I've logged my ltft's and I'm ready to make changes but, I'm not sure what cells to change. Do you try to zero all the ltft's or are there certain blocks that should be left alone?
I've logged my ltft's and I'm ready to make changes but, I'm not sure what cells to change. Do you try to zero all the ltft's or are there certain blocks that should be left alone?
Your aim should be to get between 0 and -4 in all the cells at part throttle. Then at WOT the cells in that part of the histogram should be 0. That ensures you get consistent fuel delivery at WOT.
Brian
Thanks for the answer. I didn't really state my question very well. It says in the VCM help suite. " Do not use the histogram logged corrections for cells 20,21,22". I just don't know where those cells are.
I would like to know where those cells are too. ???
2000 SS, M6, Pacesetters, TSP True Duals, LS6 Intake, FMS F12 112 LSA
I have found that it is not as easy as just using the histogram. What I have done is used the FTs (mostly STFTs) to tune the entire table. Usually you only really adjust up to about 4-4.5k RPMs...unless you turn PE off. You'll know when you see the histogram. Anyways, I have not really been paying attention to the "cells". Go over the logs after your initial tune and then focus on any "spikes", particularly during throttle transients. Something I have found is that you need to get all the high values first, and then start adjusting all the parts that need to change by about .5 each time you tune. I have seen a lot of histogram values "bleed over" onto the surrounding areas, making me adjust areas that should not have been adjusted. Ignore the cells. Make a good first run over the table, then use small increments, and watch the logs for weird spikes during transients. Your car will run better.
1998 Camaro Z28 M6: SLP Lid, Adj. Panhard, SFCs, CAGS!, Hotcam, Hooker Shorties, Katech Tensioner, Catback with Dynomax 17221 3\" Muffler, Mobil-1, Bosch +4s, 160 Stat, !EGR, !MAFless, !FRA, S3 TB
Fuel Trim Cell Definitions
0 Coast 8 Load 16 ???
1 Non-Load 9 Load 17 Idle
2 Non-Load 10 Load 18 Idle
3 Non-Load 11 Load 19 Idle
4 Non-Load 12 Load 20 Idle
5 Non-Load 13 Load 21 Coast - Deacceleration
6 Load 14 Load 22 WOT Engine Load < 100%
7 Load 15 WOT Engine Load = 100% 23 ???
0 through 15 laid out like this on Ve table.
0 1 2 3
4 5 6 7
8 9 10 11
12 13 14 15
There is no replacement for displacement?&&sure there is, its called a Blower!
That makes sense. So, you can't see the unused cells on the VE table? I get it now. Thanks.
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