GMC SKI

If it were me I wouldn't wanna go near 100% on the duty cycle on the injector
Does everyone agree that that is not wise too do
why max or an injector when there are options out there like the 57lb and 60lb injectors that will work with the factory ECU

30thta436

iTrader: (10)

There is no way he is maxxing out the injector at 5300 rpm. He is probably maxing out his maf. He will max out the maf long before the the 42lb injectors. I maxed out my maf with 38lb injectors along time ago.

There is a simple solution. Do a log or live data and see what your maf reading is 5300 rpms and above.

VINCE

iTrader: (1)

Sam at Coastal mentioned your MAF could be maxed as well. Try one of these.. http://www.pro-flow.com/

BIGBOS

I say get some 60# just to be on the safe side.....

Black LS1 T/A

He already said the tuner added more fuel. How else do you guys add more fuel at WOT other than the PE/RPM table?

MYTURBOT/A

you can add all the fuel you want in the pe/rpm table but if you don`t have it ramping upward with the rpms after the MAF goes static it`ll start leaning out as the rpms go up. IMO if the injectors were maxed the A/F graph would overlay itself after 5000rpm but it don`t it`s a little richer across the board.

Black LS1 T/A

How do you account for the fact that I gave out of MAF freq at 4800 RPMs, yet kept less than 12:1 A/F ratio up to 6000 RPMs?

We use the PE/RPM table to tune A/F. Any other way, with our stock computer, can't be very effective.

MYTURBOT/A

You rescaled your MAF table or your compensating by ramping the pe/rpm table.

MIGHTYMOUSE

iTrader: (59)

the 42's are close anyhow.. change them out (yes i reccomend my 60's)
and make sure the guy knows how to use the PE table..


at the rpm the maf stops increasing you need to have your PE curve move up exponentially to fuel the increasing rpm and boost.

send me the .ls1 file and ill look at/fix it

you could also move the base FP up 10psi or so and squeeze a bit more from them.

White_Hawk

iTrader: (3)

I saw a guy in my car club make 600 rwhp on a dynojet with a single in tank pump and a rising rate setup from a 97 vette. I think there is something else causing you to go lean, because he was running the same injectors and with the rising rate he was up at about 75 psi (a little less than you). Bigger injectors definitely wouldn't hurt, though.

-Geoff

Black LS1 T/A

Uh.. yeah! I just SAID use the PE/RPM table; THAT is how you adjust your A/F ratio for WOT!

Black LS1 T/A

If his pressure is good and he is commanding the injectors to use the fuel that is there, and it goes lean, what ELSE can it be but not enough injector?

You need to get EFILive or Autotap on that car to put the issue to rest.

Also, if the Tuner couldn't get EFILive to work on your car, I'd question the tuner's skill in this area.

bonecrusherz06

Call andy at a&a, he helped me with my 03 z06 with the side mounted module. do you have long tube headers and x-pipe? and maybe some head work you want max airflow as well as fuel.

CAT3

iTrader: (9)

I am by far not an expert, but I would ask the tuner about the MAf after the 5000rpm line where your power drops and fuel too! If the MAF max is being compensated for, then get some injectors. Doesnt seem right to max out 42's at that low RPM vs HP.

01Bird_of_Prey

UPDATE The Tuner got the EFI working and said that there was a Glich in the program. The data did not store, that's why the second run was leaner. We re-tuned on the street with a wideband. The first run computer untouched was 80% duty Cycle and too lean like the chart shows. Made the correction, he made it super rich 10/1 air fuel @ 110 Duty cycle, so he backed that off to 11.5/1 AF @ 104 Duty cycle. So everything seems to be fine. Thanks for all the advice. Will Dyno soon again to see what the numbers are.

BlwnTA

iTrader: (18)

Still learning on the PCM editing side. But food for thought...I made 587rwhp with 42.5's and A/F was barely in the 11's on a Dynojet. But I do understand 42.5's are only good to about 600 rwhp so the first step in solving the problem is obvious.

Mark

Black LS1 T/A

I wouldn't say 104% Inj Duty Cycle is "fine". You can do it for a while, but you are beating the injectors to death. You need bigger injectors.