Camaro_Muncher

I am interested in the megasquirt conversion, is it a full dme replacement or just for fuel and accesories? Is there a write up anywhere on how to install it to a 944? I would like to use the MS-I with V3 board, Stimulator and maybe Megaview. I have a laptop for tuning. About how much would the setup cost? And what would i use for a harness? Can i use the stock one or do i have to totally fabricate a new harness? What are some opinions of the best setup for a '84?
Thanks

DanG

It can replace the DME completely. Fuel and spark.

There were some write ups on the background info, but they went offline a while ago. To my knowledge there's only 1-2 944 owners out there (non V8 hybrid guys) running Megasquirt.

MS-1, V3 PCB, stimulator for troubleshooting, and megaview are all good things. If you're only going to do one MS install, I'd suggest skipping the stimulator and just buying a pre-built MS from a vendor (RS Autosport is my favorite, the soldering is done by NASA certified technicians). Also, the MS View isn't 100% necessary. You can run your laptop to monitor everything, and wire up warning lights at a minimum, possibly even keep the stock temp/oil guages functional.

Setup costs depend on your choice of hardware and level of harness modification. Figure a minimum of $350, likely closer to $500 for the extra bells and whistles. You can hollow out an old stock DME box to tap into the stock harness or find a BMW E30 ECU for less money and hassle, it has the same connector. The harness itself will require a bit of modification, the biggest being the removal of the AFM and installing an intake air temp sensor in its place (likely with the now useless AFM wiring). The biggest wiring would be on a re-vamped ignition system, if you chose to upgrade the current design.

My question is why do you want to do the conversion? Not much to gain on a non-turbo unless you were going to be boosting or running nitrous. Otherwise, just grab one of those knock off chips on ebay and get an extra 500 rpm.

Rich Sandor

ask "theedge" His car is megasquirted. Do a search on the 951 forums.

Camaro_Muncher

I would like to get more engine manegement control and so i can troubleshoot problems easier. I thought it would cost closer to $200 and thought that was a good deal for what id get. Thanks for the info.

theedge

Its nickle and dime. Im in for probably under a grand including MegaSquirt, extra stuff for it, and all the wiring for a whole new wiring harness. Stock harness can be used just fine though, with the addition of some wires for an air intake temp sensor. Larger changes to things would require more wiring, ie coilpacks and such.

Remember that with more control theres more to go wrong And if you have doubts about your soldering skill you can buy preassembled units for $300-400 I think, then start from there.

To use the stock crank sensors, youll have to use the Extra code for now.

http://megasquirt.sourceforge.net/extra/

Go there to see what it can do, which is quite a bit.

One thing though, I still have to find out if the 944 N/A's 130 tooth start gear is going to cause issues. Basically no MegaSquirt can handle that number of teeth directly. What we can do for 944 Turbos is use a $1 chip to divide the pulses by 3, giving a "44 tooth" wheel to the MegaSquirt (or whatever other EMS). But 944 N/As use a 130 tooth wheel for some reason, which doesnt divide nearly as nicely. Ive started a thread asking about this on the MS forums.

If it causes issues, in theory you could swap the 944 Turbo start ring gear on there and youd be set assuming it fits Or see below.

Now, you can also use MS2 which is a different firmware code that runs on the MS2 processor. To use this you would HAVE to mount a trigger wheel on the front of the crank pulley to use, since it cant do 2nd Trigger (what our cars need, since they have two sensors). Currently MS2 can do missing wheel decoding (36-1, 60-2) but its only partly tested. Extra can also use these wheels just fine, so if the N/A starter gear cant work, and you dont want to swap in a Turbo starter gear or it cant fit, then mounting a trigger wheel on the front is the only option left.

And the other option is to use Fords EDIS system. This again requires a trigger wheel mounted on the front with a pickup sensor. AlexE uses EDIS and it works for him.

In short, there are tons of options and different ways to do things MS isnt intended to be a plug and play simple system but its extremely capable I think.

theedge

And MS wont do much for troubleshooting problems easier, itll be the other way around most of the time probably. The Motronic does what its supposed to do very well and you have a known base to start with when tracking down problems. However, youll learn LOTS about how engine management works, how engines work, tuning theory, etc while installing the MegaSquirt. If youre a tinkerer like me and want a good challenge its hard to beat the MegaSquirt.

Camaro_Muncher

im no doubt a tinkerer. I thought it it would be easier to troubleshoot problems like o2 sensor injectors etc. I might do this, but first interior then performance. Btw I have brown script seats, passenger is in 9/10 condition, but the drivers is a different story. What would be the best way to recover? Buy script material and give to upholstery shop? Or buy those 200 some doller ebay covers?

Rich Sandor

I've seen the rennbay ones in person on Lorne's burgundy interior 944, (local guy) and OMG they look like factory original. He said they were a bit of work to fit perfect, but now that they are on, I swear they look like factory seats. - not like the other fake seat covers that are obviously aftermarket!!

www.rennbay.com

theedge

Yeah itll help for that kind of stuff, simply because itll show it all on a laptop. You could use a multimeter and oscilliscope to figure those out on a Motronic, and those will be good things to have for the MegaSquirt. Ive used my USB Oscilliscope many times already