Megasquirt ECU Wanted

[lanciahf]

Anyone selling a Megasquirt ECU. Looking to convert but little short of cash at the moment.

Thanks,
Ralph

[DJ]

Buy Jim's Beta Coupe and I'll swap you mine for it. :-)

Sometimes you can find them on Craig's List if you spend the time to look around the country. eBay sometimes has them but the deals aren't normally that much better than buying one new.

If all you want to do is control fuel, you can get by handily with the MS 1 and you can get the kit for as little as $139.00 if you want to care to build it yourself. DIY Autotune (www.diyautotune.com) is the best place to buy IMHO. Great folks and great support.

[lanciahf]

I thought with our low impendence injectors I would need MegaSquirt V3.0.

[DJ]

You mean the 3.0 PCB. No such thing as MS 3.0 yet.

It's all a bit confusing at first but it's really pretty simple.

There is MS I and MS II. MS II is simply a replacement daughter board for the MS I processor which adds some capability and a faster processor.

There are also 3 different current PCBs: 2.2, 3.0, and 3.57. The version 3 boards are a bit more robust and have added capabilities that are enumerated elsewhere so I won't try to here. The 3.57 boards simply use surface mount devices (SMD) which facilitates mass production using automated equipment. They are more difficult to repair but also (generally) a bit less likely to need repair or suffer from errors/defects in manual assembly.

The version 2.xx PCBs require either external resistors or a flyback board daughter card if you want to stick with the stock low-impedance injectors. Both options are pretty cheap. Someone like John Allen or Scott Hay could advise you on all this much better than I can, though.

[John Allen]

Sounds like you have it covered. I like the simplicity of resistors over the daughter board.

The only thing I would add is that the older v2.2 boards and MS1 can do ignition with the right code installed. It won't do true coil-on-plug, but it will do mapped distributor ignition and Ford EDIS distributorless ignition.

Be careful of buying a homebuilt kit from eBay, some are built very poorly and may not even work. If you aren't building it yourself, save time/trouble and buy a prebuilt kit from a vendor on the MS website.

[lanciahf]

So John,

Are you saying for fuel control only I should get the PCB 2.2 with resistors, instead of PCB 3.0. BTW I have a set of Volvo resistors I pulled from a junkyard a while ago, not clear on how to use them. The whole pack looks sort of like a heat sink.

Also can you recommend a megasquirt ready TPS that can be used with the spider manifold.

Sorry for the newbie questions.
Thanks,
Ralph

[John Allen]

the v2.2 board can be used for fuel only OR fuel/ignition with the "extra" version of the code. The resistors are wired in series with each injector (the central "power" wire of the pack goes to 12v switched and the 4 outputs go to each injector).

There is a bolt on TPS that fits the stock 124 manifold, but it is a little spendy and not common. The TPS off of a Ducati or MotoGuzzi fits directly on the manifold. It is made by Weber, is black and has the number "PC10" etched in it. I was able to get one attached to a set of throttle bodies on eBay. It may be the only way to get one at a reasonable price. The one I had is now in DJ's hands and his latest pictures shows it.

The only real alternative is to get a TPS from a late Volvo, SAAB or Kia/Hyundai and make up a 1/4" aluminum plate that 'clocks' (rotates) the TPS to the correct position and adapts the bolt pattern. I had pictures of mine in the photo section, not sure if they are still there...

IMHO the v2.2 and MS1 is more than adequate for a FIAT, the v3.0 and MS2 is just more bangs and whisles that may or may not ever get used. If you go with a v2.2, there is more modifications to add functions (like ignition). These mods are not too difficult, but do require some electrical/soldering experience. If that's not for you, consider a v3.0.

-John

[DJ]

FWIW, I went with a MS II with 3.57 PCB. The primary reason is that the MS II includes Idle Air Controller circuitry. I went with the more capable IAC because I live at higher elevations and most of my Scorpion driving is in the mountains at widely varying elevations.

Adequate idle is one of those things I've always battled with here in Colorado and I simply decided to go with the best available setup. I also added a dual MAP sensor for real-time barometric correction for the same reasons and added the internal Bosch ignition module for controlling spark so I don't need any external ignition modules.