REFLASHING USING ( STFT LTFT )

hello , how are you all , in the re flashing course , Andre mentioned that some tuners use the ( LTFT and STFT ) to rescal the maf and the speed density table , i want to know how , in case of no wide band output connected .

thank you .

Mosto,

I tend to turn off the LTFT and will tune off STFT, although this will only work when the engine is in closed loop control and not WOT.

If you set up a histogram using rpm vs load (map, g/s etc) on the axis vs STFT you should be able to map your STFT percentage correction then you can use this to know what corrections you need to apply to your speed density map.

In some reflashing software you can even highlight your stft correction histogram then "copy" and then apply a "special paste" to your VE map which will multiply your VE table by the STFT values for you.

thank you Chris for your support , i really appreciate your valuable info , and do you prefer disabling the maff sensor and setting it to zero , and always tune on the speed density ?

best regards

What is the vehicle you're tuning and what software?

Will help me explain a bit better depending what you're using.

Also are you wanting to tune full speed density, blended or if you're tuning something like a evo or subaru which has an afr table and maf table

Its my first time reflashing , am using the vcm pro suit mpvi

For a near standard car (Holden/GM) I will set me PE values to what I want to target under WOT then log and trim my MAF table.

You can then move onto full speed density and also a blend of the 2 which is how it works from factory

Check out these 2 webinars to start and if you have any questions let me know.

https://www.hpacademy.com/previous-webinars/099-maf-rescaling-with-hp-tuners/

https://www.hpacademy.com/previous-webinars/optimising-full-power-fuel-delivery-gm-ls3-e38-pcm-hp-tuners/