Highlander:
For my own curiosity,
What kind of injectors are you running? 50#?
What PSI of fuel are you currently running?

Thanks,

 

8 30# svo's
2 90#MSD's and 1 34.8 siemens (theese are on the superfuelers)

PSI should be 43

I have no problem with fuel as I have been able to get to lower than 10:1 AFR at 6krpm

 

Good to know....I thougth that you might be running out of fuel with the Air fuel ratio going upto 12.6 to 1 but thats good to know that I shouldn't have any problems running the same Walboro pump and 50# injectors on the rail to achieve the same results as you are getting.

Thangs again,

 

I do have a lightly heavier cam though... I prefer the route of the 30s and superfueler because its easier to get better gas mileage...

As of right now I am doing about 7 mpg....

I will be changing to speed density today to see if it aids a bit of a problem that I might have with the intake... I was maxing out my maf in the beginning at 9psi and now the most I was getting was 441g/s so there may be some air comming via somewhere else rather than the MAF...

I will try and rich it up more and see if I can advance a bit more to get to the 500rwhp

 

Its possible.. did them today!!!!

501rwhp!!!


Now onto the bad news... the car doesn't feel as a 500rwhp car...


I raced my father on his z06 and I couldn't beat him..heck.. he has 360rwhp....

Damn

The gig??? Well.. I uninstalled one of my O2 sensors to install the wideband... and the car ran in open loop... hence how I tuned it... now.. the car is running in close loop and its not performing.. anyone got an idea??? Shouldn't the car run by tables??? It has happened to me twice with 2 different cars.. the car will not run the same in open loop as closed loop... WHY?

 

Out of curiosity again

Where you still only using your Walboro 255 intank pump only?
And did the car run lean at all while trying to achieve 501HP?

Thank,

 

Are you putting the power to the ground? In other words, have you done anything to the suspension? I ran door to door w/ a Z06 a half dozen times w/ just the Procharger, Metcos and ET Streets.

 

I was in third, I didn't want to race, I double clutched to 2nd and slipped... i had to let go... and started again and then missed 3rd.. but the car wasn't running quite as it should because:

To measure the AFR on the dyno I had to disconnect one my O2 sensors and the tunning was done in open loop.. on the street.. there was no tune, because the O2 come back in and the car is in closed loop and a different table is used.

I changed gasoline and finally was able to hit better timing with higher heat...

Another thing though.... I did the 501 with the car cooled down... IATs were 120 at full boost, as opposed to 487 when they were 170-180

 

Judging by your description of MAF readings and experience with open vs. closed loop, I'd say that you have an air leak after the MAF.

You see, the BLM will change to compensate for an air leak. These computers will adjust your WOT injector pulsewidth based on the BLM at part throttle. In other words, if your BLM is anything other than 128, then the computer is changing your fuel settings while at full throttle in closed loop.

You can either fix the leak or lock the BLM on 128 using LT1Edit or TunerCAT.

I had an exhaust leak that caused a similar condition in my car. My left BLM was 128, and right was 144.

Mike

 

I fixed that.,.. it was an air leak...

Now I have a huge problem!!!!

After 5400rpm the AFR will climb no matter what I do... am I maxing my injectors or is it that I after reaching the 471gps?

 

When I turn off my superfueler, my A/F ratio climbs after the MAF maxes out (about 5200 rpm). So, any additional fuel the engine needs after the MAF maxes is supplied by the superfueler.

Essentially, my superfueler does nothing until the boost passes 8 psi.

Either your superfueler isn't adjusted properly or your fuel pressure is dropping off.

Mike

 

Well... That remains to be seen.. my superfueler is set up to produce after 7psi...

I have it MAXED OUT at 9-10 psi!!!!

I have 2 90s and 1 34.8 which I will substitute for another 90.

Let me know what you think...

 

According to my calculations, your 8 - 30's, 1 - 35, and 2 - 90's will support over 600 rwhp easily, so you have enough injector.

If the superfueler is on max, then the 8 main injectors must not supplying their rated fuel flow. This could be due to either not enough fuel pressure, or the computer not telling them to increase pulse width. I can think of the following things to check/try:

1) Check the fuel pressure under boost at high rpm.

2) Check the tach wire to the superfueler to make sure it's hooked up.

3) If 1 and 2 are OK, then go into the computer using LT1Edit or TunerCAT and adjust the PE table upward where you're experiencing the lean condition. This will increase main injector pulse width and richen the mixture.

Mike

 

I will check the fuel pressure under boost.. I have a racetronix fuel pump with the harness I have the high pressure.. I have the fuel pressure set at 55psi... Any other suggestions??? I have a flatline at 12.5 but when I max out the maf it will go up no matter what.. I have the PE tables already at 50 with tunercat...

Let me know.. I have seen on datamaster 150% duty cycle anyways.. maybe the bigger injectors are not flowing what they need... when I had 393rwhp I had 3 34.8 siemens up top and they were maxed out...

 

Sounds like you need some 42's and to start adjusting your VE tables...

Jack
Racetronix