View Full Version : 11.0:1 CR Normally Aspirated Honda engine. Candidate for WI?

21-02-2007, 01:58 PM
I have a JDM 1999 Honda SiR-T, imported to Jamaica. The car has a DOHC F20B engine (destroked H22) that's tuned to run on 98RON fuel readily available in Japan. In Jamaica, the highest octane available at the pump is 90 octane (using the 'R+M/2' measure - which is roughly equivalent to 95RON) and we have an average temperature of mid-80's year-round; summer temps of mid-high 90's are not uncommon.

While the car runs well for the most part, the ECU does reduce the timing and performance suffers somewhat. During hard driving on hot days, the ECU will occassionally SEVERELY reduce timing and has to be reset before the car will return to normal.

I have been advised that water injection could help solve my problem.


a) Can Water Injection indeed help solve my problem? Would the water injection give me an 'effective' 98RON octane?

b) Which (if any) of the aquamist models are best suited for Normally Aspirated (NA) engines?

c) Would regular water be sufficient? Or would I need to use methanol for even more of an octane boost?

d) Which is (are) the best inputs? Throttle position? Engine RPM? Engine Vacuum?

Thanks in advance.