Jet Size for 360BHP WRX?
 

Hi, I am new to this forum and to the world of WI. Well, I have recently had my MY99 JDM WRX tuned to around 350-360bhp and I have now decided to fit the basic 1s aquamist system to my car to help suppress detonation and also to tune for more power if I can. My car has been set up with ECUTEK and is running an IHI VF29 turbo with 440cc injectors,big TMIC etc etc. My car runs on 2 maps with 2 boost settings controlled from an electronic boost controller: Low boost setting:1bar and High boost setting:1.4bar

My question is, what size of jet do I use for my application as I have the 0.5m,0.6m,0.7m jets with the kit? I have also been reading that you get all sorts of flow rates from these jets from this forum as well as else where on the net and im not too sure what jet size to use for the 10% or under mixture to fuel? I will only be using the 1s WI kit to inject water not water/methanol etc. And what would be the best boost pressure to activate the WI at for my setup as the factory 10psi setting for the pressure switch seems too low?

Sorry for all the questions lads but any help I can get on this would be of great help to me as I will be fitting and setting the system up myself then getting my car mapped again with the WI fitted for more power! :)

Thanks, carboy :D

P.S great forum by the way!! :cool:

I like to know the qfr you are intending to run at 1.4bar.

440cc/min of fuel for 350-360 injectors are very closed to the optimum /lean limit. You really needed to start with the biggest jet (0.7) and work upwards. What is the maximum duty cycle you run on your injector?

Hi Richard, thanks for your reply to this! I am not too sure what you mean when you say "qfr"? I am new to the world of tuning and I have someone else tune my car for me, so I will have to ask them what the max duty cycle they have run on my injectors? Well, I have a Sytec Motorsport fuel pump running at 160l/h and also a Sytec FPR fitted to my car, so maybe the guy who has mapped my car etc has tweaked the FPR to get a little more out the injectors? I am not too keen on going to bigger injectors as I know you get a better atomised fuel/air mixture with smaller jets. Also is the optimum water/fuel mix not around 10% or less? I was wondering also, what flow rate/min will I get with the 0.7 jet in real time? Thanks, Carboy

My bad typing I meant afr. (air fuel ratio).

I was a bit concern that you may be running your car far too lean.

350-360BHP, is it at the wheels or flywheel?

i my experience with vf29's tells me your injectors are not enough.
i would suggest pinks, 550 cc, or util you can post a log with your
injector duty cycles and air fuel ratios. better to be safe than sorry
when it comes to the amount of fuel.

160 lph is stock for wrx.
180 lph is stock for sti


but Richard is correct about possibly running lean.

on a side note. I have 0.8 tapped into my tmic.

How much HP are you curently running witj 4x 550cc?

Arwe you using water or methanol?

Richard,
not sure if the question is for carboy or myself.
just in case, I'm running 50/50 mix.

but using a conversion factor of 227/165 = 1.37
that might be abit too optimisitc, but 1.33 seems correct

low boost 275 whp = ~366 hp
high boost 315 whp = ~419 hp