well my LTFT's are all over the place when the car is running, it is to my understanding that if a car is tuned right the LTFT's should be pretty consistant and closer to 0. I logged the car on a ride to a friends house(about 30 min ride). Filled in as many cells on the Histogram VE-LTFT table. and took the values recorded, and added or subtracted the values exactly from the VE table. For example, i had -1 at 2.0/15kpa. So i subtracted that on the primary VE table. Is that the correct way to change it? I also got 9 at 56/95kpa so i added 9 onto the VE table at that spot. I just ran it again and the LTFTs werent that much better, in some spots they were worse? was it because i didnt reset the LTFTs? or is there a multiplier for calculation what the VE cells should be based on a logged cell. Please help, thanks

 

If you are truly in SD and not using a custom OS, your changes need to go into the secondary VE table, since that is what is being used when the MAF has been failed.

 

It might be to your benefit to post your most recent log and your tune, this will allow us to help you a little better.

 

well i wasnt running it in SD mode, i just learned that i should have been though. (just got word tonight on my comp, so i can read the tuning 101 guide). But none the less, if you guys would wanna take a look at my tune/log i would really really appreciate it. edit: ive been trying to upload them but it says i exceed the quota size?

 

I am sure that you will not have any trouble getting help as long as you are specific about the issue you ned help with. Make sure you read the tuning guide before posting any logs and tune as we will not be able to help you if your tune is stock. When moddifing your VE tables in SD mode make sure you follow Frost advice and make the changes to the Secondary VE table as you will not notice any change in fuel trims if you modify the Primary VE table if you are in SD mode. Good luck tuning and have fun in the process.

 

Thanks man, i appreciate the tips guys! i have one more thing to ask.. and i know i must sound like an idiot, but when i have the secondary VE table setup in SD mode, can i just copy that field over to the primary, hook the MAF back up and on HP tuners is there a simple copy/Paste function? Im new to all of this so i really appreciate your patience, thanks again guys

 

Make sure that you add the LTFT to the STFT. This will give you what the correction should be. you will need to tune for the MAF. You know to tune full thorttle u have to have a wideband o2.

 

For wide open i was going to tune via the 02's(narrowband). In the Tuning 101 guide it says that the 02 voltage around 3600 should be .800-.900 i was going to try and get that through the wot table?

 

The LTFT's are percentage not an absolute. In your example, you would have subtracted 1% of what was in the VE table not subtracted 1. After you do this, then you copy the appropriate VE table entries to the secondary VE table.

Reb

 

so i would have taken .01 from 10 for example, and put that new value in?

 

You can't copy secondary to primary straight off,
you need to build the more detailed primary by some
method (I've built Excel 'sheets to do the "missing"
lines by interpolation, I'm sure others have too).

If your LTFTs move a lot across a drive cycle, have
you revised the FTC boundaries to more finely divide
the space you really care about, and get them all
in play and mostly in the areas where trimming is
most useful?

 

The easiest way is to copy from your log and then do a paste special multiply by %. There is even one that will let you paste special multiply by % half when you start getting real close to to what you want so that you do not over shoot.

Reb

 

Just a simple question and you dont have to answer if you dont want to. Im looking at your mods and im wondering why are running SD anyway. I really dont see a need for it in your application.

 

Better get a wide band. There is alot of data that says that NB can be way off. You can hurt your engine faster than you think. You should go with a custom OS then you will not have the secondary table. AS I said, you need to add the STFT to the LTFt to get you correction. Then do the mult by half thing.