waterinjection.info - Hayabusha-turbo

Quote:

Originally Posted by max_torque

It will be very interesting to see how this pans out!!!

i have a few questions:

1) a turbo motorcycle engine makes peak power at very high rpm (10krpm plus) where the time for charge burn is very rapid, so i can't really see detonation being a big issue. The light weight bottom end and crankcase / drivetrain components prevent you running mega boost at low rpm where Det is a problem? (normal large capacity turbos rely on big BMEP to make lots of torque at low (ish) rpm and hence make lots of power, turbo bikes still rely on rpm, after all a turbo 1 litre car might do say 150 to 200 bhp, a turbo 1 litre bike engine should be seeing 300)

2)On a car installation, approx 10kg of water injection hardware and full resevoir don't knock the pwr to weight ratio much, on a bike i suspect it will be a bigger reduction in accel / braking / C of G etc.

but on the positive side.

3) i guess there's not a lot of room for any aftercooling system on a bike, so maybe this is the big benefit?

Anywhichway, 300 bhp in a bike is probably about 150 too much!! lol! :D

I do what I can to answer the questions to my best ability with waht I have learnt so far:

1) Two things against the turbo bike are preigniton and detonation.

High inlet and engine temperature. Pre-ignition is caused by high valve surface temperature.

Because of the residual latent heat build up within the head and block due to huge power to size ratio is hugh. These enignes now produce 600HP regularly. Because of this, overrich a/f ratio is only means of in-cylinder cooling. Unfortunately rich a/f ratio considerably slowing down the
flame speed there by promoting detonation towards the end gas region. Water injection is the nature choice for direct in-cylinder cooling.

2) The water tank only holds 1.4 litres, very thin wall stainless. The gross weight of the entire WI part is about 5Kg, included full tank of water. This particular bike is a daily driver, it has two boost settings 6psi and 12psi producing 280 -350HP. Boost level is user programmable on each gear for obvious reasons.

3) After cooling? please explain how it work on a four-stroke bike?

If anyone is free tomorrow, Sunday or Monday - there is a WI bike at Santa pod attempting to break his own record set the beginning on this year for a street bike - he ran 7 sec. 1/4 @ 190mph+. His name is Venable - on a specially prepared 550HP turboed Kawasaki by Velocity Racing, Florida.

'Velocity Racing' Boss - Barry Henson will be there for the duration. Plus another eight turbo Hayabushas will be there also - all water injected.