Can anyone tell by my data log if I would benefit from a dyno tune?
01-24-2009, 09:12 PM
#22
01-25-2009, 08:14 AM
#24
How's he going to calibrate the MAF table without 'em? I realize that the MAF is disconnected while autoVE. However, proper MAF calibration, afterward needs the sensors.
01-25-2009, 01:48 PM
#25
TECH Fanatic
Join Date: Feb 2004
Location: Lexington, KY
Posts: 1,259
Likes: 0
Received 0 Likes
on
0 Posts
Don't you still leave it in open loop when tuning the MAF so trims aren't adjusting while tuning the MAF? I believe he could use the factory bung fine, I would just recommend disabling the trims before removing the factory 02. And don't re-enable trims until fuel tuning is complete and the factory 02 is back in place.
01-25-2009, 03:54 PM
#26
^^^
You need the trims to tune the MAF table. 0 to -3% STFT @ idle. He will also benefit by somewhat tuning the idle prio to pulling the MAF for autoVE because it is possible that if he doesn't, it may not hold an idle after auto VE.
I agree w/ FROST & you in that it can go in one of the stock bung ports for an experienced tuner of whom knows what to expect & can easily tune a MAF table & idle afterward. I was stating what is better for a new tuner that will result in the easiest method. Even his friend w/ HP tuners must be new to tuning because he (his friend) has not realized the need for a wide band.
You need the trims to tune the MAF table. 0 to -3% STFT @ idle. He will also benefit by somewhat tuning the idle prio to pulling the MAF for autoVE because it is possible that if he doesn't, it may not hold an idle after auto VE.
I agree w/ FROST & you in that it can go in one of the stock bung ports for an experienced tuner of whom knows what to expect & can easily tune a MAF table & idle afterward. I was stating what is better for a new tuner that will result in the easiest method. Even his friend w/ HP tuners must be new to tuning because he (his friend) has not realized the need for a wide band.
01-25-2009, 04:38 PM
#27
TECH Fanatic
Join Date: Feb 2004
Location: Lexington, KY
Posts: 1,259
Likes: 0
Received 0 Likes
on
0 Posts
Interesting. When I tuned my MAF I had it in open loop so that nothing else was influencing the fueling other than the VE and MAF. But I've since removed the MAF so it doesn't much matter now.
But yeah it sounds like they are pretty new to tuning. Wideband is a must have.
But yeah it sounds like they are pretty new to tuning. Wideband is a must have.
01-25-2009, 05:36 PM
#28
Tuning in open loop, with the wideband in an upstream bung, you use the wideband correction % instead of fuel trim % to dial in either the VE or MAF.
As for the duty cycle being so high, it may be that it's so rich (10:1) that by the time you get it tuned (WOT) the DC my come way down. It's only when you've got the WOT A/F dialed in to roughly 13:1 that you need to worry about the inj DC.
As for the duty cycle being so high, it may be that it's so rich (10:1) that by the time you get it tuned (WOT) the DC my come way down. It's only when you've got the WOT A/F dialed in to roughly 13:1 that you need to worry about the inj DC.
01-25-2009, 05:37 PM
#29
He said he got the software in August. He's only used it on his GTP from what I gather. I was under the impression after talking to him you could tell more about the a/f even without a wideband just obviously not anywhere near as well
he said the car seemed very rich at idle, good under normal driving, and somewhat rich up top
his software showed my car at 24degrees timing WOT, and with occasional kr though...on my snap on 2500 it shows my wot timing at 29 degrees, if anyone has a clue what that's about
he said the car seemed very rich at idle, good under normal driving, and somewhat rich up top
his software showed my car at 24degrees timing WOT, and with occasional kr though...on my snap on 2500 it shows my wot timing at 29 degrees, if anyone has a clue what that's about
01-25-2009, 05:41 PM
#30
I've got my dad asking around (he knows a lot of racers back home) if anyone might have a wideband I could borrow for a day or 2. I know I always smell like fuel after driving a bit and it takes no time at all for the car to make your eyes water idling in the shop back home. No smoke or anything from the pipes though and fuel mileage at cruise is a nice 24-25 mpg.
I can't afford to even help buy one right now, but at the same time it's my daily driver car so I'd like to make sure everything is safe especially since they say running injectors that high can cause them to fail quickly. Until then I'll just avoid WOT runs at all.
I can't afford to even help buy one right now, but at the same time it's my daily driver car so I'd like to make sure everything is safe especially since they say running injectors that high can cause them to fail quickly. Until then I'll just avoid WOT runs at all.
01-25-2009, 08:23 PM
#31
The same way you have to calibrate the rest of the MAF table (not just down low); using AFR % error against the airflow values in the MAF frequency table. You can only tune a very narrow range of the MAF table with trims. Since you have to do most of it with the wideband, seems pointless to not do it all. And as I said, since you have to be in OL anyway...
01-26-2009, 06:34 PM
#32
The same way you have to calibrate the rest of the MAF table (not just down low); using AFR % error against the airflow values in the MAF frequency table. You can only tune a very narrow range of the MAF table with trims. Since you have to do most of it with the wideband, seems pointless to not do it all. And as I said, since you have to be in OL anyway...
You're right. I stand corrected. Was trying to lead them to an easy method & in doing so neglected many details. Thanks
