Moddify Your S15
This section is not really a modification guide. There is plenty of information out on the net and on forums about how to modify these cars. I've just included here a few of the areas I've looked into or played with which people may find useful.
This is often an area which is overlooked when lightly modifying a car. When people get beyond a certain state of tune they usually ditch the factory ECU in favour of an after market computer such as the Apexi Power FC. I haven't got far enough with my car to do that and quite frankly if you buy an after market ECU then you're talking at least NZ$2k to get it running your car correctly.
If you don't want to go aftermarket then modifying the factory ECU with a 'daughterboard' and custom tune is in fact quite cost effective. In New Zealand there seems to be a few places that can do this for the factory ECU and in fact a properly tuned factory ECU can support well over 200kw at the wheels. For my car I bought a second hand ECU with a Gizzmo chip already installed. While not ideal it was very cheap, was tuned for exhaust, pod filter and near factory boost and also came with a dyno graph of the car it was last in.
The other great thing about the factory ECU is the fact you can with the right interface plug a laptop into the cars data port and extract a lot of very useful statistics. I decided to build my own ECU to laptop interface module and downloaded some free software which allowed me to communicate with the ECU. This sort of thing is very useful to
- Check fault codes for diagnosing car problems
- Graph and monitor most of your engines parameters
- Perform active tests
- Check to see if you're getting near the limits of things like the MAF or Injector duty cycle
For example I was able to use the laptop to log data as I did a 2-3rd gear acceleration run and could see how close to the limit of my factory MAF I was, check the duty cycle to make sure it wasn't too high, look at the timing and look at the lambda sensor readings.
I'd recommend you check out PLMS development web site and have a look at what involved and what it can show you.
More to come
There must be more I can add here