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

  • irkli@lemmy.worldOPEnglish
    2·
    1 year ago

    OK I rummaged around in search engine and RockAuto.com and found some cheap, common Toyota coil on plug modules for which I can get connectors too. And bought one. The issue is (see photos) this is an old pushrod OHV motor, cam in block, and all COPs are designed to fit down through the valve cover etc. So it dangles. This is a really small car, and even if I make brackets to support them, it’s bust. I’m not relocating the battery (umm low center of gravity was not ever considered…) so this scheme won’t work.

    I think coil-near-plug as a smart Volvo fan suggested is the next thing to look at; I’d ordered this part before that post. I’ll post on that when I find one to examine.

    In the mean time here are photos of failure, lol. Projects like this are failure every step of the way through success.

    Plug side of the motor. It’s a very small car, same wheelbase as a Yaris (within 5mm). Tiny engine compartment especially for 1960.

    Plug side of the motor, stock form

    COP on plug #2. Immediately obvious to me not gonna work. Simply too tall. Cyls 1, 2, 3 maybe, but 4, 5, 6 are under the battery and I’m not moving that (again). Too cluttery.

    Yeah, no, not good. Coil mass too far from block.

    Lifted by hand to in-line with the plug.

    I'd fab a bracket to place it about here....

    Here’s the module itself. Lovely thing! Coil and MOSFET driver right in the sealed unit. I lurv this new shit.

    Heres' the candidate Toyota COP module.

    • AttackBunny@lemmy.worldEnglish
      1·
      1 year ago

      Why not just use something like the MSD conversion COP setup? Basically you remote mount the coils and then make wires to the correct length. Iirc the kit even has then ignition control box and distributor

      https://www.motortrend.com/uploads/sites/21/2019/12/18-msd-holley-coil-on-plug-small-block-chevy.jpg?interpolation=lanczos-none&fit=around|660:440

      Also, not sure about Toyota but on most Nissans I’ve seen, with coil on plug, the boots come off, so you could theoretically do the same thing as the MSD with the coil packs you have if you remove the boots and then remote mount.

      • irkli@lemmy.worldOPEnglish
        1·
        1 year ago

        I’d rather not use Holley/MSD stuff. It’s aimed at the high-horsepower, GM V8 scene, grossly oversized for my 125 hp engine. I find Holley’s tech not all that well made, and definitely not OEM quality (though OEM quality is highly variable… and aftermarket replacement parts can be sketchy). Those are $100 per coil, and I need six. The stuff is physically huge. And if one fails, they have to be ordered from Holley or Summit or something. I’m making 20 hp/cylinder and it can’t possibly rev past 4500 rpm.

        The last part will get me flamed but tough shit: Holley’s support forum for their EFI is admin’ed by a guy I had to battle to even sign up to. Bible quotes on every reply. Shitty and officious and incorrect technical advice.

        But it’s also more interesting to work out properly-scaled OEM stuff I can adapt from junkyard sources.

        I will go look at Nissan too, thanks for the hint! A coil-near setup will be tolerant of some lead length too, I kinda don’t want to “research” subtle coil behaviours that result in failure “later”!

        • AttackBunny@lemmy.worldEnglish
          2·
          1 year ago

          Fair. I hate holly too.

          Look specifically at the B15 Sentra (QR25DE engine)coil packs. With the boot off there is maybe an inch/inch and a half protruding from the bottom IIRC. That would be 2002-2006 iirc.

            • AttackBunny@lemmy.worldEnglish
              2·
              1 year ago

              I can’t find a good picture of them but this is the dealership parts departments image to search from.

              If you look at the pic you posted, the boot comes off at the flared rubber part. Inside there’s a spring, which makes the connection from the coil pack body to the end of the boot. The part that sticks out of the bottom on the coil pack is just enough for the boot to snap over. Idk if it’ll be exactly what you’re looking for, but that’s one of the more low profile I’ve seen (not overall, just on the “business end”.

              The boot and spring looks like this loose

              • irkli@lemmy.worldOPEnglish
                3·
                1 year ago

                YES! Thanks!! Wow, the devil’s in the details… They “all look like that” but on the few I’ve seen, the long snout is cast plastic and not removable. That makes a huge difference. Thanks so much for the detail!

                Gonna get to an LKQ (junkyard) next week and try to find one for a look-see. Nothing like having a thing in your grubby hands for gathering information.

                Seriously, I can’t thank you enough. This is great info.

                • AttackBunny@lemmy.worldEnglish
                  1·
                  1 year ago

                  You’ll probably be hard pressed to find a B15 Sentra with a QR25 in it. It was only available in the SER and Spec V. BUT the 4 cylinder Altima (iirc 2001-2006) SHOULD have the same coil pack (same engine, different tune)

                  Failing that, look at LS1 coils.

                  And no problem. I literally do what you’re doing for a living. Mostly.

                  • irkli@lemmy.worldOPEnglish
                    1·
                    1 year ago

                    Ok cool explains the diffs re: rockAuto. Or they have afu listings, hardly the first time… I’ll hunt those down.

                    What do you do for work? If I did this, I probably wouldn’t do it for fun! Lol.

                    I like doing work from first principles. Luckily since I basically have no choice. Electronics and software was my living, once. .