- (B16A) with a P28 OBD I ECU conversion tuned to gain 5 peak HP at
7500 RPM, 10-12% torque below 3000 rpm and an average of 3.5 hp over
the whole rev range.
- The engine was stock apart from a heatshield gasket and the tuning
was performed on a dyno. The result of this surprised us. Normally the
stock tuning is fairly close to the full potential of the engine, and
there are no significant gains made by tuning fuel and ignition
tables. Using a wide band lambda meter on the dyno we increased output
by leaning the mixture at full throttle and richening the mixture at
- The biggest gain came from advancing the ignition timing below 5000
rpm across all load settings, and retarding the ignition timing at
7000 rpm for full load. Our feeling is that Honda has tuned the engine
to run on a lower octane rating fuel. The same gains could not be made
by increasing the base timing (by spinning the distributor) because
the engine made more power over 7000 rpm by retarding the timing. The
difference was noticable when driving the car, especially at part
throttle and low rpm.
- On the freeway we found the car would comfortably climb a hill in
5th gear where previously a change down to 4th was necessary. Tests
were performed as accurately as possible on a dyno with the engine
water temperature and intake air temperature at the same point at the
start of each run.
- We also installed RC 440cc injectors, re-calibrated the fuel trim
and proved that the bigger injectors gave exactly the same output as
the standard injectors with no loss in drivability.