Thread: Ok here is my dyno. Why aren't these the numbers I should be getting?

also, i forgot to mention. when we were drivng around scanning and tuning my car PRJ told me that the 1-2 shift on the transmission was shifting slow. it was supposed to shift in .24 seconds but it was shifting in .52 seconds. he told me once it reaches .64 seconds or something it would set a code. You can feel it slip slightly during normal driving too. its not bad and some people wouldnt even notice it but its there.

im not going to get around to scanning til tommorow. what should my 02's, and STFT and LTFT be reading at? what other things should i be watching at what should their numbers be reading?

thanks everyone for the input so far.

I say drop the pan and see if there is something in there...shifting that long doesn't sound good...who tuned your car?

PRJ Performance. Hes in Morristown, IN. He only works on and tunes the 3800.

Scaling the MAF is the best way to do it and get repeated results. Adjusting the base AFR in PE mode won't give you the same results in every situation, since its affected by the RPMvsTime table.

OK hooked up the autotap tonight. results are a lot different then they were 1.5 months ago, thats for sure.

Most of these reading were taken during 20mph-75mph WOT runs:

A/F Ratio:
Idle - 14.7 : 1
WOT - Started at 11.7 and worked its way down to and locked in at 10.6 : 1

KR:
Sporatic blips. Mostly around 1.9 -3 range. Readings has high as 12.6 would randomly pop up for a second then go away.

Timing:
Locked in at 15.5. Saw timing jump up to 36.5 at during normal driving a lot.

LTFT: Locked in at -12.5. Under normal driving locked in at -3.9

STFT: Locked in at 0. Under normal driving saw -5.0 thru 0.

MAP: 46.5-50 Hg

Throttle Position Angle: Locked in at 99.6

Misfires Occuring: I kept seeing 147 popping up every 5-6 seconds.

02 Sensor Bank 1 Sensor 1 %: 45
02 Sensor Bank 1 Sensor 2 %: 50

MAF Rate: .64 lb/min

Misfires on indvidual cylinders: every individual cylinder was missfiring every so often. Saw 15-55 on and off on every cylinder.

Hopefully I got all/most of the reading i should have taken.

How did all the reading change like that in the past month? When it was getting tuned it was set at 20* timing. The only KR i would see is a blip of 0.2 at the 3-4 shift. and fuel trims were set at as close to zero as possible. i think i remember him telling me one of them was at zero and the other was at -10 but he got it to -2. I don't understand why everythings different now.

If your LTFT locked at -12.5 during WOT something is seriously wrong somewhere. The tune is way off.

that is WAAAYYY too rich. and youre knocking.

i now see why your power level seems low because it is.

ahhh geez. so basically theres something wrong with my car that is

A. not throwing any codes and
B. threw my tune totally off

???

I have a feeling this is aboout to be a pain to figure out.

Originally Posted by 04CompG

ahhh geez. so basically theres something wrong with my car that is

A. not throwing any codes and
B. threw my tune totally off

???

I have a feeling this is aboout to be a pain to figure out.

or your tune is just way off. when did PRJ tune the car? over winter? there is your problem if so. in the cold air youll get more timing and more boost, so you need fuel to compensate.

he tuned it 1.5 months ago. i dont remember the temp but it was probably around 52 degrees.

i had been using the autotap to scan for KR all along (before PRJ) after prj and i had 0KR. (5-7KR stock).

While PRJ was tuning there was only the one blip of KR (0.2) during one of my shifts. And i remember him telling me my fuel trims where at like -10 and after a few minutes of tuning he got it pretty close to 0.

looks like you need another tune. weather changes so the fuel trims change.

alright talked to PRJ today. going to schedule the retune. i probably wont be able to make it down there for 3 weeks though. might be able to do it in 2 weeks, not sure yet. we may even hook up the wideband.

(crap why do i feel the need to get headers right now?!?!)

Ok went to PRJ this past weekend. I put the MAF sensor on backwards some time ago and it caused my tune to go haywire

but on the bright side we hooked up the wideband and retuned. car runs the best it has ever ran. its so damn smooth and fun to drive. i'll be going back to the track and getting another dyno sometime this summer.

Its always something small like that...hey when I installed my rockers I didn't bolt down the harness that runs into the ICM all the way so everytime I'd get on it the lights would dim out and it would misfire like crazy