4.8l 13.5 PSI: Tuning, IAT/Intercooler, 1/4mile time question
#11
TECH Apprentice
did you log timing? my friend has a na l33 s10 with stock l33 timing tables and it was pulling like 9* at 130* iats. his timing at wot was between 3 and 5 degrees for the whole pass.
#12
Thanks guy, I appreciate the input. I'm pretty sure timing and AFR is the #1 culprit, and timing number #2 the more I research and look at the logs.
I'll do some research, but what are tell tale signs that my backpressure is becoming an increasing issue/concern? Kyle you're correct, 76mm magnum.
One day the hi-ram wont be enough for my set up! One day, very far in the future HA. It looks awesome and I don't like to do things twice. I know its hurting me down low, but should be helping up top some point soon...
George, appreciate your wisdom and advice as always!
Yes, I logged timing. Lowest it dropped was to 11* due to IAT table pulling 1* from the commanded 12*.
I attached the log, tune, and config if anyone would like to take a look.
I'll post up some new results after Friday night.
I'll do some research, but what are tell tale signs that my backpressure is becoming an increasing issue/concern? Kyle you're correct, 76mm magnum.
One day the hi-ram wont be enough for my set up! One day, very far in the future HA. It looks awesome and I don't like to do things twice. I know its hurting me down low, but should be helping up top some point soon...
George, appreciate your wisdom and advice as always!
Yes, I logged timing. Lowest it dropped was to 11* due to IAT table pulling 1* from the commanded 12*.
I attached the log, tune, and config if anyone would like to take a look.
I'll post up some new results after Friday night.
#13
I personally think the mph is a bit low. Is it just shifting to third at the end of the run? How do you know the 3-4 clutch isn't slipping? Your Sig only says vette servo. Do you still have all the torque management in it?
#16
What fastjweb said, I have an out of date sig. Now have a 4l80e, hd2 transgo shift kit, 3.42's, and a 28" tall tire. Shifting out of 2nd at 6900rpm which is 114mph. Gears aren't ideal, that's for sure. Its hard to do any 3rd gear WOT tuning on the street.
I also want to look into the offset for my AEM Uego...recently I noticed that the HPTuners seemed to reflect an AFR reading about .3 leaner than what the gauge was reading. If that's the case, then my whole map could be .3 too rich. Havent gotten a chance to look into that yet
#17
If you're still Running the Isky Triple 12, why are you running it so high of rpm? That is not a top end cam. . At 6k that thing is probably done. Why don't you let it shift at 6k and see what happens. If the power is falling off up top it's not going to gain much mph. Let the torque of the cam / turbo set up actually work for you. Get some meth injection and give it 5 or six more degrees if timing, it should be a beast.
#18
So, I made it to the track tonight. Had some interesting results including a new PB of 12.05sec@112.81mph w/1.78sec 60ft. Ran three 12.05sec quarter miles...the timeslips are almost identical. Did the math based on the tune and I'm at 35% converter slip which explains a lot. Each of the 3 passes was on 13 degrees and 13.5psi or so. 1st two passes I left at 8psi on the 2 step at 3400 rpm, 3rd pass I left on about 12psi on the 2 step at 3600 rpm which did not result in any quicker of a 60ft time.
So new PB but need to figure out the converter. I'll get up with Circle D and see what they suggest. I attached the current log, tune, and config if anyone is interested. Thanks for looking and all of the help!
J
So new PB but need to figure out the converter. I'll get up with Circle D and see what they suggest. I attached the current log, tune, and config if anyone is interested. Thanks for looking and all of the help!
J