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Having trouble tuning VE LTFT
I have a 2001 Trans Am with a 408 stroker, 625 lift / 238 dur cam, LSXR intake, 102mm TB, 100mm MAF.
I just installed NX direct port and decided to change to a colder plug before tuning for nitrous.
The motor was installed about 2 years ago. Hawks Performance did the original tune and I have driven it all this time with no issues. So with motor running fine I changed the plugs and the intake. The intake is the same model but purchased from from Nitrous Express with the direct port pre-plumbed.
After the install the tune immediately felt different. Engine struggled to idle and acceleration was not nearly as smooth. I checked vacuum and then just chalked it up to the plugs being a different heat range and decided to re-tune.
On the first scan I noticed that LTFT's were staying at zero. LTFT's had been disabled. I'm assuming they just tuned the MAF. I enabled the LTFT's and began to tune the VE.
The first few paste special % were around +/- 8 or 9 and then dropped to under 3 or 4 but as the cruising and light acceleration area improved, other areas got worse, like 12-18. And as one area got better the other got worse. I kept making adjustments but after 21 times I am basically in the same area I started.
I feel like I am missing something and was wondering if someone can look at my tunes and scans. The ones attached are about midway through.
