it's supposed to be. Also, higher octane fuel slows the burn rate to limit ping in high compression engines running more advance - seems to me if you're getting "ping" under acceleration there is no way your timing is retarded (needing more advance), IMO. If it's retarded a few degrees you won't see max power and it may run a bit hotter (especially your exhaust headers) but it'll crank quick and won't ping. Just my thoughts (and been wrong before....)

Thanks for all the advice. I don't have a timing light, but before the manifold was removed, it cranked fine, and there wasn't any ping at all.
I'll make a mark, as you all suggested, with a marker on the manifold, so I'll know
how much I moved the distributor. Thanks again for your imput.
Mike

If you're going to be running high performance engines, a good timing light and a vacuum gauge is a necessity IMO. Dropping the timing back so it doesn't ping is probably ok for today, but I'd be for either buying a timing light or having someone set it that does have a good light. Takes tools to maintain a car, a timing light and vacuum gauge are probably two of the more priority items you'll need to keep things tuned up.

Since you know its wrong now, there is no need to mark it yet---adjust it , check with timing lite for future referance AND THen maybe mark it

The only reason I suggested marking it first is because you know how sometimes the distributor turns a little when you loosen the clamp, if he marks it first he can make sure it is still in the original position and go from there. It just gives him a positive way to know his starting point, plus it will give him a way to know how far he is turning the distributor until he finds the sweet spot. If there is no mark to reference off of you wonder "did I turn it enough or not", by actuallly seeing the original mark you know how far you have gone each time.

Don