Thread: Timing questions

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Well, the new builder will have my motor ready for me by the end of the week. I have a question about setting the timing. Here is my combo :

70' Chevelle SS w/ a 470 ci. Ported Merlin rectangle port heads, 13:1 JE pistons, Lunati solid roller .685"/.692", Coan built 400 w/4500 stall.

I have a MSD billet distributor w/o vaccum advance. It has a total advance of 21 degrees. I am going to run 116 race gas. How do you guys recommend I set my timing? Once again, I am new to the carburated/Non-EFI world. Therefore any other advoce you have would be great!

Brent

try 1 " less mercury than max vacuum.

Originally posted by 306bullet
Well, the new builder will have my motor ready for me by the end of the week. I have a question about setting the timing. Here is my combo :

70' Chevelle SS w/ a 470 ci. Ported Merlin rectangle port heads, 13:1 JE pistons, Lunati solid roller .685"/.692", Coan built 400 w/4500 stall.

I have a MSD billet distributor w/o vaccum advance. It has a total advance of 21 degrees. I am going to run 116 race gas. How do you guys recommend I set my timing? Once again, I am new to the carburated/Non-EFI world. Therefore any other advoce you have would be great!

Brent

if i was you id ask the guy thats building the motor. what ever he told me is what id do as long as he had anything to do with it anyhow

I NEVER time by vacuum - particularly on a race engine. Ask the engine builder how much advance should be in your distributor, and when it should all be in. Make sure it has that curve, because any old distributor curve won't work on your engine. Then put on a timing tape (unless you have a degreed balancer.) Rev the engine up to where all of the advance should be in, and set the timing at the spot the engine builder told you.

Example . . . if he says 36 degrees (and I'm not saying 36 is the correct number - just an example), and it should all be in by 2500 RPM, crank to 2600, set it at 36, and let the initial fall wherever it wants to. In your case, it should drop back to 15.

Initial timing means squat on a race engine. It's the curve and the max that makes it all work.

Well I have talked about it with my builder about the timing. It's not that I won't take his advice, I just wanted to hear more than one opinion. This is what my builder told me to do:

I would set your base timing around 10-12 degrees and your total timing at 34-35 degrees. I would set your distributor to have all it's advance in by about 3000 rpm. You may be able to run slightly more initial advance than this which is ok as long as you don't have a hard time getting it to start. But make sure your total doesn't go over about 35 degrees.

I have been talking with others locally, and they pretty much say the same. I have already recurved my distributor and adjusted the amount of advance it will allow. I think I am good to go. We'll see what happens. Thanks for your ideas and thoughts!

There ya go. He gave you good advice.

Originally posted by 306bullet
Well I have talked about it with my builder about the timing. It's not that I won't take his advice, I just wanted to hear more than one opinion. This is what my builder told me to do:

I would set your base timing around 10-12 degrees and your total timing at 34-35 degrees. I would set your distributor to have all it's advance in by about 3000 rpm. You may be able to run slightly more initial advance than this which is ok as long as you don't have a hard time getting it to start. But make sure your total doesn't go over about 35 degrees.

I have been talking with others locally, and they pretty much say the same. I have already recurved my distributor and adjusted the amount of advance it will allow. I think I am good to go. We'll see what happens. Thanks for your ideas and thoughts!

i like that engine builder