The Project Pad

Alright. Buddy that bought my old 4ktq wants EFI in a bad way. We discussed possibly just grabbing a 3b ECU, harness, and MAF, and throwing them onto the 20vt with a wideband and an adjustable FPR so we can tweak it in case things aren't quite right.

How logical does that sound? Besides the fact that the 3b will outflow the mc1 by leaps and bounds I don't really see a huge difference.

Mc? The timing is what I would be a little worried a out. If its an mc and not an mc2 than I bet it will run pretty well.

I've heard the spark needs are quite a bit different between 10 and 20v's but have no proof or anything. Really interested in this as well. If they aren't close enough I wonder what magic Marc could work on a 20v ECU to make it happen

RIP chip should be able to tune out the issues?

What about... 3B ecu and harness for fueling, and leave the MC1 ECU/harness for Ignition...?
Totally overkill and lots of wires. But could work, right? Shawn, you're doing the same but with MS. Should be doable.

Yeah that's all I'm doing at the moment. I don't know enough to tell you what to do about crank sensors though, because I think both ECU's would will need two VR signals from the flywheel. I know VR sensors are finicky so depending on whether you could just split/splice the signals it could be easy/hard to run it as a piggyback setup.

But at that point, honestly MS would probably worth it because then you can tune it and the majority of your build cost is going to be in fuel rail, injectors, AN fittings etc. From DIY Autotune a MS1 ECU kits are cheep cheep and to get a fuel only setup running piggyback is pretty cake, especially with your experience.

There was a car in the UK that was running it's 20vt on the 20vt Motronic. It's been a few years since I read about it, so I can't remember the name of the person/company...

vt10vt wrote:But at that point, honestly MS would probably worth it because then you can tune it and the majority of your build cost is going to be in fuel rail, injectors, AN fittings etc. From DIY Autotune a MS1 ECU kits are cheep cheep and to get a fuel only setup running piggyback is pretty cake, especially with your experience.

How does that even work, anyway? Would the MAC be too dumb to throw a shitfit if half of the sensors/switches were missing?

I guess a better question is, what criteria does the MAC use for timing control? The crank and cam sensors obviously, as well as the MAP sensor and knock sensor(s). Coolant temp? Air temp? Throttle position? (I know my Digifant controlled Golf extensively used ignition timing to control idle speed)

One of the things that makes me leery of the MC2 swap is that the fuel distributor has been sitting for a while and some of the bits and pieces are known plugged. When I do it it has to be done QUICKLY, like 10-12 hours work max. EFI would be loads easier because it's a known quantity and I have stacks of 460cc injectors, a 20v fuel rail, and a spare MS box that I can put in my other car to verify function before use...

It would be nice to compare a 3B timing map whith an MC timing map. However as a starting point I bet the MC would work just fine with a Stock 3b ecu with Stock 3b ignition timing map running 12 psi. The old school resistor mods on the MAC ECU would advance the timing alot.

Several people have done that conversion in Europe. Mostly German, but some Latvians too. There are many videos of 20vt Audis running Motronic on youtube. This website http://mtsonline.funpic.de/einfuehrung.html also has a list of parts needed for it. It's in German so use google translate. There's also a motorgeek thread of the motronic conversion: http://www7.motorgeek.com/viewtopic.php?p=338644.

Awesome. Thank you. I sent those links to my buddy. We're gonna start looking for the parts for all of it.

What about a 2.5l Eurovan setup? Should be easy enough to tune the old Digifart 1.2 for a turbo.

ur20v wrote:What about a 2.5l Eurovan setup? Should be easy enough to tune the old Digifart 1.2 for a turbo.

I've heard tell of this attempted years ago and they mentioned having fits making it work. Don't know/remember details though.....

Or how about the EEC-V from a 10-cylinder Ford van? Just don't use half of the outputs. If it's like just about every other engine from that timeframe, it just uses a 30-1 crank wheel and I-forget-what on the cam.

I know some people who have a supercharged B20 Civic. I was walking by their car in the paddock and did a double-take when I saw a Ford MAF in the intake tract... they'd converted the thing to run on Ford electronics!

I would think timing wouldnt be an issue. The 3b and AAN have higher compression ratios. vs the 20vt. If anything you might lose power unless you tuned it as stated above with a rip chip. I wouldnt go more than 20 degrees at 2 BAR

20? I thought they would detonate over about 7 degrees, and the retarded timing necessary for the crappy chamber + low compression + poor exhaust flow = exhaust valves losing their heads...

ehhh. At lower rpms with high boost you'll want that degree of timing. Its all about flame speed and fuel quality. Perhaps on a stock 20vt timing is that retarded. I would like to see a timing map from someone running stand-alone on a 20vt if possible