Megasquirted … Sunbird?

Who in their right mind would do such a thing? The same kind of nutcase that would add nitrous to one I guess! Seriously though, I think the 2.0 is really a reliable engine and although they are not very popular around here, they have a decent following in various forms in Europe and other parts of the world, particularly the 16 valve variants which share the same block as the 8 valve version. Although the 8v setup may not support big power numbers, enough extra can be extracted from it to make it a fun and fair performer in my opinion. Pairing a bottom end built to handle it and a fair shot of the juice, it should provide all the extra power I want in short bursts like the occasional dragway flogging. This is where the Megasquirting comes in: the factory computer for this car just doesn’t have any support in contrast to some of the more popular GM ECUs when it comes to modifications and tuning. So I decided MS was the way to go (plus I had already built this one.)  I’ll be able to compensate for the aftermarket cam, hopefully a ported head at some point, some better flowing exhaust, and I have kicked around the ITB idea also, but not sure about that one yet … the factory intake and bored throttle body will be the first phase intake-wise.

The Project So Far:
It has now run multiple times on Megasquirt, but is not full time yet. I have been waiting to do any real tuning until I could change my wideband situation, which now I have. Since this a little bit of an odd setup, it took me some time and help from experts over at the msextra forums to get everything sorted out such as mods to the MS board, settings, and so on. Once everything is all completely done and all of my notes are sorted out I intend to share in detail everything that has to be done to get the 2.0L port fuel injected Pontiac motor running (in this future post: Megasquirted: Sunbird.)  First I’ll probably see if I can get a decent tune going on the stock engine.  When I get a handle on that I’ll begin running the Megasquirt daily, and then I’ll be comfortable with doing some of the engine mods and updating the tune to suit them.

Above is the basic summary, so stop here if you don’t want to get into some specifics of what’s been done to get to this point.
First is the version 3.0 board with a Megasquirt 1 processor. Not fancy, considering MS3 is now out, but plenty functional. Other than the regular stuff, I had to add 3 things to the proto area; two circuits to control the coil pack/ignition module, and one to send a signal for a tachometer. The ignition seems to work fine so far, but no luck on the tach yet, it may need some tweaking. To get MS hooked up to the engine I found a factory computer to pirate the connector from and built an adapter to go straight from MS to the factory wiring. Desoldering all the pins from the computer is a bit of a pain, but the convenience of being able to switch back and forth from stock computer to MS during testing made it worth the effort. The MS end of the harness was a DIYAutotune harness that I cut. Also had to run a vacuum line into the car to hook to the MS MAP sensor. It’s just a temporary setup right now. Now I need to set up the JAW for a wideband output instead of narrowband simulation, then I may be able to do some more tuning. I just got it running on the narrow sim, but didn’t want to drive that way. For tuning I’m using a 1.4Ghz Celeron laptop running Linux Mint9 LXDE and TunerStudio MS Lite. I started out with MegaTunix, but was having some problems so I switched, and I think I like the TunerStudio better. For what it’s worth, the laptop originally had 256mb of RAM and handled it ok as long as you weren’t doing anything else, but I put in 2GB later on because it was cheap and easy and it sped things up tremendously. Anyway, my post about the finished result will go into much more detail about everything, this is just a generic update for now.

newman cam

2.0L cam from England!

Sunbird Megasquirt

Megasquirt1 pcb3.0 with tuning cable and the Sunbird adapter harness.

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