ECU programming

[niky]

You take a laptop, open up a numbers table (it looks like a giant Excel sheet), and, armed with an O2 sensor and a dyno, you fiddle with values on the table, increasing fuel here, adding timing there, etcetera... all the while, double checking the air-fuel ratio via the O2 sensor (if you're on the dyno, they usually have a tail-pipe one, or if you have a relatively sophisticated set-up, via a wideband sensor plugged into the exhaust where the factory sensors go...). Once you're satisfied with the changes, you download them to the ECU or chip you're programming.

Different ECUs and tuning programs look different, but basically, most of them look like this. The strange thing in FnF is seeing people tweaking things on the strip... that's total BS. You have the car dialled in beforehand and you have presets loaded in... you just switch between the presets (for example, switch it to the race-gas, nitrous or high-boost setting... etcetera) before your run and leave it as such. You can tune it on the road, but you don't usually do it standing still... you do it while cruising along to program the part-throttle and full-throttle maps under a realistic load.

The interface itself is easy to use... they can't force tuners to use some cryptic programming language, otherwise their products won't sell... but you have to have a fairly good idea about throttle, ignition and fuel mapping to use it... and with newer Honda programmers, you have to learn a bit about variable cam timing, too... most of these things have pre-programmed "base" maps, with average values already pre-loaded for your particular engine. All that's left to do is adjust them for your set-up... but on the more expensive standalone systems, base map applications aren't widely available, and it can take a ton of tweaking to get it to the point where the engine is anywhere close to streetable...