[bjmercer]

Does changing the ecu really make a difference? If so, what does it do? Which brand is the best in ecu's? I only ask because there is an optimal air fuel mix that the stock ecu and o2 sensors try to maintain to make the car run correctly. If you get an ecu that changes that mix than the car won't run to its full potential.

 

[JDM Spec]

Only get ecu with the brand you are going with.

For example Mugen parts then go with Mugen ECU because they are tuned to work together.

 

[Dj K-otik]

I've read the Mugen ECU is makes a big difference over stock. I think it helps with the low end alot. However, it isn't programmable and is "for race use only," so it voids the warranty. Spoon makes a racing ECU also, but I'm not sure if it's programmable. They both run about the same price ($1,000+). I think AEM has one for the S2K also, not sure though . . . but it could be considerably less and would probably be programmable.

Another route you might want to consider is a VAF-C. They are considerably less and if properly tuned, they yield some good power gains. Also, there's the new Greddy E-Management system, which does the same thing with the a/f ratios that ECUs and VAF-Cs do . . .

 

[JDM Spec]

Spoon ECU makes a big difference after VTEC.

 

[JDM Spec]

Amuse makes ECU too.