total timing reading accurate with no load?

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adam83

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I have a completely stock 1986 318/727 from a ram. I converted the ignition over to electronic with a Standard LX101 ignition control module and stock replacement vacuum advance distributor WPS brand, all for a 1975 318 from parts catalog.

Got everything hooked up and engine runs beautifully and starts up easy. Right now the initial timing is set at 7 degrees at 730rpm, set with vacuum advance plugged and the car in gear and my son's foot on the brake. Tried to check total in gear as well but couldn't get the car past 2200rpm in gear. Maybe due to the lock up converter, so I couldn't check total timing.

Now, with my dial timing light, and the car in park, I still got about 7 degrees initial, but I'm not seeing 34 degrees until around 3000rpm. And the weird thing is, it keeps advancing the more rpm I gave it. I think it was around 46 at 4000rpm.

I'm a little rusty on timing, but I thought once the distributor reached it's total mechanical advance the timing would stay at there for the rest of the engine rpm range. Why does mine keep rising? Is it normal because the engine is in neutral with no load? Or is it a distributor issue? Maybe the advance mechanism I'm my dizzy is broken or not secured correctl
 
You need to limit the advance in the distributer.

Either weld the slots or get an FBO limiting plate.
 
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When you go up to 3000-4000 do you still have the vacuum can disconnected? Stock distributors don't really have a good limit to mechanical advance. This is why the old school method is to disassemble it and weld the advance slots smaller. Now, we have the advance limiter plate from FBO. It's a nice piece and well worth the money for the whole kit that includes the springs too. But again, the distributor will have to come out and apart. It's not a hard job and is well worth the money and trouble. You can find info about it here.

How to limit mechanical advance in a mopar distributor, tuning for street, strip or all out racing, cure that rich stinky idle, win races
 
Yes this is all with the vacuum advance plugged.

Well taking the distributor back out is easy I'm not worried about that, but I don't know if this brand of distributor has the same internal mechanisms as a Mopar distributor, not sure if that plate would work. It's a World Power Systems DST3890. Ill pull it off and check it out.

Am I correct though that the timing should any more move once the mechanical advance is reached? Or will it continue to rise a little with engine room?
 
adam83 said:
Yes this is all with the vacuum advance plugged.

Well taking the distributor back out is easy I'm not worried about that, but I don't know if this brand of distributor has the same internal mechanisms as a Mopar distributor, not sure if that plate would work. It's a World Power Systems DST3890. Ill pull it off and check it out.

Am I correct though that the timing should any more move once the mechanical advance is reached? Or will it continue to rise a little with engine room?
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If this is your distributor, WORLD POWER SYSTEMS DST3890 Distributor | RockAuto then it appears that yes, it is a Mopar style unit and the limiter plate will work. Yes, the advance will "eventually" stop advancing, but in order to acheive a good, decent, performance curve, you will need to limit it further, based on how much initial timing you have.

One example I can give is, most times, stock compression small blocks can take "around" 20* initial and "about" 34* total. In other words, 14* mechanical advance. A good place to start would be 12* initial and bump it in increments of 2*. As long as the engine continues to pick up RPM as you advance the initial timing, the engine is tellin you it wants more. When you find the point at which advancing initial timing makes no difference in RPM, that's the most initial it wants. Then you can install the limiting plate accordingly. As long as you let the engine tell you how much initial timing it wants.
 
No load is the normal way of checking as it relies on RPM's.
Fine tuning the vacuum advance is done under a load because vacuum varies under load due to throttle opening.
Vacuum advance tuning is done more by ear while driving the car.

The problem you are having is as thesiren74 says, that you need to limit your total mechanical timing.
The reason is that the factory advance setting is usually 0 degrees or TDC and the distributor is made so that 0 degrees the advance should be close on the total.
When running more initial the distributor lets your timing go well over the recommended total.
Hope this explains things clearer.

The limit plate from FBO (4secondsflat.com) has selectable slots that limit the distributors advance weights and therefore limiting the total advance the distributor can throw in as your RPMs increase.
I have used these extensively in building performance distributors for Mopars.

You might also check into the performance advance spring kit while you have the distributor open anyway.
This kit allows the advance to come in sooner than your 3k by using one spring in the kit to replace the heavier of the two springs in it now.
Your total should be all in around 2.5k with this spring installed.

Mr. Gasket Distributor Advance Kits 925B here:
Mr. Gasket Distributor Advance Kits 925B

Here is the address for the limit plate:
How to limit mechanical advance in a mopar distributor, tuning for street, strip or all out racing, cure that rich stinky idle, win races

If you have a Paypal account you can send $22 to sales@4secondsflat.com with your shipping info for a J685 Mopar limit plate.
Or just call Don at 541-942-5920 and get one that way.
 
But remember, 22 bucks only gets you the limiter plate. You also need the advance sprAngs. No way in hell would I pay 12 bucks foe ONE pair of springs. That Mr Gasket kit is the lamest ever.
 
RustyRatRod said:
But remember, 22 bucks only gets you the limiter plate. You also need the advance sprAngs. No way in hell would I pay 12 bucks foe ONE pair of springs. That Mr Gasket kit is the lamest ever.
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What a d**k :D
I read your post from yesterday about the radiator a few min ago and couldn't stop laughing.

Anyway, at least the kit comes with two springs so it can do two distributors.
Is there a better option I am not aware of?

Hope you two feel better soon.
 
TrailBeast said:
What a d**k :D
I read your post from yesterday about the radiator a few min ago and couldn't stop laughing.

Anyway, at least the kit comes with two springs so it can do two distributors.
Is there a better option I am not aware of?

Hope you two feel better soon.
Click to expand...

The kit I got a few years back had like 4 or 5 pairs of springs and the plate. And yeah, I just caint help myself sometimes. lol

EDIT: I got the kit with the plate and six springs.
 
RustyRatRod said:
But remember, 22 bucks only gets you the limiter plate. You also need the advance sprAngs. No way in hell would I pay 12 bucks foe ONE pair of springs. That Mr Gasket kit is the lamest ever.
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So true.

The Mallory kit had 9 springs in it. If I could find one complete kit with all the springs in it, I'd snatch that up in a New York second and send them to a spring manufacture and have them either duplicate them, or supply them to me with springs that are equivelent.

The MSD kit is garbage too. 3 springs. Light, medium and heavy. What junk.
 
I have a peanut can full of various distributor springs. lol compliments of the old man.
 
fishmens67 said:
I have a peanut can full of various distributor springs. lol compliments of the old man.
Click to expand...


I used to have a bunch of them, but somewhere in the move from the west side to the east side put them in the lost column.

If I had the original springs from Mallory, that I like, I can have a company match them up. If they can't match them, they can make them.
 
yellow rose said:
So true.

The Mallory kit had 9 springs in it. If I could find one complete kit with all the springs in it, I'd snatch that up in a New York second and send them to a spring manufacture and have them either duplicate them, or supply them to me with springs that are equivelent.

The MSD kit is garbage too. 3 springs. Light, medium and heavy. What junk.
Click to expand...

Isn't it funny how non Chevy people always get the shaft? Or not funny.
 
Thank you for replies I'm pulling out my dizzy and starting there. I'm not understanding why my timing just keeps increasing and never settles. I'll update what I find. If it all checks out I'll order the plate and springs
 
Yup - it will advance until the slot stops it. Shorten the stiff spring, or weld up the advance slots and it will stop.
 
When I wanted to buy a limit plate, I emailed Don using the sales email address @TrailBeast posted. Don emailed back asking about my combination. Then he gave me suggestions on which slot to use and what to set initial timing to get it close. Customer service to the max!!
 
adam83 said:
I have a completely stock 1986 318/727 from a ram. I converted the ignition over to electronic with a Standard LX101 ignition control module and stock replacement vacuum advance distributor WPS brand, all for a 1975 318 from parts catalog.

Got everything hooked up and engine runs beautifully and starts up easy. Right now the initial timing is set at 7 degrees at 730rpm, set with vacuum advance plugged and the car in gear and my son's foot on the brake. Tried to check total in gear as well but couldn't get the car past 2200rpm in gear. Maybe due to the lock up converter, so I couldn't check total timing.
Click to expand...
This is normal. Nothing to do with the lockup. That's the torque converter's brake stall speed. You couldn't have even put it gear with a standard transmission without doing a burnout or stalling.
Now, with my dial timing light, and the car in park, I still got about 7 degrees initial, but I'm not seeing 34 degrees until around 3000rpm. And the weird thing is, it keeps advancing the more rpm I gave it. I think it was around 46 at 4000rpm.
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That's could be correct. All Chrsyler distributors continue to advance well above 3000 rpm. A stock 318 will have a quick increase off idle and then a long steady secondary advance. How many degrees the advance increases depends on the initial specified for that engine.
I'm a little rusty on timing, but I thought once the distributor reached it's total mechanical advance the timing would stay at there for the rest of the engine rpm range. Why does mine keep rising?
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Because Chrysler engineers and techs wanted to provide the best cylinder efficiency and power through those higher rpms. But 46* is quite a bit high. Did you have a the vac advance plugged? If not, that's the answer.
Is it normal because the engine is in neutral with no load?
Click to expand...
The mechanical advance relates only to rpm.
The vacuum advance relates to load.
 
I see thank you.


I ordered the plate and springs, and they ain't cheap anymore! $69..

I've taken apart the WPO distributor. The slot plate that came with it doesn't even fit over the weights properly, and there are some hefty springs on the weights. I don't think the sloted plate was even stopping the weights.
 
adam83 said:
I see thank you.


I ordered the plate and springs, and they ain't cheap anymore! $69..

I've taken apart the WPO distributor. The slot plate that came with it doesn't even fit over the weights properly, and there are some hefty springs on the weights. I don't think the sloted plate was even stopping the weights.
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If you are talking abou the FBO plate, yes they often stop the advance before the long looped, heavy spring is engaged. That's why its generally better to weld up the inside of the slots. Points distributor for drag racing this isn't as important. But for any electronic distributor and for almost every other use, engaging the heavy spring is better.

Here's how and why is pretty well illustrated with Rockable (360 Tune Up) and further discussed with Mullinax.
 
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My experience is the dizzy quits advancing about 8,000 rpm. So does everything else....
 
I got my limiter plate and springs set in the mail. Don recommended that I put the initial at 16 and mechanical at 18, and put the vacuum to manifold and adjust the can until I have 30 initial
 
Got my plate and the 2 silver medium springs installed. I put in plate as suggested, on the 18 slots. After warmed up with no vacuum advance my initial is at 16 and at 3200rpm+ it stays at 34 degrees. Engine seems really happy with it.

I then played with the vacuum pod hooked to manifold vacuum, (had to 'customize' an allen wrench to fit past the oil pressure sensor) and after SEVERAL counter clockwise turns I was able to achieve 30 degrees at idle (originally was at 40 with vacuum). Rechecked initial and mechanical with vacuum unplugged and they were same at 16 and 34. Hooking everything back up and then test driving.

2 Questions:
What should I have my idle speed set at with these new settings?
My full mechanical advance doesn't reach 34 degrees until about 3100rpm. Is that too high? I'd rather not go through the hassle of replacing springs again if this is acceptable.
 
You can go with Don's method, but I can't help you there.

Chrysler timing should look something like this on a stockish 4 bbl engine
upload_2020-1-19_14-40-4.png

if you check the Rockable thread linked before, you can see my plot of a MP distributor on my engine.

and mild 2 bbl 318 more like the non-CAP timing shown here
upload_2020-1-19_14-42-24.png


At idle the mixture should be relatively rich (assuming emissions control is not goal, but economy is)
therefore no vac advance at idle.
There should be vacuum advance when driving on the highway that brings the timing to roughly 50* BTC

see
How To Limit and Adjust Chrysler Vacuum Advance Cans
 
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