Timing Mark issues - Nothing lines up...

[Chryco Psycho]

I would not use the vacuum advance at all .

[nqkjw]

You need to pull some timing out to stop it from pinging.
If it won't start or runs like crap down low after you pull timing out then your dizzy curve is too wide.Not uncommon with today's crap fuels.
If you've masterd your timing light the do as Chryco suggested.Get all your total timing in by 3000rpm.Then check your initial.I like to see 14-16 initial.Even as high as 18 can be acceptable.
If you can't get the timing to sit as described above you'll have to recurve your dizzy.

A couple of years ago someone on here or FABO had much the same problem.Turns out he had a dizzy from some sort of truck from a junkyard which would have been from a super low compression engine and therefore too wide a curve.

[74 challenge]

I would not use the vacuum advance at all .

So if I unhook the vac advance and it runs without pinging just go without it? I am looking for mpg so I just assumed I need the advance.

What is your opinion on reg gas vs running premium?

Nqkjw:
When I try to pull out timing the engine develops a stutter when I accelerate it bogs down and kind of buck, idle goes a little crazy. The disto is brand new.

[nqkjw]

Vacuum advance is a fuel economy part.Nothing else.
When vacuum rises(foot off the throttle or lean cruise)the vac adv gives you more timing.
The more timing you can get into an engine(without adverse effects)the better your fuel economy will be.
So your reasoning is correct.However,it would appear you have too much mechanical advance.So when your vacuum pulls in you are over advancing causing pinging.
Chryco is right(as usual )If you can get it happy without the vac adv then just leave it off.That's the easy way out although it's not quite desirable.

Re reg vs premium.you won't get any advantage out of premium unless you have enough compression to warrant premium.There's a lot more to it than JUST compression but compression is the main one.I'd say very roughly abt 9.5:1 is around where an engine could be happy with either.

Even if the dizzy is brand new the curve may not suit your engine.It sounds to me your curve is too wide by the symptoms you describe.

[Got JOB]

Just a thought. Either the timing cover or the balancer is not the correct one. Earlier model small blocks timed on the passenger side. When the engine is at TDC, look at the balancer on the fuel pump side and see if you see the mark. If this is the case, you can fab a pointer to mark TDC and time it. I think there was a timing marker that bolted to the timing cover for this purpose. You could also mark your balancer when you find TDC and time off your mark.

[Bullitt-]

     Leave the Vacuum advance disconnected until you get the car running correctly without it.
Here's something to contemplate later on. Is it possible you are connecting the vacuum line to the wrong connection on the carb? There is one that sees little to no vacuum(ported) at idle that the vacuum advance connects to, others see manifold vacuum and will pull the advance on at idle. Using the wring one obviously keeps things confusing. 



What kind of issues were you having that caused you to replace the distributor in the first place?

[Got JOB]

Here are some pics to better show my last reply. If your balancer is earlier part, you are about 80 degrees off from the timing mark, if it is on the drivers side.

[74 challenge]

Nqkjw: I see what your saying about the disto but even if it were the wrong one could I just adjust the vac advance Allen key counter clockwise to get it better? I asked people on here before I bought the disto no one ever said it was incorrect, plus summit says good for all late 60's to 86 318's. next time I'm at the garage I am going to try removing the advance and see what happens I'll keep you posted.

Got job: this is news to me. I'll check this the previous owner trusted this car to a "know mopar mechanic" and boy oh boy he was great at doing everything wrong. The past 3 years have been fixing mistakes made by this guy. I for sure have cast in timing marks on the drivers side of the block. Are there any significant differences in the balancer that would easily give it away?

Bullitt: it's for sure on the timed port on the carb. It's an edelbrock 1405 it's using the left side vacuum port if you are facing the engine.

Could the engine be going lean? The p.o. Adjusted the carb last. I did the whole air mixture thing but it could easily be wrong too.

[Bullitt-]

Bullitt: it's for sure on the timed port on the carb. It's an edelbrock 1405 it's using the left side vacuum port if you are facing the engine.

Could the engine be going lean? The p.o. Adjusted the carb last. I did the whole air mixture thing but it could easily be wrong too.

Time to invest in a vacuum gauge & do it right http://automotivemileposts.com/garage/v2n8.html

[74 challenge]

Time to invest in a vacuum gauge & do it right http://automotivemileposts.com/garage/v2n8.html

I think your right. I'm in over my head I think. Now where to find a vacuum meter on a Sunday night. Do I hook this gauge up to timed vac or constant?

[Bullitt-]

I think your right. I'm in over my head I think. Now where to find a vacuum meter on a Sunday night. Do I hook this gauge up to timed vac or constant?

Well around here you can pick one up at any of a dozen auto parts stores.. For carb tuning & timing use manifold/constant vacuum

[74 challenge]

Well around here you can pick one up at any of a dozen auto parts stores.. For carb tuning & timing use manifold/constant vacuum

I'm going to give this a try tomorrow, I'm entered in a car show on Tuesday night.

I'll keep you posted.

[74 challenge]

It's working well without the vac advance, a light ping under acceleration but it seems to be the best I can get it. I think the vac advance still needs tuning but its too damn close to the intake to fit an Allen key in there. I said enough is enough and made it work without.

The vac gauge was a huge help.

[Bullitt-]

        Have a good time at the show.