Thread: Inj Size And WHP Output,

ok thanks. sorry for the noobness

Guess I'll be swapping my injectors now lol. Thought the stockers were good for more than 175. To add to it mine probably have 200k miles on them as well lol.

Does the Ecu NEED to know that im running four bar or can I just turn the pressure up at idle and compensate with my SAFC?

Compensating with the SAFC is the same as the ECU being programmed for 4bar. The ECU doesn't really KNOW you're running at four bar, it's what you program as the K value, etc.

For instance, we know that 370cc injectors at 4bar are ~420cc injector equivelants. Now you just need the K value for 420cc injectors w/ your specific MAF, as well as fine tuning the latency values etc. and you're done.

ok so i have a few questions....

im working on trying a GTi-R manifold/plenum assy on my 10:1 DE(w/shaved head and .020 head gasket.... so obviously more than 10:1). the ECU is for stock 259 side feeds.

so... if i go to B15 (00-01) Grey 259's... the mapping should stay the same, at least for a starting point, assuming i have the same fuel pressure, right? there isnt anything hidden that im missing, is there?

according to the FSM, the B15 injectors should be 13.5-17.5 ohms, and the B13 injectors are 10-14 ohms. sound right to you guys, or will i need to put resistors in it?

You should read this:
http://www.sr20-forum.com/all-motor/11825-injector-impedance.html

Also, start your own thread.

Also, you can expect to get slightly less fuel with the B15 injectors I think.

sweet thanks. if i dont get a difinitive answer on the thread you posted i'll start a new one.

and if it does go lean i'll find another route. like i said its a trial run. im not sure it will even idle. im doing all the mounting stuff on my original US highport, which has a good bottom end but what i suspect is a warped head (im thinking eventually that bottom end will get a VE head.)

So I have a question. Are these figures taking into consideration that with a boosted app the regulater will keep increasing pressure under boost? Or are these whp figures just based off the base pressure?

Cory

Just ask yourself why does the fuel presure go up when you go into boost and then you will have your answer.

it goes up because its seeing pressure, I understand that, but I was wondering if these calcs are figures before any pressure has increased the fuel pressure. I figure how often are guys running 600cc injs in an na set up that's why I was asking...