- The purpose of this tuning exercise was to see what power a basic JR
Supercharged Type R would make with the correct ignition and fuelling.
After the baseline run was done, the rising rate regulator was
removed, the ignition timing returned to stock, the MAP sensor was
relocated to see boost, the air temperature sensor was returned to
stock operation and larger RC 440 injectors were installed. Fuel
pressure was set to 50 psi by using a B&M FPR ($55). Injector duty
cycle reached 75%. We are not sure if the fuel pump was stock, but we
are sure the stock fuel pump would
have been sufficient at the lower fuel
- After 4 dyno pulls we had 200 hp. VTEC was lowered to 5000 RPM
giving a 13 HP increase at 5500 RPM. The remainder of the dyno runs
were mainly dedicated to tuning the part throttle tuning and making
sure detonation was eliminated. Cam timing was advanced 4 degrees.
While this is good for a NA car, we suspect returning it to zero will
perhaps gain 5-7 HP at 9000 RPM. This is a low boost engine with a big
pulley. We were looking for a smooth torque curve and are happy with
what we achieved. Part throttle response was much improved, but not
shown on this chart. Below 3500 RPM a little more tuning is necessary.
We suspect we may have retarded the ignition under boost a little too
- Intake temperatures were interesting. While on the dyno intake
temperatures were around 145-155 F rising to about 167 F. After the
run, the intake temperatures continued rising. This setup would really
benefit from bypassing the throttle body heating, bypassing the IAC
heating and installing a heatshield gasket.
More boost will probably heat the intake charge more.
- This engine is now set for instaling a smaller pulley for more
boost. We can still use the stock fuel pump, and would probably only
need to raise the fuel pressure by about 5 psi.
- At the higher boost levels JRSC customers spend a bit to get their
systems functioning well. The Hondata install costs about the same, is
far simpler and works much better. Check out a cost comparison and
pictorial install here.