Initial timing set @ 30*. Engine seems happy?

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Corrupt_Reverend

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Freshly rebuilt 318, rv cam (Don't know specs of cam)

When I first got my new engine running a week or so ago, we just timed it by feel.

After a little messing, the idle seems smooth around 570-590 rmp. This is with the timing at ~30*. It will still idle if I back it off, but it's more "burbly" (which I kinda like, but whatever.)

Does this seem about right?

FWIW, it gets pretty toasty after cruising around for a bit. Don't know if that has anything to do with timing, or if the factory radiator+after market finger chopper fan is more at fault.

Thanks in advance for any input! :)

~Rev.
 
I agree with the above.

Also, when timing it, did you get this reading with the vacuum advance unhooked and plugged at the carb???
 
If you own a vacuum gauge use that to set your initial timing. That will give you a good starting point.
Here's how it's done. Hook your gauge up to a non ported manifold vacuum source. Then advance or retard your distributor until your get the highest reading on the gauge . Then turn the distributor the other way until the vacuum drops 1" to 1.5". This will be your initial timing setting.
While 30* does sound a little on the high side it is possible that's what it wants.
Ted
 
Isn't the harmonic balancer keyed to ensure proper index? The balancer on the engine has the timing marks stamped in it @ 2* intervals. I'll double check anyway, but I didn't think it could go on wrong.

I don't have a vacuum gauge. Could I use my timing light to advance until the RPM is the highest, then retard a little? Or do I need a vac gauge To find it proper?

Thanks for all the help so far! :)
 
The balancer hub is keyed to the crank. That does not stop the outer inertia ring from slipping on the hub if the rubber ring is old, deteriorated or otherwise defective. That's why you were advised to check TDC. 30* initial is a gob of timing. Way too much, unless you have it locked out....even then not a great idea for a street car.
 
You can pick up a vac. gauge at the auto parts store. They're not very expensive. It's a real handy tool to have in your tool box. it's a big help when you start to tune your carb also.

Ted
 
mine liked 38 initial.... 68 340 on pump premium 12sec street car on street tires ..#'s OEM untouched long block..
 
Are you absolutely certain your timing light isn't picking up a second signal from the #3 wire ? Mine will do that if the pick clamp is too close to the other wire , this doubles the reading on the light . Whats the total when your driving it if you've got 30 initial , hard to believe it's not detonating like crazy when it advances from there if you do .
 
Dusted74:

I do need to adjust my carb. Guess I'll pick one up tomorrow.

ph23vo:

Now that you mention it, I was wondering if I should be using a higher octane fuel. The guys I got the engine from said the compression was 9.something:1. I know that's higher than stock. I haven't had any pinging, but I'm pretty sure I'm running a bit rich.
 
cannucky:

Wouldn't double pick-up cause the timing marks to be jumpy? It appears pretty rock-solid, but I'll check again this evening.

Edit: And I don't know what it is while driving. It doesn't ping. How would I check that?
 
Anything in the 30's should be over all timing in my experience with the small blocks. Usually about 20 is what you want to see for initial assuming your cam is installed straight up and balancer is good.
 
Isn't the harmonic balancer keyed to ensure proper index? The balancer on the engine has the timing marks stamped in it @ 2* intervals. I'll double check anyway, but I didn't think it could go on wrong.

I don't have a vacuum gauge. Could I use my timing light to advance until the RPM is the highest, then retard a little? Or do I need a vac gauge To find it proper?

Thanks for all the help so far! :)



You are correct in that it is keyed for proper index, but that is provided you have the correct balancer and it has not moved like RRR said. You need to find TDC on #1 and verify your timing marks line up.
 
Double checked everything. One mistake I made was @ 30* the idle is sitting at 600.

I brought it back to 22*. The idle drops to 520, but it still idles fine and fires on the first crank.

Should I try advancing past 30* and see if I can get the idle up, leave it at 30*, leave it at 22*, or try backing it even further off?
 
Also, when timing it, did you get this reading with the vacuum advance unhooked and plugged at the carb???
 
I would check the balancer like RRR said. I can't imagine it would even start with that much initial without kickin back.
 
The idle speed is adjusted at the carburetor, not the distributor.
 
Hilarious

I wasn't trying to be funny at all. He made no mention of adjusting the carburetor and only talked about the difference the distributor timing made with the idle speed. Probably should be idling around 750 or so, btw.
 
I know the idle is adjusted at the carb. But it also changes a bit with ignition timing doesn't it?

I don't know a whole lot about this sort of thing so I thought maybe the idle might be an indicator as to how close the timing is.

Should I bring the idle up with the carb while the ignition is @ 22* and try again from there?
 
Idle and timing are two separate animals.

Yes, idle will change when you adjust the timing. When you do change it you should adjust the carb back to base idle, say 750 - 800.

You NEED to check the balancer to be sure it's accurate. Piston stop at TDC and see where the mark is on the balancer. Then you will know for sure if you are setting it where you think you are.
 
Thanks Bad Sport. I think I understand now. :)

Won't have anyone to help me get it to tdc until Tuesday so I guess the dart will have to stay parked for a couple days.

Just to make sure, my new order of opperations should be:

Make sure timing mark is correct.

Set timing ~20*.

Adjust the idle to 750-800 using the carb.

Then should I advance from 20-ish until ping, then turn it back a bit or should I just leave it alone and find a grown up? :p
 
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