trying to get LT fuel trims in line

[ssms5411]

I put in 36lb injectors today, cars running good except I'm getting 15 to 20 in my LT fuel trims. Do I just rescale the IFR table so that the car is leaner? I know so other people have put in 36lb injectors, so please respond. Also do I have to worry about the ST fuel trims? Thanks Steve

[Drone51]

have the same problem as you, gonna try to tune the ve table tommorow hope it works good we will see, ill let you know

[Nachius]

http://www.camarov6.com/ubb/ultimate...;f=35;t=000006

If you are in fact running rich across the board yes just scale down the table should be sufficient, or if it is only rich at certain points scale it down there that is the fastest way to correct it.

[Drone51]

well just tryed real quick and my car would not run for me putting the stoich to 13.0 so i threw a really rich tune on and pluged the maf in just to see how the car would act

my ltft are now a little negative instead of way positive which is what I was looking for and now I am not seeing any knock retard even when I hit 13psi on accident


I was having a problem with kr before at around 4400 rpms and up. now I think it might of been from not enough fuel but now im maxing the injectors big time. altho i did not seem to max the maf which is weird because I have maxed it at 10psi before but I did play with the maf table on this tune, I did increase the values because I pulled the maf screen out and figured if anything I rather it be richer then leaner so i increased the values some and did not end up maxing it at 5700 rpms and i swear the boost guage was 12-13psi ipw tho was at like 24ms :(


anyone wanna donate to the drone51 needs bigger injectors fund? lol

[ssms5411]

Drone51, What area did you richen it up at IFR? Or did you use PE rpm vs time. I'm trying not to touch the maf table.

[Drone51]

actully the maf table is the only table I touched that should have any effects to the ltft


i need to lean it out a tad in some places but instead of it being +10 at around idle its more like -3 to -5

I rather have the car richer then it needs to be and not have any kr


before I was getting alot of kr so far while logging I have not seen any kr with the new tune, wideband says im in the mid 10's for af at wot before I was in the lower 12's upper to mid 11's when I was seeing kr and my timing was very low


I think i could raise my advance alot now since I dont have any kr and I think the car would run better and be safer then leaner with less advance


I think I could lean it out a little bite I would like to be around 11:1 or so and im a little under that but I rather be safe


why dont you wanna mess with the maf any?


I richened wot with the pe vs rpm/time also since I messed with the maf table too so that will affect it too

right now at 11500 i have it at like 44 lb/min instead of 39lbs/min

[ May 04, 2005, 06:00 PM: Message edited by: Drone51 ]

[ssms5411]

By how much did you adjust your maf table, I'm assuming you adjust the maf by, the higher the numbers the richer and the lower the leaner correct? Today I adjusted the IFR down a little more, now my lifts are betwwen 7 and 10 at idle and my wot is between -2 and 0. So I'm trying to adjust my idle a little better. Right know I'm running 11.5 to 11.9 on my wideband but I think I'm going to lower it to around 11.1 also. It is getting alot hotter out now and with no intercooler, I don't want to risk blowing up the engine.

[Drone51]

i multiplied the whole maf table by 1.04 i did that 4 times so


you could probably just multiply the whole table by 1.08 and see how much that helps


you should not have any ltft at wot because you should be in pe mode


heck if you dont wanna mess with the whole maf table drive around not going into pe mode see what the highest hrz you hit and just multiply the values under that by say 1.08 and see how your ltft come out

my car maybe a little rich but try adjusting the table some and if you have a wide band you can see if your still at 14.7:1 like you should be while driving around when your not in pe mode if its on 14.7 and your ltft are 0 or close to that why would that not work? if your commanding 14.7 and your wide band says your at 14.7 (will fluctuate a tad on the wide band) and your ltft are at or around 0 I dont see how that is bad

right?

[Drone51]

by moding the maf table is it alot like moding the ve table anyways because the maf reading and the ve table are both used in the calculation for the af ratio


to keep it simple I would not edit both table but basicly if you edit the ve table and you add say 10 (your running lean) to a cell to get the ltft for that cell to 0, is it not the same to tell the computer that at this hrz you are flowing more air and so the computer will add more fuel to get the stoich value.


probably not the best way but we dont have all the options as the v8's do, also tried to do the sd thing and the car would not run when I set the stoich value to 12.8 or 13.0


I may try again tommorow but so far this tune I put on has been the safest tune so far for me

I would not try to tune this way with out a wide band but when it hovers around 14.7 or so when driving around it cant be that wrong, if it was it should be either reading a richer mixture or the ltft should atleast show real high negatives (i do have some negatives that I probably could fix by adjusting the maf table some and think that could fix those issues too

[ssms5411]

I adjusted the maf only at idle and it seemed to work well. I'm now seeing -4 to +4 which is alot better. Also got my A/F to about 10.9 to 11.2 which it does seem to run better. Thanks for your help Drone51. Also have you ever tried messing with the knock rate and such. What tables do I mess with and how much do I sub. or add? I was trying to get less knock showing up.

[Drone51]

is it false knock or real if its real i would not touch the kr settings


have you pulled timeing from those areas?
have you put in race gas to see if its real knock, I know you have a cam which can cause false knock but if its real then that bad.

uf you dont know when you log a run look at the histogram and look at the retard tab and right click hit load all data then set it to max it will show you where you are getting kr at and you should take advance away from there


art messed with his kr tables and basicly cut them in have or something, if you search over at hp tuners forum you can find what he did. but he did something and put his kr tables back to stock I belive.

[arthansen]

My knock was false knock. With the X-P Cam, I had so much valve noise that it thought it was knock. At first I adjusted adjusted the tables to make the reaction 1/2 and had it recover 2 times as fast.

Then I wired in a "Knock De-Sensitizing Circuit". It basically cut the signal by 35% and that was enough so the PCM no longer thought it was knock. I then went back to the stock tables.

I was running a 100 shot of nitrous at 12.0 AFR with 3* over stock spark advance with no knock.

The real answer is to have HP Tuners give us the controls over the Knock Retard they gave to the V8 guys. Then we could really make it right.

[ssms5411]

Thanks for the reply Art, I think my knock was due to lack of fuel in some areas. I think I got it worked out now. It would be nice if we had more controls like the V8's since we do pay the same price as them for the software. Also thanks again Drone51. The maf scaling worked really well.