Projects - 16v CIS-E, Converting to Megasquirt

Hey guys and gals, I thought I'd try to make a detailed write up on installing and running megasquirt in a 16v bunny. I guess I'll write everything in sections from start to finish. Here it goes...


First off is layout:
I had CIS-E in the car prior to MS (Megasquirt) so I had to make the decision to either keep everything on the driver's side (default) or put everything on the passenger side, like the mk2 cars. I put lots of thinking into this and came to the conclusion that I wanted to clean things up around the tranny for easier access to things. I decided that I wanted to do everything as right as I could which meant spending a little more cash then I wanted to. When converting everything to the driver's side there are a couple of things you must do. First is the obvious, the intake itself. I ended up using a stock mk2 upper intake mani and mounted that to the lower Rocco one. Second is the throttle cable. I used a stock mk2 cable which worked out pretty good. Everything fit right and worked out nicely.


Second was fuel:
Since I was moving everything to the other side I also had to do something about my fuel feed and return. I followed the hard lines as far back as I could and determined that they came up on the passenger side which made my life a little easier. They basically come up against the fire wall and make a hard 90deg angle over to the driver side of the car. I ended up using a pipe cutter to cut both feed and return lines right below the 90deg angle. At the time I didn't have a flaring tool so I went to a hardware store and bought a couple of compression fittings. The hard line has a outer diameter of 1/4 inch so when you buy them make sure they are for that size. They pretty much slip over the hard line and you tighten them to make a good seal. After that, I used barbed nipple fittings so I could install some rubber fuel injection line towards the front of the car. I decided to run 3/8 feed line and 5/16 return line so I ended up getting the corresponding nipple fittings for each fuel line ran. The whole idea of having rubber line so close to the exhaust really scared me, too. I ended up sliding some thermo sleeve over the the fuel line from the bottom all the way up the the strut tower just for peace of mind.

Now on to the fuel rail, FPR (fuel pressure regulator), and injectors. As many know, the 16v never came with a fuel rail except for the ABD which was not sold here so I needed to order an after market one. There are many on the market and I can't say if one is better than the other. When it was time for me to buy one, BBM (Bahn Brenner Motorsport) had theirs on sale so I purchased the rail and the FPR adaptor from them. By default the rail comes with a straight -6AN feed fitting which is approximately for 3/8 rubber line. Since I had everything on the passenger side I ditched the straight fitting and bought a 180deg -6AN fitting so I could run the line easier and make it look cleaner.

Before I get carried away on the rest of the fuel I almost forgot the injectors. I ended up using a stock set of aba injectors off of a mk3. They are high impedance and flow about 17 lbs/hr which should be enough for any stock application. To use any kind of electronic injector on the 16v head will require Digifant injector inserts. They pretty much screw into your lower intake mani and replace your stock brass inserts. Once you get those in, the fuel rail and injectors mate right up. Also, be sure to use new injector o-rings. We don't want any vacuum leaks keeping your car from running right.

Now that that's all done I'll move on to the FPR. I used a stock 3 bar FPR off of a volvo which is the same as a stock digi 2 FPR. The FPR mounts onto the fuel rail using the FPR adaptor purchased from BBM. It mounts the same way it did on the volvo or a digi 2 car. Earlier in this section I had said that I used 5/16 return line. Now I get to say why. The output of the stock Bosch FPR is a 5/16 nipple so using the 5/16 line worked out perfect. Last but not least is the fuel filter. Since the factory setup had the fuel filter on the driver side of the car I had to think of a plan of relocation. I decided to get a -6AN billet fuel filter from summit. I mounted it inline right against the inner fender well. As of now I still haven't made a bracket to secure it in place so it kinda flops around. Anywho, I think that's pretty much it for the fuel section.


On to the third section, Megasquirt:
This section is gonna be a little less mk1 specific. There are a couple of things you have to decide on to get Megasquirt running on your 16v veedub. First off is the throttle body. You can pretty much use any VW TB (throttle body) as long as it has a TPS (throttle position sensor) on it, or you can make a bracket and add a GM TPS to your existing TB. I took the easy route and bought an automatic Passat TB. It's pretty much the only 16v car that came with a TPS sensor from the factory.

Another obstacle was the intake pipe. I did a lot of looking around and found out that the 92-95 civic (that's right I said it) short ram fit pretty good. I made a couple of modifications to the tube. I first decided to take an inch off the end at the tb side to make it fit a little better. I also had to drill a hole on the bottom side for the intake air temp sensor. After that was all said and done, I sanded and sprayed the pipe black. I used the stock 16v intake elbow which barely fits (really tight) on the pipe but still worked out quite well. For the filter I just bought a generic 3.5 inch cone filter and mounted that up into place. That pretty much sums up the whole intake setup.

Now onto the sensors and Megasquirt layout. For the coolant temp and O2 sensors I ended up using all the stock Bosch stuff. By default, Megasquirt comes pre configured for GM sensors (air & coolant) but you can do as I did and setup the Bosch values for the coolant temp sensor using a program called "Easy Therm". I decided to use the GM air intake temp sensor cause it was cheap and was already configured in MS. It's up to you, though. You can use Bosch all the way around if you'd like. As I said earlier, I used the stock three wire O2 sensor. I fed the signal wire to my relay board and hooked one of the other two (O2 heater) wires to a switched 12v source and grounded the other. Also, there is quite a bit of wiring to do. I made my injector harness and all the other sensor harnesses as well. It's really not as hard as it sounds though.

Now on to the Megasquirt mounting and layout. I ended up getting a relay board to make wiring easier. It's something you don't really need but it makes trouble shooting a whole lot easier. With the relay board in hand I now needed a place to put it. My car isn't a track car or a daily driver but I've been wanting to tear out my heater box for some time now (less weight). This was another reason to remove it. I removed the heater box, sealed up the openings and mounted my relay board in my rain tray. Now that I had all of that done I had to mount the MS box itself. I decided to mount it underneath my passenger side seat so I bought a 6' DB37 cable from RS Autosport. I ran that and a 5/32 size vacuum line under my carpet to the MS box. The reason for the vacuum line is because MS comes with a built in map sensor which needs to be hooked up to some kind of vacuum source to get a map reading. I ended up feeding it into my one-way valve on my brake booster vacuum line.

Alright, we're almost done here. Last but not least is spark. By default the Megasquirt only does fuel but can be "re flashed" (a method of updating the system BIOS or basic input/output system) to run both fuel and spark if need be. Even if you don't want ms to handle your spark I would still recommend re flashing to the ms'n's -Extra code. It's a nice upgrade, in general, mainly giving a 12x12 fuel table over the default 8x8. I decided temporarily that I would use the factory knock setup for spark just to get it out of the way and have one big thing off of the things to do list.

Once I get the fuel all dialed in I'm gonna go to the Ford EDIS coil pack setup (no more oil filled dizzy). Oh yea, one last thing... The ISV. I ditched it cause it's definitely not needed. I went to a machine shop and had a nice block off plate made for 20 bucks, went home and painted it. My car starts right up and idles pretty good considering it doesn't have one. Anywho, I think that's it. I have to thank a bunch of people for helping me out with the whole thing. Thank you martyn_16v, OttawaG60, MidnightGLI, CrackerX, and of course I can't forget my lovely g/f for putting up with me.


Megasquirt Price Breakdown

(All Prices Include Tax And Shipping)

• Throttle Cable...$15.50
• Four Injector O-Ring Kits...$17.93
• Four Digi Injector Inserts...$18.62
• BBM Fuel Rail & FPR Adaptor...$173.72
• Megasquirt PCB v2.2, Relay Board & GM IAT Sensor...$210.00
• Automatic Passat TB...$47.29
• DB37 Cable & GM IAT Connector...$51.72
• 16g Wire & Tape For Harness...$45.33
• 180deg -6 AN fitting & Other Mics Fittings...$27.96
• 96-00 Civic Short Ram Pipe & Filter...$30.77
• 3/8 Fuel Injection Line (Feed), 5/16 Fuel Line (Return) & Hose Clamps...$28.31
• Fuel Pressure Gauge, FP Gauge Fitting, Fuel Filter & Fuel Fittings...$91.13
• More Hose Clamps & 5/32 Vacuum Line...$11.83
• ABA Injectors & Digi 2 FPR...Free
• Dynamat And Thermo Sleeve...$ 24.56
• Zip Ties, Shrink Tube, Wire Sleeving...$39.85