Since I purchased the car, the main limitation was the standard ECU. The car had an assortment of issues, such as a very high idle, poor starting when cold, leaning out in the upper rev-range, and sometimes hesitating/misfiring under boost. Doesn’t sound very fun, does it?
The mighty FJ20 nestled between the strut towers needed to take orders from a new boss…
…So the decision was made to run a Microtech LT-10s, as it provided everything I required while still being affordable compared to some of the more complex and higher priced ECU’s on the market.
While the car was in the shop having it’s new brain installed, I took the opportunity to have the wiring neatened up. Here is how the engine bay used to look. The large loom that runs behind the engine near the wiper motor was moved to inside the car, and it now enters the engine bay through a hole in the firewall near the intake manifold, out of site. Also the Microtech negates the need for the restrictive airflow meter, so that has gone to greener pastures and taken the airbox with it. Scroll down to see how it looks now.
Much better! I’m very happy with the cleaner look. Still a lot of work to do to make look the way I want it to, but getting that thick loom out of the bay is a big step. More engine bay work will commence next year.
So, how did the engine respond to the new ECU? The first thing you notice is the engine starts up first go like a new car, then you hear it idle at around 1000rpm instead of 1500+. That would have been enough to make me happy, but once you start driving it the real gains can be felt. The car is much, much quicker now, and smoother. No more missing, coughing, or leaning out, it pulls all the way through the revs with an intense intake noise that leaves me wondering if I’ll find a small bird stuck to the air filter next time I pop the bonnet. The car is finally at a level where I now feel satisfied that it has bridged the power gap that was left when I sold my S15. It really feels like a whole new car now. On to the magic numbers…
Before: 121.0kw @ 7psi
After: 154.7kw @ 12psi
155kw at the wheels in a car weighing less that a tonne makes for a pretty fun drive. Remember the engine is not intercooled yet.Â That will be rectified next year when the car will receive an alloy radiator, front mount intercooler (purchased), modified intake manifold (purchased), and an electric water pump to free up some room in the engine bay for thermo fans. Then we can wind up the boost to around 16psi. Not bad for a stock engine with 3″ exhaust.
How are the wheels going? One has been polished and painted, 3 more to go. I did a quick mock up next to the car to see how they’re going to look, now I can’t wait to get them on.
Hopefully they’ll all be done in the next couple of weeks.