Alright, I'd like to hear opinions.

I've heard 2 trains of thought.

PRJ: Switch to the K-box

Phila: K-box software is requires too many tweaks to work (properly) with the NA s4 hardware, Stick with the M-box and convert to a 16 bit axis.

I'd like to know more. In using an 8 bit axis we're limited to 191.25 given the conversion factor (FF=255, 255*.75=191.25). A 16 bit axis doesn't have this problem. Since pretty much everyone here is exceeding 191.25, what're you guys doing? I've yet to see a file uploaded that's had the axis' modified. I assume underscaling the MAF's so that max load is roughly 191.25 and working with that? I've seen files with proper MAF scaling (not underscaled) that threw P1557 codes when hitting boost despite no leaks. I assume that's the ecu reacting to the extreme loads. Can someone elaborate on this, or point me in the right direction?

To be honest, I'd love to hear how you guys are running properly (not under) scaled mafs without hitting these restrictions. I've been contemplating switching over to me7.1.1 primarily for these reasons.

All constructive criticism/commentary is welcome. If this is going to turn into an argument, or be filled with condescension, I'd just as soon have it ignored to be honest.

Well search as I might, I've yet to find anything that I felt adequately explored this.



The debate is what I'm interested in. There's more than one way to skin a cat, but thus far all that I've seen discussed (and not in detail) is MAF scaling to alter the load the ecu sees. I know there are guys on here that are surpassing these limits.

In general (assuming the hardware is 100%), positive deviation is the result of rlmax being too high at low rpms, not from any rl limit. I'd have to see a log to know for sure.

http://s4wiki.com/wiki/Tuning#Positive_deviation

The lookup itself is there; it just isn't being used in some cases where rl was choosen vice rl_w (obviously).

I think I like my alternate plan better though

Once I get fully back up and running, I will incorporate this with the completion of the 5120.