converted to electronic ignition tonight

[maytag]

Hey all!

So I pulled the stock electronic ignition pieces off the parts car this evening and swapped 'em over to my '76. I wasn't trying to fix anything.... but my wife's been after me to either use 'em (the parts-car parts), sell 'em or throw 'em away! And this was one I wanted to try because most folks seem to agree they're more reliable.

The vacuum advance diaphragm is bad. no surprise. But I remembered reading others are using this setup but not running the vacuum advance, so I figured I'd try it out! WTH, right?

It seems to run more smoothly, but it DEFINITELY needs the advance. I set it at about 15 degrees (idling at 800 rpm, hot) but it needs more on top.

So I'll be looking for a replacement advance unit.
Are there options other than stock that I should consider? Does anyone make an adjustable unit, so I can dial-in the amount of advance I get when it's all in?

Any help and / or suggestions will be appreciated.

[manoa matt]

I don't know of an adjustable unit that will fit/work, the stock ones are even getting hard to find. A while ago you had a choice, either 10 or 14 deg of vac advace depending on US or California models.

There are two versions of the 79-85 electronic distributors. Some have 22 deg advance(11 at the dizzy) and some have 28 deg advance (14 at the dizzy) To find out remove the cap and rotor, push the weights out of the way and look for a stamped number below one of the weights, it will say 11 or 14.

One unit was for the Carbed 79-80 cars, while the other unit was for Fi 80-85 cars. Sorry I don't know which ones were installed on which cars.

[Luddite]

I would be truly impressed if my wife knew my inventory of parts that well...

[So Cal Mark]

the replacement vacuum units that are available now aren't very good, and pricey. They seem to last less than a year and cost at least $60. I don't know where they're being made, but the rubber just doesn't hold up to the heat from the manifold at all

[mdrburchette]

The vacuum advance unit isn't going to address your problem. It only helps aid in advance in low rpms when you have more vacuum. It's not going to cause additional advance at WOT. You can have your distributor reworked with heavier weights and different springs. There's a fella in MA that does this for our Marelli distributors.

[maytag]

The vacuum advance unit isn't going to address your problem. It only helps aid in advance in low rpms when you have more vacuum. It's not going to cause additional advance at WOT. You can have your distributor reworked with heavier weights and different springs. There's a fella in MA that does this for our Marelli distributors.

As I was laying in bed last night, it occurred to me that I'd confused the issue with my terminology "on top"... I only mean that it needs more advance at the top of the curve. I can still build power to 7K, but it doesn't have the crispness off idle, or at part throttle that I'd like.
I'll try to find the advance unit first, but I'd be interested in your guys' contact info, for a "maybe later".

Thanks to everyone else for their helpful posts.

[skumandeth]

this is something I've been curious on because my '75 had been converted before I bought it. It has no vaccuum advance doesn't look like it ever did but, I'd like a little better giddy in the low rpm's, It's kinda doggy till 3200 then it really starts taking off, but I was considering lighter springs from a gm dist. The parts car I have is same year with points, is there a way to use that vac advance, or am I stuck with playing with the centrifugal?

[manoa matt]

"I would be truly impressed if my wife knew my inventory of parts that well..." Yes, me too, I'd be impressed if she even showed an interest.

Maytag, 7200rpms is about the limit to take a fiat motor with stock cast pistons. If you want to go above that you should have a very well balanced rotating assembily and forged pistons. The other thing is the advance plate gets gummed up and the distributor and advance weights do not want to "snap back" If you take the cap off and twist the rotor and advance plate it should move, but snap back to its original position. You may think the springs are worn, but the shaft is usually gummed up. You can free it up without removing it. Spray some PB blaster at the interface and work it back and forth for a while until it frees up.

Skumandeth: "It's kinda doggy till 3200 then it really starts taking off" I think that is the secondary throttle opening up on the carb.

[maytag]

okay, well, I haven't looked since I posted the last, because I can't seem to get away from the office when there's still daylight
Maybe someone can enlighten me:
the stock electronic unit with the vacuum advance has a centrifugal advance mechanism as well, right? ie: springs & weights? Can I steal & rob springs & weights off the points unit to get my curves back the way I liked 'em?

OR: MDRBURCHETTE: can you send me some contact info for your guy in MA that does the re-work for ya?

please?

[mdrburchette]

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