Here is a photo i just took.

MY distributor doesn't seem to have a module, is that normal for a vac advance dizzy? I paid $100 for carb/intake/dizzy combo.

 

I had one that looked like that. It's set up for a race car. The vaccum advance and ignition module are removed because it's only used as a magnetic pickup. The plug on those wires is designed to plug into an aftermarket ignition such as a MSD box. Mine was set up exactly the same except I also remove the weights and springs and welded the shaft in place. I didn't want any kind of spark curve. My distributor was locked and installed at full advance. My new MSD distributor is set up the same way but I didn't have to modify it to do the same thing.

I wouldn't recommend using it like that on the street. That's just a typical large cap distributor. Nothing special about it. You could leave the wires like that to use an aftermarket ignition but reconnect the vaccum advance. You need it for part throttle operation on the street. Depending how the weights and springs are set up, you'll never know exactly what the spark curve is doing unless you have that but on a distributor machine.

Took another look at that picture. I can't tell but it looks like the vaccum advance is still hooked up.

 

So can i buy a ignition module and make it street worthy again?

Vac advance uses 4 pin modules right?

Can i just reconnect it and be on my way?

 

You'd need a module, condenser, wiring harness, mounting screws and possibly a new pickup coil. Nothing that can't be done, but it might be easier to just get another distributor.

 

Old large cap HEI distributors are dime-a-dozen. You can go to any junkyard and pull one from any 1974 to mid to late 80's car or truck and drop it in. I'm not saying they're all going to be 100%. I've seen a lot with worn out shafts or weights but it might be easier to just find another one than try to put that one back together.

 

that sucks, cause all the junkyards are a drive away, and i dont have a car to get there.

 

that sucks, cause all the junkyards are a drive away, and i dont have a car to get there.

Wondering how cheap it would be to repair this dizzy.
Its in great condition. The magnetic pickup is still in working condition. The bushing and all are still very tight, its a very un used dizzy.

 

Why ???

-- Joe

 

A race car doesn't need a spark curve. A timing curve should be at full advance before 3000 rpm. I launch at 4500 rpm. It's just one more variable to eliminate.

 

Well we all dial it in before 3k, but normally a little bump after peak torque to compensate with dropping cylinder pressure is in order. Especially if your reving the motor to 7k (race motor, right?) than I'd imagine your peak is around 5k or so, so i'd be adding some advance in and scaling it up.

I see your point about launching at 4500 rpm, but where's the peak torque on your motor?

--Joe

 

Peak torque is 4500 and I go through the traps at around 7000. The converter stalls at 5700.

The ignition has a start retard so the timing is dropped back up to 20* to crank it over. Above 500 rpm and it goes to full advance. I don't normally need it. I can crank the engine over before turning on the ignition.

A factory unmodified ignition may not be at full mechanical advance until over 4000 rpm. Vaccum advance is something different and can add even more but it's for part throttle operation.

 

I put up a post in the parts wanted forum . Another meber came up with one fast and cheep .

 

That distributor has been gutted for use with an MSD ignition amplifier box. I'd recognize those pink and green wires anywhere. That's why no module. The pink & green wires would go to the magnetic pickup inputs on an MSD box.

It looks like a hack-job to me. Moroso centrifugal advance setup, electrical tape, rusted all to heck, Crane vacuum advance lockout cam and vacuum advance unit. Yeech. Disgusting. Looks like something I would use.

 

That's an adjustable vacuum advance can, not a stock one. Of course it's probably rusted to hell inside anyway.