MegaSquirt

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Megasquirt is a relatively low-cost electronic engine controller that several Datsun1200.com club members are using to control their A-series engines. It can control Fuel Injection and ignition (spark) both, although for spark-only the MegaJolt-EDIS product is less expensive and simpler to install. Variations include the original MegaSquirt, MegaSquirt II (MS-II) and the latest MicroSquirt. The MicroSquirt is the same as MS-II but in a small sealed case. MegaSquirt is used on the most pedestrian of stock engines, to all out racing cars.

For general info, see: wikipedia:Megasquirt

For Frequently asked questions, see 
* MegaManual
* DIYautoTune

Comparison

The MegaSquirt controller is a relatively low-cost -- relative to other aftermarket engine computers. MegaSquirt kits start at about $200 USD.

From least expensive to most:

1. OEM engine controller (used, $25-up)
2. MegaSquirt solder-together kit ($140-up)
3. MegaSquirt completed product ($240-up)
4. MegaSquirt-II hardware kit ($250-up)
5. MegaSquirt-II assembled ($400)
6. MicroSquirt ($400)
7. HALtech, Wolfe, and other aftermarket "custom" ECU systems ($700-$2500)

MegaSquirt software has evolved to the point where it is arguably as sophisticated as the more expensive designs.

The newer MegaSquirt-II from 2005 has hardware that matches the more expensive designs, notably:

• Ignition control (distributorless systems)
• CAN-bus support
• 16-bit processor

Club Users

• Finn: MegaSquirt controlling the world's quickest A-series engine

Kit

Many users choose the solder-together MegaSquirt Kit. The Kit is about half the price of an assembled unit.

• If you have ever successfully soldered any electronic kit, even a simple one, you should be able to assemble a MegaSquirt.
• Time to assemble is about
• As with any other universal engine controller, the user will have to careful select and configure part, then tune the system. It can be difficult to get the tuning "right".

Usage

When do you need a MegaSquirt? If you are using EFI. You will need some kind of controller for it. If you are adapting an OEM fuel injection system, you can use the OEM computer which is cheap at the wreckers. But for highly customized engines, MegaSquirt will give you that fine tuning.

Question:I want to fit crank-trigger or coil-on-pack ignition. Is MegaSquirt for me?

Answer: You can use MegaJolt-EDIS instead. But the MegaSquirt-II code can also control the ignition, though it is about double the price. You will also need to download the software "MegaSquirt-N-Spark Extra" (MSnS-E) or other alternative software.

• MegaSquirt-II code can run on a MegaSquirt-I board, and control spark.

Board Versions

• V1: original board revision, no longer available
• V2.2: V2.2 is printed in the upper left corner of the printed circuit board
• V3: can be fitted with MegaSquirt-I (8-bit) processor, or with MegaSquirt-II (16-bit) processor
• V3.57: MegaSquirt II surface-mount board (non-kit board)

Parts Needed

• EFI system, your choice of manifold, injectors and throttle body. MegaSquirt can handle most brands of injectors
• Megasquirt unit
• For a kit: you may wish to get the Stimulator ($45-up kit) to test your board during the put-together phase. The Stimulator emulates all the engine sensors to fully test each part of your kit board.
• Wires to wire it together ($0 if you have wiring sitting around, $65 new)
• Oxygen sensor (optional but recommended)
• MAP (vacuum) sensor or TPS (throttle position) sensor. Again, any brand (Ford, GM, Nissan, etc) may be used.
• Air temp sensor
• Water temp sensor
• Boosted engines: High-bar MAP sensor for over 1.5 bar ($65)
• Windows-based PC or laptop to run the MegaTune software to configure your system
  • Serial RS-232 "COM port" cable (about $5 new)

The sensors are usually the General Motors type, although you can recalibrate the controller to use other brands. Remember to "Keep it all Nissan".

Sellers

Where can I buy a MegaSquirt? From an authorized seller. See the list at http://www.megamanual.com/MS%20FAQ.htm#order

You can also find pre-assembled units on eBay, however beware they often cost more than from an authorized seller.