had a 255 fuel pump from an sti, 50 psi fuel pressure and rc 440. stock z6 turbo with ebay "50 trim" shooting for 9 psi but fuel running out at 4.5 psi so i put a new walbro 255 and fuel filter (one under hood) in and fuel psi dropped to 40??? under s300, to scale injectors you go to fuel trim and calculate fuel trim and put before and after fuel psi and injectors and thats how you scale them righhhtt?

 

Are you tuned?

 

ya i tuned it pretty decent to get around not trying to beat on it

 

i cranked the tables up to about 80% duty cycle at full load 7000 rpm and i was just gonna lean it out over a few pulls but its already not even rich enough, 440s are plenty for what im using them for

 

compare your spark plug readings to wideband

 

what regulator is on the car? Generaly i never change the pressures in the fuel scaling. just change from stock 240 to new 440. you also need to change the injector dead times so the behave properly with voltage changes

 

i was thinking about that but im not sure how you go by doin it, i have one of those areospeeds or something similer to blox. how do i figure out how to adjust dead times, im kinda familier with what that would do but idk where to get nmbers

 

thank u guys, but i had the same parts in my old car and it was fine but i wasnt tuning it

 

Theres your problem, those are like the ebay junks just someone put a name on it and charged more money. You would be better off with a b&m modified stock regulator or just a stock regulator. your probably loosing fuel pressure because of the regulator and having to add a ton of fuel therefore maxing out the injectors. Those regulators will work for a while then they start messing up and causing fuel spikes or drops. slap in a stock regulator and retune. If you want increased base pressure run a b series vtec regulator or just get the b&m mod kit and turn it up to 50 psi. I have been running the b&m mod for 4 years without a single problem on 50 base pressure and running 20 psi boost

As for injector dead times here is the scale

Volts.....................16.0__14.0__13.0__12.0__ 11.0___9.0__7.0
Dead Time (ms).....0.01__0.14__0.29__0.42__0.56__1.0__1.8

 

oh i wasnt aware of it being like a universal scale, i though it would be different fro certain injectors. but that what i have its the kind u cut the stock one in half, my psi at idle was 50 before i changed the pump and filter than it went to like 43. i could try a stock one, or should i pull the vacumm and leave it off ?

 

where did u find this info about dead times?

 

^^^^ Lol, he's a tuner. Wouldn't be in business very long if he told everybody how to do it. Thats why good tuners are expensive and rare.

 

That is like asking TheShodan where he found out information on turbos...

 

I had that problem too. Took about 10 dyno sessions to figure it out. Ended up being the fuel rail damper. It's on the entry side of the rail. Change it or get rid of it. Also put 2 regulators on, one on the entry side and one on the exit.

 

yeah the dead times(batt offset) isnt a universal scale, every injector is different IE rc 440's would be the same as precision 440's BUT some might be the same as those brand because there the same injector rebranded as something else. Basically it tells the injector to stay open or close a certain percentage vs. voltage they are seeing . It doesnt seem like much difference but it make a world of difference if you have the correct settings. granted you dont HAVE to set that up but it really helps in consistant driveability

 

okok sorry everyone i dont know everything about turbo-ls holy ****. but im gonna change the dead times when i get a chance. i put a stock fuel pressure regulator on and it richend up so good. so that fixed it. the its a gsr one i think, pressure is now about 60 lbs thanks