Hi everyone,

I'm wanting to purchase the Pertronix Ignitor kit for my 1977 F100 XLT Ranger, with a 351m on it.

Is there a reason why most sites show me compatibility with Ignitor, and the Ignitor II but not the III.

Any advice on what I should use would be great. And am I looking at a straight forward install and swapping the coil? or is a lot more involved and I'm missing something?

 

If I had to guess, I'd say it's because Pertronix does not even list the Ignitor III for any '77 Ford. And the big houses usually let the manufacturer add data and applications to their computer for them.
Likely this is due to your truck already having a Dura Spark electronic distributor and not needing a conversion. Very few would opt for it I would not think, unless they were having issues with the existing system.

However, in the actual catalog listings (if you ignore the automated part search) they don't differentiate. They just list some up to '74 and others to '76.
Very likely the earlier models could still be made to fit, but might be easier to just buy an earlier model replacement points style distributor. That way you get the new distributor bits and don't have any compatibility issues with the Ignitors.
At that point too, you could decide on any number of conversions, including ready to run electronic distributors. Albeit at a much higher cost.

Maybe some here have already fiddled with converting a Dura Spark distributor though, and can walk us through what might be needed.

Paul

 

Hmm, they don't even list the III for earlier vehicles, but in those even the II and I change numbers. They use a FO181 and 9FO181 for the '75 model year, and FO and 9FO182 for the '77 listings. Still no model III.
Makes a phone call seem even more reasonable.

Paul

 

Ok so I keep fiddling around with their finder and see that to get to a listing for the model III you have to go to the '74 model year. As soon as those listings pull up you can see some other inconsistencies that bear closer scruitineering.
For '72 they list all three, but only with the old numerical part numbers #1281, #91281 and #71281 for the I, II and III resepctively.
If you go to '74 however they show both the old and new (?) numbers of #1281 AND FO-181 for the model I, then #91281 AND FO-9181 for the II, and still just #71281 for the III. Which tells me (in theory) that at least the I and II fit the distributors up to '77.
Why they don't also list a different number and applications for the III, I can't answer.

So curiouser and curiouser, with answers just a phone call away...

Paul

 

You will need a new distributor. What are you trying to accomplish? Your truck already has electronic ignition and doesn't use points.

 

oh... said the noob.

I am trying to improve start up, idling and general acceleration.
Previous owner mentioned the last time he took the truck to a shop he was told that he needed to replace the rotor button soon. So this is combination of lack of experience, and hearing I should do an electric conversion while I'm at it. And thinking that that will also save some of my acceleration hesitation

 

 

Noone is tryn to put the "noob" down ! We just try to give the best advice based on our experiences and knowledge. Nobody wants anybody to end up throwing good money after bad.
I don't think they make one for D.S., Pertronix is designed to get rid of points and it screws down to the breaker plate and there is no breaker plate in a D.S. D.S. also uses a reluctor,wheel on top to make and break the current and the old points style has a cam on top to open the points, so another big difference there. The D.S. is a damn good unit that is far more reliable than Pertronics. Don't expect one to last all that long because anyone I know that has ever had one kept a spare in the glove box after the first time they were stuck on the side of the road somewhere. Maybe someone has had good luck with them out there but I have never really heard a good word about one. Don't forget they are pretty much a mail order piece, you won't find a replacement in any local parts store on any given day of the week that it decides to take a crap. Your just moving in the wrong direction here. I'd do what Base Camp mentioned if your dead set on getn rid of the D.S.and just replace the whole system with a "ready to run" unit. They just are not what their cracked up to be, for that matter other brands aren't any better.

 

I was just acknowledging my own ignorance

I really appreciate everyone's knowledge and advise.

My plan for now is to put in new cap and rotor, new plugs and wires and see how she runs as part of the routine maintenance.
I'll be diving in into those tune up.

 

Sounds like a plan. Nothing wrong with doing some digging and detectiving while you're messing around under the hood. Maybe a few checks here and there.
But sometimes things can be improved advancing the ignition timing. Which can be a whole 'nutha can-o-worms with these trucks. It's technically a piece of cake and can be done with basic tools. But after so many years our trucks tend to have distributors that are stuck but good in the block! Mine took a few weeks of soaking in penetrating oil and lots of cussing and grunting with various tools to get loose. But hey you can try and maybe yours is one of those that has remained movable after 40 years.

But as said, a basic tune-up and/or carb refurbishing can do wonders.
Good luck.

Paul