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Megasquirt EFI conversion

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This will probably take a year to complete, depends on if I meet & marry that rich super model, then I might write a check & have someone finish all my projects :-?

I'm still in the aquiring parts stage, have all physical car parts (318 intake manifold, bypass pipe & water neck) except the trigger wheel & sensor, GM weatherpak connectors, PVC wire,& megasquirt & stim board. I'm still undecided on ignition, seems the megasquirt gods are about to release hardware that would make coil on plug & sequential injection a much simpler task than it is now, & I have some crazy desire to do both. For now, I'll at least do EDIS, if nothing else, I can't see taking the time to install a megasquirt system & not take advantage of crank triggered ignition & ditching the distributor. The cam choice is still up in the air too, I have a nice close to 300 degree regrind cam, & some stock 264 cams too. I'm thinking turbo later after the megasquirt system is running good for 6 months. I may start with the 290 something regrind cam as N/A motor, then if I go turbo, I may go back to stock cam. With fuel at 4.09 for premium, I might use a 320i 1.8 ltr block I have. So a few options yet to be decided on.

Today I got my fuel sock extender made, PVC electrical conduit, cost 1.09 at hdwe store, cut the end off that's expanded to mate with another stick of conduit, walked next door to my neighbors guitar repair shop, borrowed the lathe & cut out just enough on the small end to make a tight fit. It is about 1" long. Now the gas guage will read empty when there is about 2 gallons in the tank, but I can draw gas all the way till empty. I will use MS 2, v 3.0 board, unless they release something newer before I buy.




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Will PVC hold up to gasoline?

no..it's only rated for air and water

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On the PVC part, I did test it buy letting it soak in a jar of gas on my back porch, I'd shake the jar every now & then, I just pulled it out & checked, fits just as tight as when I put it in there couple months ago. FWIW, I've had cheap white vinyl zip ties in the tank of my 528e for about 6 years holding a VW fuel pump in place, & they haven't failed either.

Update: Got my Wideband installed today, using JAW vers 1.03 bd, I built mine a little different, in that I thought the Fan for the regulator was a bad idea, so I used a cast metal case & a TO-3 version of the regulator mounted to the case with a mica insulator & transistor cover, ( for the non electronic geeks, that's a bigger transistor package for the regulator, transfer's heat better than a TO-220, the stock part) it only runs warm to the touch, without a fan. I just bought the boards & the micro, I had almost all the parts in my repair shop already, I had to order the LED display he spec'ed from futurelec, his main supplier, couldn't find it anywhere else. I've used them before, really competitive prices, but they ship slowly via mail from China or Asia, somewhere where it takes 2 to 3 weeks to get your parts.

I also used a 5 wire innovate 02 cable, instead of making my own 6 wire cable, to do this you have to measure the calibration resistor on the wideband sensor, then put that exact value as a resistor across 2 terminals inside the JAW box.

This let me install a 5 PIN DIN socket on my JAW box, so if I ever have problems with the cable or the sensor, I can easily plug in a new cable, or a new sensor troubleshoot. To run the cable, I punched out the small rubber plug under the speedo cable & drilled the hole out big enough for the DIN plug to push through.

My friend has my 60-2 trigger wheel & is cutting it to fit over the stock crank pulley, I still have to get a sensor for the wheel & fab up a holder for it. I will weld the sensor to the pulley instead of using JBweld.

I have decided to go with MS2 vers 3.0 board, according to Bruce on MSEFI.com, it may be DEC before the sequencer is out, & I'd only see small increase in fuel efficiency at low RPM's crusing with sequential injection, so my current plan is to swap the MS2 ECU into my 528e when the sequencer comes out, but I may wait to see if they make the sequencer module to use as a plugin addon to MS2, either way, MS2 should work fine.

For now I'm tuning my stock solex 2 barrel carb a little leaner, a wideband is interesting in that you get to see exactly how much leaner the car runs when you pull off the air filter. It was running about 12.4 to 12.6 at idle, & trying to squeeze better mileage out of the carb, so for now, bumped it up to about 13.2-13.4 at idle, just turned out the air screw. I'm surprised the wideband shows as high as 18 to 20 when you let off the gas at 2500 to 3000 RPM's for just a half a second or so. I also invested in a digital timing light that shows advance & will try to tweak my timing again after running a tank or two with the leaned out carb, trying to see what difference it makes on mileage. I spray painted one area of back of the crank pulley white & then put marks on there to make it easy to see from the drivers side of the engine bay on top. No more leaning over to see a little ball in the bellhousing, plus you know exactly how much advance at what RPM. I just set the motor to TDC, then sprayed the pulley, & reference that to a bolt on timing cover, I need to paint a line on the side of the cover. I can see my vac advance dist has about 25 to 30 degree total advance at about 2800 RPM. I want to know exactly what advance this tired old motor is running on with the dist, before installing MS2. I will run just ignition 1st, tune that, then after it runs good on ignition for weeks or months, install the 318i manifold & all the fuel bits. I'm probably going to run stock 318 injectors, at least at first for this tired old motor, but send them out to get rebuilt/cleaned/tested for $16 each, I need to do that to my 528e anyway, so I'll send em all at once.

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