New to MazdaSpeed World, need a little help

Mod edit: I added proper grammar and punctuation to make your post more readable. The easier it is to read your post, the more likely it is that someone will understand what you're asking and provide some help.

I have a 2002 Mazdaspeed protege. I need to know some things about this car. What computer and wire harness is compatible with this engine? I have a couple different computers and I have a harness that I need to put in the car. I just purchased the car, it has a built motor, it has Pistons that has rods, has a cheap big eBay turbo.

I'm not new to the car scene. I have a 92 VW Golf GTI with a VR6 swap that I did myself about 10 years ago, and I am getting ready to put a turbo kit on it. In the meantime, I picked up this Mazdaspeed Protege for cheap and trying to get it running.

Whoever had it before has been chewing on the wire harness, so I pulled a wire harness out of the junkyard and I am going to install it right now as we speak. If anybody has any suggestions or comments or anything that would help me, that would be greatly appreciated.

I don't know if this is the factory ECU that came with the car, but it looks like it's MJJ8 MSPO-18881. Is that correct? Is this a Mazdaspeed Protege Computer ECM and how much boost will this car run stock on stock engine? Obviously not what's been done to this car but what is the stock engine good for? I also have a couple different computers XMU2 FS8L-1881-C UID2 FS8M- 18881-C which is
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2003 MazdaSpeed Protege
The stock computer / MAF / Injectors do not have alot of headroom for making more power.

If you start to flow more air than the stock setup can compensate for then you will hit "fuel cut" which is basically the stock ECU trying to save the engine as there is no way for it to add the correct amount of fuel once the MAF hit max voltage.

To further complicate the issue if you live in a cold climate and have an aftermarket intake on the car you can hit fuel cut quite easily.

Common upgrades are the SS AFC, wrx 440cc injectors OR other more expensive (better) EMS solutions.

Do some reading around the forums of old posts or build theeds before spending any money to get an idea of what you are looking to do.

You can easily spend more than the car is worth trying to chase some stupid HP goal because on paper it sounds great to tell people you make XXX whp.

These engines as not as tough as other OEM vehicles so you need to take small steps ensuring that you do things right along the way or it will break fairly quickly.

Smart things to do include not being overly aggressive with the throttle at lower RPM especially in 5th on the highway as surges in low end torque are not handled well by the bottom end. The stock Limited slip differential is also a known weak point.

It is fairly easy to get the car up to 200-220whp reliably as long as you are not beating on the car for the sake of being on the car. you need to know what you are doing and be willing to take some risks with the drive train and connecting rods if you are interested in really turning up the power levels.

These vehicles appreciate mechanical sympathy.

Banging 1-2 all day will result in damaged transmissions/differentials over time.

Keep in mind when new the car outhandled it's rivals and that was the selling point.

it was priced significantly less than a WRX or RSX or SRT4 so do not expect the engine or trans to survive like it is a K20.

When it was so much less than the competition they had to leave things out (built engine/trans) so do not be surprised when you see how many people have had issues trying to boost like they bought a car that costed 5-10k more new.

When you compared price new VS it's rivals this car was an amazing deal. I shopped everything near it in the price range and this was by far the best bang for the buck. To top it off Mazda was offering 0% financing for 60 months etc. It was a great deal.

When shopping used an MSP is basically the same price as everything else so really you are buying it because you really like it, not because you are going to get to 300+hp easily (or at all for most with stock drivetrain).

Just some things to think about. Enjoy the car, I sure wish I still had mine it was such a blast.



lol I'm still having trouble believing you found a good wiring harness for an MSP at a junk yard.

You've definitely got luck on your side. (y)