this post was submitted on 20 Jul 2023
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In another post on this community, partially just trying to generate a conversation, i asked about adaptable coil-on-plug modules. A couple folks were helpful, but it's still thin on the ground here, that's cool, it's all new, etc. Here it is: https://lemmy.world/post/1263808 (not much).

But I'm serious about designing and building a new ignition system for this ancient, forgotten engine that I'm kinda expert on by now (that expertise plus five bucks buys me coffee at starbucks). I've got two cars with this engine now, it's just barely tenable to drive now, parts are extremely scarce (eg. timing chain setups).

Anyway this engine, the Rambler 195.6 cubic inch inline 6, has roots back to the 1940's, AMC slapped a shitty OHV head on the old flathead engine, introduced a number of reliability problems, then solved those just as they introduced the brand new design engine, the 199/232/258.

It's got a once-conventional distributor, contact points and coil ignition. There's a Pertronix in there now. It works fine, but I hate them -- the distributor has to crank two rotations before it fires the coil, so the engine cranks for over a second each time, instead of firing right up on the first contact-point opening. I WANT THAT BACK.

So I'm gonna make new electronic guts for the distrib, drive some form of coil-on-plug, and do software spark control in the computer I've got already running the electronic carburetor.

ITT is chat about research, photos, etc. I'll make a web page for the project like I usually do. My Rambler Lore website is https://www.ramblerlore.com/index.html

Here's the page on this engine: https://www.ramblerlore.com/AMC/195.6ohv/index.html

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[–] irkli@lemmy.world 2 points 1 year ago* (last edited 1 year ago)

Last post today: the distributor (no photos yet) is a typical old Delco Remy, they're OK, but all of them are worn out after 60 years, shafts wobble, etc, and new ones don't exist and no one rebuilds them any more (I do my own).

The plan is to replace the distributor guys with an optical coder that gives absolute position so the first cylinder fire position reached actually generates a spark -- [EDIT:] 60 degrees of crankshaft rotation, not 720 etc. Pertronix II needs a full rev to determine angle and another I think to work out coil dwell.

I use MegaJolt/e with EDIS-6 on one of these engines in my sports car, but that stuff is old now, I dislike the single-source Megajolt now, 10 years later. With COP it;s just some logic drivers, sensors, and a spark map. I'm running two fuel maps now for the carb (AFR and enleanment feedback) so spark will be easy.

Here's a distributor stripped to the housing, shaft, and drive gear. The mechanical advance was stripped out of this one, but for fail-back purposes the one that goes in the car will have the advance junk retained, just pinned to disable, so in theory the contact points could go back in.