Advance springs

[Boduke]

Can someone point me in right direction with respect to distributor advance springs

Stock 318 /stock converter 904/273 rear gear.. driver.

The stock springs are smoked and im getting some mechanical advance at idle causing the timing to jump around.

I prefer a smooth idle. Here is what I am working with.. one soft and one heavy spring. See pics.. heavy is stretched out.

I idle about 700-750..

Looking for a starting point on what springs and where to buy.

Ive searched and the choices are exhausting. Just looking for recommendations on what works for mostly stock setup. Maybe a little hotter than stock

Thanks.

 

[Mattax]

Can someone point me in right direction with respect to distributor advance springs

Stock 318 /stock converter 904/273 rear gear.. driver.

The stock springs are smoked and im getting some mechanical advance at idle causing the timing to jump around.

I prefer a smooth idle. Here is what I am working with.. one soft and one heavy spring. See pics.. heavy is stretched out.

I idle about 700-750..

Looking for a starting point on what springs and where to buy.

Ive searched and the choices are exhausting. Just looking for recommendations on what works for mostly stock setup. Maybe a little hotter than stock

Thanks.

View attachment 1716248123

View attachment 1716248124

View attachment 1716248125

Good news. That's heavy spring is not stretched out. That loop is there on purpose. it causes the advance to slow down around 1600 rpm.

That and the slight angle on the plate is all part controlling the curve.

The small diameter spring maybe getting a bit stretched and this will effect when the advance begins.
Pull one from another distributor, or ask (not here! or moderates will shut the thread) for one and someone will have. They are not all the same but get one with the about same number of coils diameters and you'll be close.

However there are two other ways to add tension.
1. Bend the loop a little tighter. This is a bit tricky.
2. Turn the spring perch if its not already in the max ternsion position.
First time can be difficult and sometimes requires turning it from underneath, which in turn requires taking it out of the housing.
Photos in this post

 

[Boduke]

Brilliant!! Thought my big spring was wallered out. Good stuff! Thats just what i needed

 

[Mattax]

I should have mentioned another important factor in the spring force is the length, although I think you already figured that out.
The amount the primary spring has to be extended to get installed is what creates the force holding the weight from moving outward.

I may have some more pictures if needed. Certainly have some measurements of factory springs.

--
edit.
I detail what everything does in the posts here along with some photos of the factory springs

lets revisit timing

@RustyRatRod @Mattax Exactly. Welding the inside , extending the springs into more tension.. ...wtf is he thinking.lol so we want a slow curve? Putting the spring under tension and into its max resistance..uh no thanks. The outside is where you would close it up. Tony is a pants shitter No. I...

www.forabodiesonly.com

 

[Boduke]

your information is exaclty what i needed.. thank u sir!

 

[Boduke]

Another questin for the distr gods.. my magnetic pickup strip is not protruding out from the rubber housing box it lives in.(see pic) its flush. Is that in need of replacement or call it good. Ive seen photos of others where the metal strip pokes out a few thou.. im just trying to science it out before i re assemble it
Thanks agian

 

[Boduke]

Disregard last post .. you can push the plastic part back and the magnet will poke out inside the field

 

[Boduke]

so i swapped out the heavy sping for a medium spring. I got the thing to idle at 550 and super smooth.. runs way better mid range except there is now a nasty hole at roll in. As soon as i pumch it off idle it bogs bad! More pump or more initial? Im running edelbrock and i think im on the highest setting. Now at 10 ii
Imitial and ported baccuum

 

[Boduke]

Threw pump at it.. fixed…(almost) . Put edelbrock shooter in bottom hole..
I know i have to map the curve which i will do. But i wanna pound on it as is for a bit..

 

[Newbomb Turk]

You should have used the heavy springs and added more initial and then limited the curve.

 

[Mattax]

Don't ask me. I told you what the heavy spring was for.

 

[Mattax]

You should have used the heavy springs and added more initial and then limited the curve.

Yup. And if I knew before what the actual goal was, then you know what my suggestion would have been. That would have put more tension on the primary spring from the get go.

 

[Boduke]

Don't ask me. I told you what the heavy spring was for.

Bro but u seem to know the most. . Ok im gonna put heavy back in and then dial up tension on the post on then light spring. And put the pump shooter back how it was. I appreciate u

 

[Boduke]

One more thing. Is there trick to get the cotter pin out of the limiter? Or just fight it woth needle nose?

 

[Mattax]

With the clip out, the slot plate slide up and off the shaft.
Wait, the clip in your photo? That's a royal pain. I don't have great tip to make it easier. Needle nose pliers and sometimes a very small screwdriver to slip between the shaft and the clip.

If you want to adjust the timing from more initial, lets see what the number is on the plate, and tell us a bit more about what you're trying to do. With early emissions, Chrysler retarded the initial timing and made up for it off idle in the advance. Depending on what you're trying to do, and what's been done to the engine, often I think the best is to just shorten the slot on the inside (weld and file). Sometimes, an easier work around is to use manifold vacuum source for the vacuum advance.

There's a couple of example of welding up the inside of the advance slots. Lets see if I have enough internet here to find at least one.

 

[RustyRatRod]

I knew an old guy when I was a kid who owned a local carburetor and distributor shop. He had ALL kinds of now defunct and impossible to find tools. He had a tool for those clips. It looked similar to a pair of needle nose pliers, but had very small, blunt ends with a hole drilled in each end. It made quick work of those clips.

 

[Mattax]

Here's a show and tell post

360 Tune Up

If you have 7* initial on it, the off idle stumble is likely rooted in the lack of initital timing. Set initial at 12-16 and see if stumble gets better. Readjust the idle speed and idle mix screws before testing it out. More initial means less mechanical to keep total without vac advance in...

www.forabodiesonly.com

and maybe this helps too.

total timing reading accurate with no load?

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...

www.forabodiesonly.com

There's other guys here that also are very familiar with this stuff. Both Newbomb Turk and Halifaxhops have distributor machines which lets them do some off car stuff.

The heavy spring slows down the mechinical advance before 2000 rpm or so. This avoids having too much advance when the engine gets heat soaked. Drag racing is different. But drag racing the heavy spring is still and advantage because it can offset the retard at high rpm.

 

[Mattax]

I knew an old guy when I was a kid who owned a local carburetor and distributor shop. He had ALL kinds of now defunct and impossible to find tools. He had a tool for those clips. It looked similar to a pair of needle nose pliers, but had very small, blunt ends with a hole drilled in each end. It made quick work of those clips.

One day, when I'm really patient, that would be cool tool to make our of a cheap needle nose. Probably have to anneal the steel so it was a soft before trying to drill.