Distributor keeps adding advanced without stop?

[LivewireBlanco]

So I replaced my points distributor with a remanufactured electronic distributor and mopar ignition module. Replaced my heavy spring in distributor with a light one and noted I have a 15 on my advance plate, should have 30* mechanical advance.

So I set my initial timing at 8 and plug my vacuum advance and as I rev the engine it keeps adding advance as the rpms rise going all the way to 60, which is as high as my timing light goes. What the heck is going on here? Car drives good and surprisingly no pinging on 87 octane.

 

[67Dart273]

Just throwing lighter springs on a stock smogger distributor is not the answer

Even if it's right you have at least 38 (8 + 30) which might be too much without vacuum. What kind of light? I've seen "dial up" lamps that were inaccurate and generally refuse to use them.

What I ALWAYS do to an unknown engine is start first with a piston stop and make sure TDC is correct, or remark the balancer.

What are you using to determine advance? Example if you are using timing tape it might be for the wrong diameter balancer.

If you want to recurve the distributor on the cheap, look up FBO Mopar advance limiter plate. These seem to work fairly well for the money.

So far as your problem you need to first know that you have the balancer marked right, and a good timing light. So far as the distro it could be a mix and mismatch of parts...................................................

 

[RAT ROD AL]

I'm not so sure an engine will even run at 60* adv. But i can tell you if it will , it won't like it.

 

[Garrett Ellison]

Indeed, I have seen this before. It may sound okay and you may run with no audible pinging, BUT you will overheat and if you run it long enough you will begin to deposit piston material on your spark plugs. (Ask me how I know!) Having shortened slots and all that it entails in distributor advance plates, I recommend the much easier FBO plates to limit your mechanical advance.

 

[LivewireBlanco]

Im wondering if it's not my cheapo timing light. I know the balancer is right cause I marked it at tdc when I assembled it. It's running great and not over heating. My old distributor had 16.5 marked on it so this is a slight improvement but I'll get the FBO plate eventually.

 

[1969383S]

Im wondering if it's not my cheapo timing light. I know the balancer is right cause I marked it at tdc when I assembled it. It's running great and not over heating. My old distributor had 16.5 marked on it so this is a slight improvement but I'll get the FBO plate eventually.

Maybe not.

I used a later model points (reman) distributor with FlameThower III and initially got numbers approaching 60. It must have been a lean burn dizzy originally. Regardless the 383 was not happy, welded up the diagonal slots just using a simple printed from the internet paper 360 degree template with a hole cut in the center for reference on the total mechanical advance. The particular motor setup as configured does not like part throttle with the vacuum advance so I blocked it with a BB/ball bearing. Total is now 35/36 with one light spring with 18 initial and the 292/509 motor loves it. Full advance by 2000. Controlled my temps at cruise and the motor has great response across the board.

Make sure the dizzy you have is compatible with the FBO plate before buying one!

 

[Garrett Ellison]

I too prefer timing tape or positively marking the balancer as posted elsewhere on here with a static timing light. Dial back timing lights are okay if you can afford a high end one, but I am weary of how delicate some of the electronics appear in a lot of the newer ones.

 

[1969383S]

If it matters all I run is Non-E REC90. I might add some octane boost every 5 tanksfulls.

 

[LivewireBlanco]

Well it was marked 15r so I thought it'd be 30* advance. It's a reman of a original mopar unit so FBO unit should fit.

 

[1969383S]

Well it was marked 15r so I thought it'd be 30* advance. It's a reman of a original mopar unit so FBO unit should fit.

Mine was not and would have liked to use that plate instead of welding slots. Think they only work with straight slotted advance gear.

 

[1969383S]

Pertronix does not or did not make a plate for my Mopar Electronic dizzy. That’s Why I went to a points unit. If I could have checked them prior to buying I would have picked one that had the straight advance gear slots so I could use the FBO plate. I have run orange, chrome and Gold units since the early 80’s. I have never been happier then with what I run now. Just took a little effort to dial it in. Was more concerned with the looks and it all is very nicely hidden to appear as stock. No unsightly boxes and extra wires.

 

[RustyRatRod]

I'm not so sure an engine will even run at 60* adv. But i can tell you if it will , it won't like it.

Sure it will. Including vacuum advance it's not uncommon at all. I bet some of what you have driven has had that much with vacuum included. But he is saying excluding vacuum and that' pretty high.

To the OP, that "15" is in distributor degrees, I bet. Keep in mind distributor degrees is half of crank degrees so to get 30 crankshaft degrees, the distributor would indeed be 15, so that's probably correct. If it runs good, I bet like Del said, your light is possibly reading incorrectly.

 

[krazykuda]

Indeed, I have seen this before. It may sound okay and you may run with no audible pinging, BUT you will overheat and if you run it long enough you will begin to deposit piston material on your spark plugs. (Ask me how I know!)

Hos do you know????

 

[halifaxhops]

15 R on the cam plate = 30 at the crank it will not go past that. Prob the timing light is wacky. LA engine?

 

[Mattax]

Indeed, I have seen this before. It may sound okay and you may run with no audible pinging, BUT you will overheat the piston and if you run it long enough you will begin to deposit piston material on your spark plugs. (Ask me how I know!)

Yes. Too much advance under loaded conditions will have detonation that burns spark plug electrodes and piston crowns. Its always good to check the spark plug porcelain for tiny shiny specs of aluminum.
This will not show as more heat into the cooling system. Late timing will put more heat into the cylinder walls (piston is further down the hole during combustion) and into the coolant.

I too prefer timing tape or positively marking the balancer as posted elsewhere on here with a static timing light. Dial back timing lights are okay if you can afford a high end one, but I am weary of how delicate some of the electronics appear in a lot of the newer ones.

Part of the problem is the slew rate.

Maybe not.

I used a later model points (reman) distributor with FlameThower III and initially got numbers approaching 60. It must have been a lean burn dizzy originally. Regardless the 383 was not happy, welded up the diagonal slots just using a simple printed from the internet paper 360 degree template with a hole cut in the center for reference on the total mechanical advance. The particular motor setup as configured does not like part throttle with the vacuum advance so I blocked it with a BB/ball bearing. Total is now 35/36 with one light spring with 18 initial and the 292/509 motor loves it. Full advance by 2000. Controlled my temps at cruise and the motor has great response across the board.

Make sure the dizzy you have is compatible with the FBO plate before buying one!

Part throttle pinging is a common problem with vac advance when shortening the outside of the slots.
When using vac advance, shorten the inside and use the heavy secondary spring.

 

[LivewireBlanco]

15 R on the cam plate = 30 at the crank it will not go past that. Prob the timing light is wacky. LA engine?

Yes, 318. I went ahead and ordered the FBO plate since I'll benefit from it anyways. Is it possible to assemble the distributor to where it will advance non stop?

 

[Garrett Ellison]

Hos do you know????

Having to set timing by ear in a pinch on a slant 6, drove said vehicle until overheating became evident. Was running way advanced. Just like Mattax said, shiny silver dots on plugs...

 

[Mattax]

Yes, 318. I went ahead and ordered the FBO plate since I'll benefit from it anyways. Is it possible to assemble the distributor to where it will advance non stop?

In practice, yes. Use heavy enough spring or springs and timing will continue to advance to redline.*
If you look at the advance curves of pre-smog engines, the more efficient low rpm engines have a long curve that follows rpm.
If you look at the pre-smog curves of the higher performance engines, they advance quickly and then have a somewhat long slow curve.

*Its really only useful to have it advance to power sweetspot.

 

[Max1196]

Does your timing light have multiple functions? As in, is it set on the setting to check an engine with "coil packs" instead of the basic version. Or is it set on 4 cyl instead of 8? Just a thought!

 

[LivewireBlanco]

Does your timing light have multiple functions? As in, is it set on the setting to check an engine with "coil packs" instead of the basic version. Or is it set on 4 cyl instead of 8? Just a thought!

No switches, just a dial. It's a cheap Harbor Freight light. Im going to try swapping it out today and see what another one says.

 

[Garrett Ellison]

No switches, just a dial. It's a cheap Harbor Freight light. Im going to try swapping it out today and see what another one says.

Who else is saying "Problem Solved!"? I do quite a bit of shopping at harbor freight myself, so am by no means passing judgement (Some their stuff I am even partial to!), but I have had my share of take back to trade in as well.

 

[67Dart273]

If it's a "dial up" light..........and a cheap one...........I'd scare up a plain old no nonsense "light." I've bought a couple at garage sales. I STILL HAVE my old Penske I bought in the early seventies!!!

Like this one............stolen photo off the www

 

[halifaxhops]

In practice, yes. Use heavy enough spring or springs and timing will continue to advance to redline.*
If you look at the advance curves of pre-smog engines, the more efficient low rpm engines have a long curve that follows rpm.
If you look at the pre-smog curves of the higher performance engines, they advance quickly and then have a somewhat long slow curve.

*Its really only useful to have it advance to power sweetspot.

Matt I think he means to infinity. In that case no.

 

[AJ/FormS]

Lite set on 2-cycle? or is it a 2-cycle lite ?
It is highly unlikely to be 60 plus mechanical... because the spark will be desperate to be jumping to the next tower.

On another note;
Most street engines will want a total cruise timing (and also whenever lightly loaded) of 52 or more degrees at somewhere between 2200 and 2600, occasionally even 56*, at slightly higher Rs. During testing, for instance,my 367 has not complained about 60*@ 2250@ 62mph. In most cases the factory D will not provide this.

 

[MopaR&D]

Long ago I had a cheap dial-back timing light, it kind-of worked until I put a Mallory CD ignition box in my car then it didn't work right at all. I bought a fairly cheap non-dial-back one from a parts store and have been using that since along with marking the crank damper up to 60* BTDC. I did it to a stock damper once by carefully turning the crank and cutting a slot every 10 degrees, more accurate and permanent would be to stick on timing tape and use that as a template to cut slots in the damper.