924Board.org

[rx924]

Okay so here is the deal i'm on a mission to do the megasquirt EFI swap in my 1982 924. I'm planning on getting MS2 v3.0.

But first off I would like to get the ignition system on the car first. I've been doing some research and understand that you need to attach the trigger wheel (36-1) and a hall sensor to the crank for the EDIS 4 to work.

My problem is that I would much rather the trigger wheel on the camshaft. I know I could have a machine shop make me a 72-2 wheel and the EDIS 4 wouldn't know a difference.

What I want to do is put and EDIS 8 on my car with a 36-1 trigger wheel on the camshaft. Since the EDIS 8 fires a pair of cylinders every 90 degrees i should be able to disconnect one spark plug from each pair and be able to fire each of my own cylinders per 90 degrees rotation on the camshaft.

Would this work? and will the MS2 be able to interpret my way of using the cam for crank position instead of using the crank for crank position?

Thank you very much.

[Min]

[rx924]

[Min]

[Andrew NZ]

What's this "rx924" thing.....there is only one real RX924 in the world
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Andrew
1977 RX924 race car
12a bridgeport supercharged
www.race4-dcup.co.nz

[rx924]

[fiat22turbo]

Here's my solution using the trigger wheel from the group buy that we did here a while ago:

Group buy trigger wheel mount compared to the one I built:



Original Group buy trigger wheel setup (made to clear cars with A/C, etc):



Building the VR Sensor pickup mounting plate, pattern made with scrap cardboard and transferred to the aluminum:



VR Sensor mount built using hardware store aluminum bits, aluminum solder, MAPP torch, vise, a hacksaw, a drill and a tape measure:





I've seen other VR sensors mounted closer to the engine attached to the oil pump/FMS housing, next to the timing belt cover. With the trigger wheel mounted behind the main pulley (with some washers behind the water pump pulley, etc) you can find some very thin trigger wheels online that work great for that kind of solution.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[rx924]

[fiat22turbo]

It was someone's car here on the board.

Wasn't much to it. Basically a piece that bridged the two 10mm bolts with a ring of aluminum to hold the VR Sensor in place. A set screw what put into the outer edge of the ring to hold the sensor and to allow for fine adjustment of the sensor spacing (1-2mm gap preferred).

I would order yourself a trigger wheel and then go out to the car, pull the pulleys off and hold the wheel in place while you hold the VR sensor in place and then build the design around that.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[rx924]

[rx924]

OHHHHHH.

Huge question here where do you guys recommend buying parts. I was thinking about buying almost everything off DIY autotune. Any other good sites?

[fiat22turbo]

DIY is pretty much the best place to go, IMO.

Use whatever sensors you'd like, you can tailor the MegaSquirt software to suit. I used Chrysler sensors and injectors because I have stacks of them around and I know how well they work.

Pulled the coolant temperature sensor housing off the back of the head. Left the stock gauge sender hole alone and drilled the other one out and tapped it with the proper pipe thread to hold the Bosch Coolant sensor. Put the gauge sender back in place along with the new CTS and all was well.

I used EasyTherm to dial-in my sensors based on info gleaned from the net and backed up by my own measurements. The GM-spec sensors work right out of the box, but that is a very minor issue compared to the problems many find with their first few starts

I use the MSExtra code to control the fuel and the EDIS (I've got an MS1 v.2.2 board) with the proper mods to control the EDIS ignition module.

MegaSquirt is mounted to the map pocket/shelf under the passenger side of the dash, under the glove box. Used DIY's wiring solution. The labeling was very helpful while lying under the dash staring up at it all.

Replaced the stock fuel pump relay with one recommended by the MegaManual for the task. Had to move a couple of wires on the relay mount. Made use of the empty Relay sockets to fit the other relays needed.

EDIS ignition module is mounted to the top of the driver's frame rail just in front of the brace for the strut tower. Fit just about perfectly there.

Mounted the Escort EDIS coil pack with the stock mounting bracket to the passenger frame rail behind the heandlight (I don't have pop-ups, so I have room in that area) used stock Escort plug wires. Out of the way and the plug wires fit nicely.

Some Ford/Chrysler/Mitsubishi 4-cylinder fuel rails are the proper spacing (approximately 95mm center to center). Hunt around for a few to find the one that will be easiest for you to mount. Remember you want the rail to fit securely, leaks are very bad, mmmkay?

Injector inserts are expensive, (034motorsports.com) unless you're a machinist or know one that can cut 24mm threaded bits down and bore the proper holes in them to hold the injectors (they have to be smooth or you could tear the O-rings). Some have bored out the injector holes in the head to fit the injectors lower into the head to gain room for the rail, etc. as another possible option.

There is a How-to for fitting a TPS to the throttle body over in the How-To section. I think some VW's or Audi's used a throttle body with a TPS that can fit, but I don't know which ones off-hand.

Buy the TunerStudio software. Seriously. It is worth every penny and is just getting better and better.

Good luck!
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[Min]

DIYAutotune is the place to go, I have purchased quite a few megasquirts from them now.

Buy the wiring harness as fiat22turbo mentioned, well worth it. Makes things alot easier, I will be purchasing one and redoing the harness on my 924 (have used those harnesses on a handful of other cars now).

Min
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Custom means it didn't come from a box.
1980 n/a with EDIS and Megasquirt II Injection. 7 different colors and counting.

[Raceboy]

Of course you can use EDIS-8 on 924, you just have to twin-plug the head. Which would btw be quite desired upgrade on 931 for example (reduces the MBT by 10 degrees at least).
_________________
'83 924 2.6 16v Turbo, 470hp
'67 911 2.4S hotrod
'90 944 S2 Cabriolet
'78 924 Carrera GT replica
'84 928 S, sold
'91 944 S2, sold
'82 924S/931 "Gulf", sold
'84 924, turbocharged, sold.
http://www.facebook.com/vemsporsche

[RC]

A twin plug head would be ideal, and the only reason to consider EDIS 8. Unless you have already invested your money and emotions on EDIS hardware like the other guys, there is IMHO no reason to consider EDIS at all. It is outdated technology and WILL complicate the installation, tuning and reliability factor. MS2 running the extra code is capable of decoding virtually all toothed wheels available directly, processing the signal and driving whatever coil(s) you fit, including EDIS coil packs if you chose.

I disagree with the nay-sayers above in that it is not only possible to run a cam wheel but has distinct advantages. Also it is just as easy or difficult to tune as a crank wheel. Easier in fact if you ever wish to run sequential ignition/ injection/ COP/ CNP, which WILL require a cam sensor of some type even if a crank wheel is installed. Less hassle & drama than correctly setting up a MS with EDIS hardware too.

Since I`m running a supercharger drive pulley, in addition to a multirib belt accessory drive off the crank, fitting the trigger wheel there isn`t an ideal proposition. I`m also able to run a 4 x LS2 CNP sequential ignition. This particular 36-1 wheel is a $20 Ford part, modified & fitted before I even purchased my lathe, so its not difficult for anyone to do either. Sensor is a GM/ Saab part selected solely on physical dimensions & price. there`s nothing special about pickups. Easier still now that DIY make and sell the wheels.







Few more pix here: http://s183.photobucket.com/albums/x187/RC924/Ignition/?start=all

Personally would suggest doing some more reading & research, particularly on the MS sites/ forum and planning things out before rushing out and buying stuff.
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World`s quickest 924 2L slushbox