jetblast

first let me just say that this is my first time tuning any car and have been doing it for the last year and half. i have been using a wideband and data logging on all this time. i have seen at the tree lights about 70 times tuning for wot, and on the street for medium range engine load levels. idle has been the most challenging due to the 112 lsa i think?. anyway i have never touched the maf tables until last week and this car just woke up , the response is so much better. i went 1% encrease on the intire maf table from stock values, reduced the entire injector pulsewidth table by .5%, i was previously running it at 1.5% higher than stock and zeroed out the cat lightoff table and the ve table was encreased by 1% high load section of the map reduced by 4% in the low load section of the map and finally the pe table reduced to achieve 12.9 wot. my high oct timing table is stock on the high load section and advanced about 3 deg for the idle that's it. i'm not sure why encreasing the maf would affect performnce so much more than the ve or pulsewidth tables alone. what i do know is tha i'm consuming more fuel now but my wide band values remain at 14.68 in close loop and 12.9 wot. by the way my inj. duty cycle has ramained bassically the same at 87%. wot. sorry for the newbie story but the tuning books and even efi live maf table tells you not modify it unlless you port, remove the screen or upgrade to a bigger maf. any thoghts would be greately appreciated. mods are in my sig . thanks

99z28monster

iTrader: (3)

wow how is that newbie tuned i dont understand any of that.

SSpdDmon

iTrader: (10)

If you read the sticky that says: "READ ME FIRST"

(https://ls1tech.com/forums/pcm-diagnostics-tuning/287094-read-me-first-tuning-docs-ve-maf-ses-lights-faqs-more-01-31-07-a.html)

...you would see that you want to tune the VE table and then tune the MAF 2nd. Making general changes to the MAF table or VE table without any data to substantiate your adjustments is like throwing a dart at a dart board, while blind folded, from 100ft out and hoping to hit a bullseye. You should really invest a couple hours of reading time in there and around the forum before you do something to hurt your car.

jetblast

yeah ve table first, i know, i read a couple of books and that's what everyone agrees on, as far as hurting the engine i thought knowing your wideband and avoiding kr and a visual check of the spark plugs was key. my car has 47000 mi.

SSpdDmon

iTrader: (10)

Generally speaking, that's fine as long as you have the outcome you're looking for. People have been fudging the numbers for years with good results because they don't care about the commanded AFR matching the actual AFR.

I just wanted to clarify a little more on what you were stating. Someone may interpret it as,"Oh hey! He just made a random change to his MAF table and his car woke up! I should do the same to mine!"

slow

iTrader: (7)

I've been tuning with the maf table for years, with good results.

Ryan

jetblast

theroretically the stock ve table was engineered for the stock engine and we all know that you can rarelly achieve 100% or a bit more ve on n/a motor with the exception of some especially built engines from ground up and my modded engine is difinitely not one of them. on that note peak ve occurs at peak torque and stock max theoretical value for the ls1 is 96.231472% at 4800rpm and 29.5 and 31.0 inches of vacum, this theoretical values also of course take into account that new engines from factory vary in ve from one to another by some small margin and this new engines continue to encrease in ve performance all the way to about 20,000mi from there ve goes south and the rate depends on how hard you drive your beast. anyway since i added a head and cam package and long tubes at 9000mi on my motor my ve had changed for the better then and now should be marginally lower at 47000mi. the cam also moved the peak torque to a higher rpm colum. that been said this hole time {1.5years} i have only tinkered with ve and ifr, high oct timing table and other miscellanous tables for idle efficiency, and also have gone to the dyno to chart the progress from my mods and tuning. last week i decided to for the first time tinker with the maf table and the results were more than i have gotten from seat of the pants from any other change i have previously made, i can no longer stomp on the gas pedal and take it through its max rpm from first to say 3rd without breaking the it loose, traction control off, and it was no fun been sideways at 50mi/hr .anyways she is sucking more fuel now at the expense of better response, it just feels like i put a bigger cam or something, will be going to the dyno soon to record my progress. by the way the tuning stickies, they talk about maf first and then ve ,wrong. cheeers! and thanks for the input ryan!