My latest Megasquirt install, MS2 w/ITBs, wasted spark, relay board and custom harness Options

[aircooledtechguy]

Megasquirt EFI is an amazingly capable system that is 100% tuneable. It is, however a mis-understood system and many of it's detractors have either not actually used it themselves or have used a cobbled together system of mis-matched parts. After 8 year of working with Megasquirt and doing installs, I have found that buying a complete, well engineered system with a quality harness is key to success. Also having an expert tuner can't hurt either.

Some may know that I work closely with Mario Velotta from The Dub Shop for all my Megasquirt parts and kits as well as tuning help. Here's a very typical install of one of his kits. You don't need the buy the most expensive kits to get a great running car and Mario will not up-sell you things you don't need for your application.

This install was on a 914 2.0L that had factory D-jetronic. Normally we would keep it plenum based re-using much of the factory parts, but with the TB badly worn and this clients desire to clean-up the engine bay, so we went with 40mm ITBs with modern 32# injectors. Ignition is a crank triggered (36-1 wheel mounted behind the fan w/ a bracket and hall sensor) using a coil pack and 8mm plug wires. Exhaust sampling is with an Innovate LC2 All sensors are wired through custom made harnesses. These feed into a relay board. This relay board is not a piece that is 100% necessary to use, but I feel it simplifies and cleans-up the install by getting all fuses and relays used into one neat, clean compact footprint.

The install took about 2 days. This included careful removal of the old D-jet system and installation of all the components is the new system. We chose to mount this system in the fwd, right end of the rear trunk. Probably the most difficult part of the install was installing the hall sensor bracket with the engine in place. While totally doable, it was a tedious part of the job.

Mario came out to assist in the in-car tuning. The result of a 2-2.5 hour drive is smooth as silk driving from idle to red line, under light throttle or heavy. Acceleration is smooth. No bucking, burping or farting Here is a short video of the test-drive and an over view of the install.

https://www.youtube.com/watch?v=e9rcczRTG_M...e=youtube_gdata

[Dtjaden]

Mario could easily put this type of kit together. Although I only have bought a few parts from him I can attest to his capabilities.

In my Megasquirt system I decided to use as much of the existing D-Jet system as possible both to reduce cost and because of the challenge. My engine is a 2056cc with a Webcam #86 camshaft which is slightly more aggressive than stock. The Megasquirt ECU controls both fuel injection and ignition. The D-Jet parts I reused are, starting from the top:
- Air filter box
- Throttle body
- Plenium
- Intake runners
- Fuel injectors
- Cylinder head temp sensor
- Fuel pressure regulator

Things I added:
- Crankshaft position sensor and wheel (The Dub Shop ~$140)
- Intake air temp sensor (GM part, ~$15)
- GM LS2 ignition coils, one per cyl. (eBay ~$60 total)
- Throttle position sensor (Bosch, used ~$20)
- FI fuel pump and filters located in front trunk (Walbro ~$150)
- Wideband O2 sensor and cockpit gauge (innovate ~$200)
- Megasquirt MS3X (DIY Autotune ~$490 as kit, $660 fully assembled)
- Wiring harness (DIY Autotune ~$80)
- Injector driver board (Jbperf ~$60 kit)

I made my own relay, fuse and terminal board that I also use to mount the Megasquirt enclosure. My cost for that was about $50. Finally I used Delphi Weather Pack connectors throughout including two 22 pin bulkhead connectors thru the back trunk. That lets me drop the engine by just unlocking a handful of connections. All told about $100 worth of connectors.

My cost into this part of the Megasquirt system is about $1,600. This includes some miscellaneous tools and automotive wiring that is not a one time expense. So, if I would sell the Webers, fuel pump and distributor that I took off my net for the Megasquirt system would be $700 - $800. And it was a fun project!