Megasquirt begins

[boxdogracing]

I'am starting to build a Megasquirt system for my 83 spider. I purchased a Megasquirt II V3 kit as well as a Jim stim kit and USB adapter from: http://www.diyautotune.com/catalog/mega ... -c-30.html

I started by assembling the Jim stim kit, very straight forward with easy to follow instructions. Then began the MS II V3 board, got as far as step 22. This step deals with you're choice of IAC and ignition components, after 2-3 hours of research I realized there was going to be more to this than I had thought.

After many more hours of research I have a better idea of what I have got my self into. First I have decided to ditch my MSD box, and for simplicity I'am going to use a GM 7pin HEI module combined with the MS II for ignition control (I plan to go coil on plug later). I have also found little information on the Bosh IAC control, however the GM IAC has been used by many others, so setup info is easy to find. I found a Jeep 4.0 uses a GM style IAC with a housing that can easily be modded for this type of install, so that will probably be the best solution for me. The change of these components also means once I start to hack up the OE wiring harness, there will be no going back. So I'am no longer looking to install the MS in the L-jet box as I had originally planed. I'll build in the MS II box and splice into my harness. I did happen to find a Cadillac Catera uses a Bosh throttle position sensor with a D shaped shaft that I think can be made to fit, this sensor is not needed but would help in tuning if made to work.

Now over a week after I started I'am ready to continue with the build, however work and other commitments mean it'll have to wait a little more. I'll get back to it when time allows, and keep you posted.

[pastaroni34]

No no, don't wait. Stay up all night with your soldering iron. Its not like you'll actually be able to sleep while you're thinking about your 'squirted Fiat

Glad to hear your project is rolling along!

[ClarkTheShark]

you do not have to use the IAC setup. the standard bosch aux air works fine. all you have to is wire one lead to ground, and one lead to the fuel pump relay... that way it only comes on when the car is running. here is some pic of the completed install. i went with EDIS rather than HEI. although im sure its all about the same. also, go ahead and buy a relay board. i made my relay cable out of 3 strands of cat5 network cable. saved a bunch of money.

[ClarkTheShark]

o and btw... if you want any kind of throttle response with the speed-density algorithm, you will need a throttle position sensor. i got mine off of a nissan 240 or 280z. like jason said it will run just fine under steady-state conditions. but when you punch the throttle, it will bog down. there is alot of little things you will eventually want to get setup, 1. wire your cooling fan to have MS control its operation. 2. adjustable fuel pressure regulator 3. wideband 02 sensor (crucial) 4. exhaust gas temp sensor

[boxdogracing]

Clark how would you're IAC setup control idle speed. It would seem to me just powering it open would have the same effect as adjusting the throttle stop. The way I plan to set up the GM IAC the Megasquirt should hold a constant idle speed regardless of temp, elevation ect., automatic adjustments on the fly. I think I should be able to use the OE relays as my spider was factory EFI. Obviously I'am only in the planing stage and still don't fully know what its going to take to complete.

I do already have an adjustable fuel pressure regulator and an Innovate wide band already installed and operational. Right now I have my fan controlled by a GM coolant temp sensor and a MSD smart switch. Rock solid control for now, but plan to use Megasquirt when ready. Additional ideas always welcome.

[Zmatt]

This is awesome. I hope MS gets more traction in the community. It looks like a great way to make our cars more reliable and enjoyable.

[So Cal Mark]

Clark, nice pics of your engine setup, but why draw air directly above the exhaust? That hot air has to be costing some hp

[ClarkTheShark]

yea mark ive tried to figure a way to route the intake better. but without cutting a giant hole in the engine bay i dont think its possible. i used exhaust wraps which made the headers much cooler. i get IAT's of about 92f on a 70f day. this is basically my street car anyways. The next fiat i build im not going to even mess with the lampredi 2l... great engine, great soul, great sound.... but i want vvt/vtec and a little more technology in my next build. considering buying a wrecked honda s2000 and go against every cell in my body to baster-size a fiat by putting a japanese engine in it...

[Daniel]

honda s2000 and go against every cell in my body to baster-size a fiat by putting a japanese engine in it...

this had been done already in a 131 ! sounds great at 9k to

[racydave]

I don't have any squirt experience, but got the jolt dialed in. You guys that got the balls for all this, have my respect for sure. What I do have is a stock engine, with headers, and a bad 36 ADL. After riding in a bosch 82 for 5 hours recently, Im prouder of my simple set up. A couple of ideas I have are like this. Make a dedicated harness without splices . A interupted connection can only cause you grief later. I try to run a wire without unnecessary interuptions. Improve your skills here, its the life, and reliability of your project. Sheathed 18 and 20 gauge multi wire cables are boss! Top dollar tools such as proper crimpers are a must also. Be carefull they dont crimp to tight, and cause the wire to break also, as the crimpers are adjustable, and I found this by experience. Second, I do not know how you would tune anything by lap top without a like minded friend to either drive or punch the numbers. Mine is simple enough to use the vacuum sensor as opposed to the TPS. If you have vacuum issues at idle with wild cams, its not an option, but theoretically the vacuum is a better load sensor. I wanted to do coil overs, but the technology was not there yet, so the EDIS worked good for me, but mounting it on the drivers side, away from the heat was my option, and I used stock Escort plug wires, it was easy. . Anyone that looked at my MAP for a base, and has higher compression, should dial down the max timing for sure! Would it be easier to just use the jolt with the squirt? Shoot for simplicity to start, and make good wiring choices. Squirt alot, and jolt when you can! Anyone can make a drag car, but overall streetability is what counts. Two gauges I would like to add, for scientific back up are the air-fuel ratio gauge, http://www.autoanything.com/gauges/65A4 ... kc=YSSPPRO, and a good head temp gauge so I do not cook the engine.

[FiatMac]

It is good to see Megasquirt getting some traction here in the Fiat community. I got interested in this system back in 2003 and purchased a Megasquirt I kit under the second group buy done by the developers Bowling and Grippo. Putting kids through school and other life events resulted in putting the project on the back burner until recently. I have upgraded the ECU to Megasquirt II and will be controlling both fuel and ignition. Ignition will be EDIS. I bought an aluminum front pulley with trigger wheel and a pickup from Jason Miller (millersmule).

I was going to wait to install this with my performance engine build, but I now think that I will install it with the current stock engine to get experience and see what improvement it makes over the stock system.

The introduction of the Tuner Studio tuning software should make tuning much easier.

There is also a load bearing dyno shop, Six Sigma Dyno Services,http://www.sixsigmadyno.com/ located about 20 miles from me that does dyno tuning of engine management systems. Megasquirt is one of the engine management systems that they work with.

It will be good to bounce ideas off others.

[burgandy81]

I am just getting my squirted spider on the road. My project is also extremely slow due to other commitments.

81 Spider, MS2, Millers Mule EDIS (with COP conversion), Lancia intake, DSM injectors, new wiring harness (kit). Work was completed in preparation for turbo.

It runs, mostly. I am working on the tuning with TunerStdio, very impressed so far. Tuning has slowed down as I am off the road waiting for master cylinder to arrive.

Happy to answer questions if I can.

Cheers,

Jordan

[kbee00]

I will be following this thread intently. I am also going to switch to MSII - Jason has helped me with the parts list but it is a little beyond my budget so I am going to see what you guys come up with. As for the plenum, I found one from a Croma - much better runners but requires removal of the brake booster. But it came with the TPS, injectors, etc. Here is a pic of the plenum:



I plan on the EDIS and Jasons front pulley.

BTW - the Croma draws air from the drivers side - away from the exhaust.

Please keep us updated on your progress - the more details the better.

Thanks!!!!

[FiatMac]

Kbee00,
Questions. Where did you get the Croma manifold? What are the inside diameters of the runners? Can you post a picture from the front? I would like to see where the plenum would be positioned vertically.That is very similar to what I was thinking of trying to fabricate.

Thanks!

[kbee00]

Kbee00,
Questions. Where did you get the Croma manifold? What are the inside diameters of the runners? Can you post a picture from the front? I would like to see where the plenum would be positioned vertically.That is very similar to what I was thinking of trying to fabricate.

Thanks!

I purchased the intake from a guy in Belgum that has loads of new parts. I couldn't find the link, but search ebay UK and you will find him. cost about $300EURO plus shipping - not cheap - but it is brand new and has the injectors and TPS, etc.





Size of openings are approximately 36mm x 41mm - oval. Needs cleaning up / port matching. but the runners almost straight and the air intake faces forward.

Hope this helps