Fully Assembled Wire-In EMS Systems

Contact our Technical Sales Team to discuss the perfect system for your Engine Management Needs!
Email us at websales@diyautotune.com with some details on your vehicle, engine and and must-have features and we’ll make sure you’re pointed in the right direction!


Ready to Rock Engine Management Systems ready to wire and fire!

MS3-Pro Sequential Electronic Fuel Injection and Ignition

The MS3-Pro is our top of the line engine management system. It packs up to 12 fuel channels and 8 ignition channels into a single ruggedized enclosure. This one can run 4 channels of continuously variable valve timing, progressive nitrous control, and more! We’ve taken the optional features on the MS3X (knock control and the real time clock), and made them standard, then shrunk the unit into a smaller, splash-proof case with beefy AMPSEAL connectors. Click here for more details about the MS3-Pro.

MegaSquirt 3 / MS3X Sequential Electronic Fuel Injection and Ignition System

You can’t get more bang for your buck.  The MegaSquirt 3 with MS3X is an incredibly featured packed and highly capable Engine Management System which will control most engines Electronic Fuel Injection and Ignition Systems as well as anything else you’ll find on the market even at 2-5x the price!

With 8 channels of sequential fuel injection, a matching 8 channels of sequential ignition control, and a large number of additional outputs to control everything from Variable Valve Timing (VVT) to multiple stages of progressively controlled Nitrous Oxide, to closed loop turbo boost control and much more, you can do just about anything you’d ever need to do on a race engine with with ECU.

OK, tell me more about all of the Pre-Assembled Wire-In MegaSquirt System options!

Above we’ve already told you about the ‘flagship’ MS3/MS3X systems we offer.  Here is a quick comparison between all of the major versions including MS1, MS2, and MS3 variants, and including a quick comparison of each.

MegaSquirt-IMegaSquirt-IIMegaSquirt-III (with MS3X)
PCB (Mainboard) used in our assemblies
Which PCB Version?
PCB v2.2, v3.0, or v3.57PCB v3.0 or PCBv v3.57PCB v3.57
Firmware version used when making this chartMS1/Extra 029y4MS2/Extra
Fuel control2 channels, bank to bank2 channels, bank to bank
Can be expanded to 4 channel sequential, but it’s not easy.  Recommend MS3/MS3X for that.
8 channels, fully sequential.
An additional two channels can be used for a second stage.  (8 sequential plus 2 batch staged)
Fuel precision100 microseconds0.6 microseconds0.6 microseconds
Ignition controlUp to 6 channels availableUp to 6 channels availableUp to 8 channels available
Idle controlOn / off, PWM (2 or 3 wire)On / off, PWM, stepperOn/ off, PWM, stepper
CommunicationRS232 serialRS232 serialUSB and RS232 serial built in
Data loggingThrough laptopThrough laptopInternal SD Memory Card for on-track recording without a laptop, or optionally datalogging through laptop is also supported.

Note these are just the highlights — there are other things to consider such as the fact that MS3/MS3X have a large number of inputs and outputs that can be used for datalogging extra parameters and controlling more on your engine that the MS1 and MS2 don’t support.  This doesn’t mean the MS1 and MS2 can support many of the same features, for example, Nitrous, multiple electronic fans, Boost control, Knock control, sequential ignition, etc.  All MegaSquirt variants can support these, but the MS1 and MS2 might only have enough outputs to support a few of these options at the same time, while the MS3 with MS3X could support all of them at the same time and still have I/O to spare.  It’s quite the powerhouse, and more than some people NEED, which is why the MS1 and MS2 continue to sell so well for those on a tight budget, and they perform very well, there’s no bigger bang for the buck out there.  They have somewhat similar I/O (Input and Output) capabilities, though the MS2 firmware is much more refined and runs on the faster MS2 processor for a very smooth ride.  For those that have the budget (it’s still very affordable at $640 fully loaded and a bit more for harnesses) to go MS3 with MS3X, you will love it.  The MS3/MS3X runs an even faster CPU with further refined firmware and a huge feature list.  It has has a large number of additional input and outputs to allow for use/datalogging of more sensor inputs and for controlling more goodies with the outputs (fans, water injection, nitrous, whatever you can dream up).  It’s the same bang:buck ratio, just a few more bucks for a much greater featureset (aka much bigger bang for that slightly bigger buck!).

For a very complete feature-by-feature comparison of these different product options, make sure to take a quick look at this page on the MSExtra.com site with a feature comparison chart that goes into great detail!

Which PCB Version?

You’ll see three different PCB’s mentioned above. Our advice — don’t let the PCB version confuse you much — pick the CPU variant you want for the features you need to control your engine, and if you’re project isn’t extremely cost sensitive, run the v3.0 or v3.57 board.  They’re both pretty much equivalent, the v3.57 is largely the same board as the v3.0, it’s just designed to be machine manufactured using tiny surface-mount components instead of the larger thru-hole components used on the v3.0.  Either will do the job nicely.  I prefer the v3.57 myself.

The PCB v2.2 is only offered with the MS1 kits, it’s an older mainboard we keep around that’s pretty bare bones but extremely cost effective so if every dollar counts on your project you can save a few there.  This is popular with low budget race challenge series such as the Grassroots Motorsports Challenge where the budget is extremely tight for the entire car, so cost effective engine management is key!


Although this one has more in common with the pro lineup in that you don’t build it or need to open up the case, its $339 price tag (and that includes the wiring harness) makes it VERY attractive for low budget wire-in installations too.  This small weathertight ECU was originally designed for powersports applications – PWC Watercraft, motorcycles, karts, etc.  But its small size and rugged construction also makes it popular with people who want an ECU that’s easy to put in an inconspicuous location, like street rodders, or racers who want an ECU that will stand up to harsh use, such as road racing or dune buggies/mud crawlers/etc.  This unit has two fuel outputs and two spark outputs allowing sequential fuel and ignition on a two-cylinder, such as a V-Twin, or semi-sequential fueling for a 4cyl engine, or batch fuel for 4-8 cylinders or more.  A PWM output for idle or boost control is included, and two on/off outputs for controlling things like fans or anything else you can dream up that you’d like the ECU to switch on/off in different conditions.  It’s possible to reconfigure it to use these extra on/off outputs as spark outputs as well allowing for sequential ignition on up to 4cyl if you purpose those outputs to the ignition system.  Although most users of this ECU tehnd to be running engines with somewhere from one to four cylinders, it can be, and has been, used on V8 applications for a low cost simple fuel injection and ignition controller with high durability and a tiny footprint.

There is more information on all of these products and more available in our online catalog.