smg944

iTrader: (34)

i have currently already setup the coolingmist 250psi pump kicking on a 10psi and i only have a 300cc injector currently. im assuming im going to need atleast 500cc of AI. im somewhat new to AI but i dont want to have to switch from race gas back to pump all the time. i am looking to run 20psi on 93 pump and AI. from what i have read it seams that i am only going to need water but i would like to get some solid imput incase im missing anything. the injector is setup right in the throttle body also.

my current engine setup is a large streetport, billet 6765 with a 1.00 t4, 850/2000cc injectors, twin pumps. any help is appreciated.

Liborek

Question is what you are after

Water is best knock suppressant and potentially best charge coolant. Problem is that this huge potential only happens at boiling point of water. So water users aren´t reporting such huge drop in IATs. But still, water does its magic in combustion chamber. Methanol is fuel and thanks to lower boiling point good charge coolant. Sometimes its good to take advantage of both fluids. But then you should tune for added fuel value. Ignition system will determine how much water you can run without power loss. Then sky is the limit

smg944

iTrader: (34)

i mainly want to run it at 20psi no crazy timing or anything. just want to keep the torque and some power of the higher boost. i dont mind tuning in for the fuel content of meth but if i dont need it and can get away with just 500cc of water at 20psi that that will work. i guess i can give it a shot and see where my egt temps end up with just water.

Liborek

And I hoped you would wind it up atleast to 30 psi

Don´t get caught much about EGT hype. Without knowing EGT at lean best torque its just useless number not applicable to given engine.

Overal turbine inlet pressure will also influence EGTs.

Also EGT behave inversely to combustion temps and combustion chamber temperature for that matter. So shooting for some particular number is BS - as long as turbine components can live at such temperature.

This is really subject that cannot be generalized for some number

You will be fine with water only. But ignition system will dictate limits.

ryan1

iTrader: (5)

At 22 psi on a 6765, Kan stopped raising boost because he said with 900cc of water I was at the limit. I had zero knock, but he wasn't comfortable pushing any harder until I had more water cc available.

Speed of light

iTrader: (8)

.....Or hydrostatic lock, whichever occurs first.

But seriously folks,

I have been very happy with about 375 cc/min at 18PSI in a 2 stage arrangement.

IMO 300 - 500cc/min is the correct range for your setup. You only need enough to get the job done and it really doesn't take very much (water)--so there's a safety margin even at the lower delivery rate. What a lot of water will do for sure is empty the tank faster.

Liborek

I forgot that one Is there some way to calculate how much fluid would have to be pumped in at given engine speed to hydrolock? Given that chamber at TDC have 75 ml at 9.7 CR for example

Precisely. Just enough and little bit more approach is probably best, and fluid consumption is something what really matters.
Better with 500cc and half of tank than 1000cc of nothing