bolt-on tuning: STFT/LTFT
bolt-on tuning: STFT/LTFT Hey all, this is kind of an extension of a thread I started earlier that kind of drifted to other topics. But I have a question regarding bolt-on-only tuning and where that would typically put my fuel trim values when I logged my vehicle. I plan on tuning with HPTuners as soon as I do my pulley sometime this week and contact natronathon and get something set up, but I do have access to autotap now and my logs show what I think are outlandish fuel trim values.
My worst trims come in the deceleration fuel trim cell (I want to say 6 but I can't remember off the top of my head) where I show a constant -25 LTFT and short trims generally in the low -20's up to a max of -23.8. So adding this together (as I understand this is what determines the total fuel trim) would put me somewhere upwards of -48....most trims are better looking but still generally combine to be around -25
Those numbers just seem a little high for only bolt-ons. I've done just the airflow mods and that's it: lid, ram-type setup, p/p throttle body, ls6 intake, headers, catback. But to have a trim that's 48% off, now that seems steep. I've got logs from back before I went mod-crazy (I think I only had a lid at the time) and the trims are still pretty respectable. I've also noticed a few cells of my new logs where the timing shot as low as -2 degrees advance. It just seems messed up. I'm wondering if this is truly where I'm at or if anything is wrong with my tuning, sensors, or the autotap program in general. I'd be more than happy to send anyone the atap logs that wants to look at them. Thanks for anyone who replies.
My worst trims come in the deceleration fuel trim cell (I want to say 6 but I can't remember off the top of my head) where I show a constant -25 LTFT and short trims generally in the low -20's up to a max of -23.8. So adding this together (as I understand this is what determines the total fuel trim) would put me somewhere upwards of -48....most trims are better looking but still generally combine to be around -25
Those numbers just seem a little high for only bolt-ons. I've done just the airflow mods and that's it: lid, ram-type setup, p/p throttle body, ls6 intake, headers, catback. But to have a trim that's 48% off, now that seems steep. I've got logs from back before I went mod-crazy (I think I only had a lid at the time) and the trims are still pretty respectable. I've also noticed a few cells of my new logs where the timing shot as low as -2 degrees advance. It just seems messed up. I'm wondering if this is truly where I'm at or if anything is wrong with my tuning, sensors, or the autotap program in general. I'd be more than happy to send anyone the atap logs that wants to look at them. Thanks for anyone who replies.
Last edited by rush7; May 30, 2005 at 08:59 PM.
