What Cc?

[jermzfree]

I am trying to dial in my water injection for 10-12 lbs of boost. There are some nice equations floating around the internet to help dial in the water injection nozzle size. They all ask for fuel cc/min flow at peak boost. Does anyone know how thirsty the Hayabusa is between 250hp-3oohp? Any help is greatly appreciated!

 

[hendrixgr]

Have a look here for info https://www.rbracing-rsr.com/waterinjection.html
My hayabusa with 12 psi burns 5 cc of fuel of fuel per hp per minute which means 1430-1500 cc for 286 hp per minute for all 4 cylinders.
I would use a progressive controller with boost and rpm reference injecting 15% water to fuel ratio max but you can go as high as 20% maximum without noticeable power loses.
For 1500 cc/min that means 225 cc of water per minute.
I find the 12% water injection that the link i gave you use a little low, aim for 15%
(I just found my past calculations based on actual measurements)
Chris

 

[jermzfree]

Have a look here for info https://www.rbracing-rsr.com/waterinjection.html
My hayabusa with 12 psi burns 5 cc of fuel of fuel per hp per minute which means 1430-1500 cc for 286 hp per minute for all 4 cylinders.
I would use a progressive controller with boost and rpm reference injecting 15% water to fuel ratio max but you can go as high as 20% maximum without noticeable power loses.
For 1500 cc/min that means 225 cc of water per minute.
I find the 12% water injection that the link i gave you use a little low, aim for 15%
(I just found my past calculations based on actual measurements)
Chris

Thank you hendrixr. That is some great info. I plan to use a progressive water injection controller when I move to 12lbs. But first 9lbs with just a hobbs switch. Can you tell me what you use that has rpm referencing for the water injection? Thanks.

 

[hendrixgr]

I have built my own controler with an Avr cpu and the pressure sensor output from the AEM failsafe but if i had money the Aem water injection controller looks nice and it works well as i hear.
I use he same pump as AEM.
Chris

 

[jermzfree]

I have built my own controler with an Avr cpu and the pressure sensor output from the AEM failsafe but if i had money the Aem water injection controller looks nice and it works well as i hear.
I use he same pump as AEM.
Chris

Good to know. That is also my plan. 9lbs base spring. adding boost controller and AEM injection controller for 12lbs. Thanks!