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Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Sat Mar 02, 2019 8:22 pm
by Huer
Not even necessary. I took the cap off and saw just how simple it is. 2 cycles per revolution. 50% duty cycle. Yup, 1 half closed, 1 half open. Makes it kind of easy. Now this engine also has secondary valves for the long runners that open with electrically modulated vacuum servos. This engine also seems to have either a knock sensor or crank position sensor. I can't believe how overbuilt that thing is! I'm taking the top of the motor apart and I'm thinking - What did they have in mind for this thing???

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Sun Mar 03, 2019 11:09 am
by Fred
Okay, but isn't it a 6 cylinder? Hopefully there's another sync point, but I can already say there is no canned decoder that will do a good job of that, so I'll have to whip you up a new one, and send you S19s to try until you get a result. And, that's assuming there IS a second sensor, as that's useless on a 6 without one and mediocre on a 6 even with one.

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Tue Mar 05, 2019 7:55 pm
by Huer
There is what looks like a crank sensor. I don't have that motor apart in that area just yet. It's still really cold in the shed, so I find ways to procrastinate. There are also secondary valves in the intake that should open like the secondaries of a carburetor, or at high rpm, I can't say for sure. How do I get one of those Jaguar boards?

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Mon Mar 11, 2019 9:00 am
by Fred
Before you get carried away with buying boards/boxes/etc, let's establish the viability of the engine as a candidate to run on FreeEMS by establishing the full pattern and the timing relationship between the two. Best done empirically with some kind of scope or logic analyser using the starter with plugs out, but can also be done with LEDs and a spanner IF optical/hall, but not if VR. VR requires speed to function at all.

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Mon Mar 11, 2019 2:08 pm
by Huer
Both crank and cam sensors are hall effect. I can't turn the engine while it's on the stand, the arms touch the flywheel. So I have to make that running stand before I can do anything.. All my steel is still buried in snow. It may be a week or so before I can continue. I have some other projects to do too. I am ordering a couple encoders to play with. I want to make a cruise control that I can set by means of an encoder. I haven't looked for this in the code yet, but does FreeEms have a abstraction and function for a Vss?
I rediscovered Jameco. I used to have a subscription to their catalog back in the late 90's, but I forgot about them over time I guess. I was poking around looking for a way to have your motorola MCU plug into a socket so I could break it out and use it without having to do surface soldering, which scares me. Anyway, Jameco popped up and I started looking through all the cool stuff they have and had a shopping spree :P They have MC68HC11's, but you are talking about the HC12, right? Those are like $30-$50 and surface solder only (From Jameco anyway). Is there a PLCC version somewhere? Or can I get away with using an HC11 for your code?

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Tue Mar 12, 2019 10:05 am
by Fred
If you're planning to remove the flywheel, then that works, just turn it by the pulley, unless one of the sensors is ON the flywheel? In any case, don't commit to the hardware until you know it's viable.

VSS: Yep, but only on a branch that Rob and I have been working on over drinks in the evening from time to time. Not ready for prime time. Not sure what you are on about with respect encoder, but cruise is best done with just VSS and DBW and a set/forget arrangement.

There are socket thingies for this device, but they're really expensive. Looked into that for initial programming of them. Decided against it.

Nope, only one MCU works with this code, and only one or two or three other very similar ones *might* work with it with some changes. Has to be HCS12XDP512 for now.

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Fri Mar 22, 2019 6:12 am
by Huer
This thread isn't dead. Now that the snow is melting, I have been pretty busy with the Mustang. My wife insisted that the be taken to a shop to have the motor we built dropped in. This jerks ripped us off really hard. They overcharged by a magnitude factor of 3, and to add insult to injury- we had them do this as to have it done without damaging anything, right? So I just found this out last week (several months after getting the car back) They had taken a hammer to the drivers side, bran new, chrome, tri-y header to clear the steering gearbox which it was flatly laying on. A phonecall would have been nice. If they wanted to smash up a header I could have brought them the old rusty one that actually cleared. Anyway. So I had to rebuild and shaft down the casing of that gearbox. As far as the header.. well.. It gets to stay dented up for now until I put in a rack conversion and Then I'll buy a new header *grumbles profanely*
So about the Yamaha motor. The engine stand is frozen to the floor still. It is immobile. Another couple of 50 degree days will fix that and I will get it on a mount stand at least. Then I can look at the flywheel. And I can throw some code together to make a hall analyzer and see what the pattern arrangement is between the two hall sensors for the crank and cam and draw up an encoder pattern. I'm sure it's quadrature of some deviation. Then it should be easy to mod up the freeems code to work. About that Jaguar board.. Hey Fred! lol

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Fri Mar 22, 2019 12:05 pm
by Fred
Bummer. That's why I always DIY. Everything. :-)

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Fri Mar 22, 2019 2:53 pm
by Huer
Now, you see, I WOULD have done that. Because that's the way I am also. But not her. Lol. She's had the car for a long time, and has always really wanted to fully restore it. Before she saw the evil ways of men who work on cars for a living, she had fanatical ideas about the things they did, you know, like not being heinous scam lords. We wasted almost 3 years with these people. And now she understands.

Re: 1976 MG Midget meets 1994 Taurus/Yamaha SHO

Posted: Sat Mar 23, 2019 12:32 pm
by Fred
Lessons learned the hard way are not quickly forgotten. I've learned my share through that route :-D