LS1/LS2/LS3/LS4/LS7 etc. - LOGGING, ADJUSTING INJECTOR SLOPE

[gdragich]

well, your RPM's are on the low side... but based on this log, adjust your injector slope to -6% and you should be good to go....

I know and that was going up to 70 on the freeway! I mean if that's what it cruises at-guess thats how they have the Denali's geared. I'll make the injector adjustment and give it some time to adjust. Her tail pipe always seems to show rich condition, so I suspected it needed to be toned down.
Maybe adjust the program to read a little lower 1500/1600 as one of the parameters. Probably are others of us out there with same.

Thanks!!

[steeleshark2]

Go down one gear and drive at 1900-2000rpm.

[steeleshark2]

Bump!!

[jlosh20s]

Hello guys i have a 2001 tahoe with a 5.3 with a magnacharger radix 112 with 3'' pulley running 12lbs of boost at WOT with LT headers high flow cats,x pipe and dual magnaflows oh and it has 42lb injectors.My problem is that i currently have been receiving my tunes from nelson performance and we cant seem to get enough fuel in my 1st and second gear it runs about 13.5-14.0 and when i get to third it will be about 12.5 and in fourth it will go really rich about 10.5 i am currently on my i think 8th tune and we still cant seem to get the ecm to go into PE mode quick enough atleast thats what im being told the problem is oh and at WOT i have 65psi fuel pressure any suggestions??

[06MonteSS]

you're getting enough fuel from the stock fuel pump??

what were the stock injector sizes? your new injectors aren't maxed out, right? what's the injector duty cycle at when you're logging it?? the injector's duty cycle shouldn't be any higher than 75-80%...


as for the tune itself, check these:

under Table > Fuel Calibration, did they adjust the PE Cold Threshold and PE Hot Threshold throttle positions??

stock settings are that you have to be at 90% throttle before the pcm allows the PE mode to kick in... but in your tune, you should have them set to 55% from 1600-2400 rpm, and then 45% for all the rest... if they are already set to these numbers, try setting them a little lower to make the PE fueling kick in sooner...

also, in Scalars > Fuel Calibration---- PE Delay bypass RPM should be set to about 2800-3000 rpm... PE Enrichment Delay should be set to 0 sec....

[jlosh20s]

i have two fuel pumps stock and a walbro 255 inline 48 at idle 65 at WOT i dont know what size the stockers were i think think there 26lb's also how do i look at injector duty cycle havent seen it while logging and the person i got the charger from was running the same pulley and the same injectors on a 6.0 with no issue so i dont see why they wouldnt work on a 5.3 and ill check the other stuff out now

[06MonteSS]

you'll need to log the rpms, injector pulse width, and whatever else you want to, and then when you export the log from the dataviewer to a csv file, you'll need to apply a formula to the pulse width & rpm data to get the duty cycle numbers...

here are some calculators where you input the rpm and the pulse width numbers, and it will tell you the duty cycle...

http://www.stealth316.com/2-calc-idc.htm

[jlosh20s]

im not seeing an injector pulse width on the tool?

[jlosh20s]

im assuming that ltft's for a supercharged vehicle are different? At 1914rpms my ltft is at 22.66 bank 1 and 25.00 for bank 2

[06MonteSS]

hmmm... not sure... but I wouldn't think so, since at part-throttle normal driving/cruising, you're S/C shouldn't be running, providing any boost anyway....

are you doing the tune adjustments right at nelson, or are you just doing things through email tunes with them?

[jlosh20s]

email tunes but its been 2 months and still not running right

[jlosh20s]

just logged again at 55 at 1900 rpms bank 1 is 4.688 and bank 2 is at 9.375 dont remember what that other log was from but this data is from right now

[06MonteSS]

k, well that's a lot better and different than the 20-25's you mentioned before heh...

I would go -6% on your injector slope setting...

as for the WOT AFR, are you using a wideband O2 sensor in your truck to get that??

and what are you using to data log - the predator itself, or a laptop and the dataviewer?

the pulse width is in there somewhere... check the full complete parameter list on the predator, and/or in the dataviewer, check under the infrequently used PID list, or any other lists there are...

[jlosh20s]

yes i have a autometer wide band and im using my laptop to log with the dataviewer

[06MonteSS]

k... well, check through all the lists of DMR's, infrequently used PID's, etc etc... the injector parameters are in there SOMEwhere...