You're close.
You've got two things you need to compensate for, both the injectors and the maf. Whenever you change either one you need to change the k-value. Changing the injector size also means you need to change the TP axis. Since your not physically changing the injector, don't change the latency. Also the process on ztechz is wrong for this. Obviously changing the maf means you must change the VQ map.
Lets start with the maf, since it just means adjusting the k-value. Scaling for maf changes is pretty straightforward, you just multiply the k-value by the ratio of the two maf sizes (where I'm defining the maf "size" as the largest mass air flow it can measure in kg/cc). The trick is knowing what the maf sizes are. The Z32 maf is about 2.2 times the size of the U12/B13 maf. How do I know that? Well, thats a story for another post.
Anywho, take the stock number and multiply it by 2.2, giving you hB88D. Change your VQ map and your good to go there. You can actually do a quick check at this point as to how close your k-value really is. Burn the rom you've got at this point (Z32 VQ map, compensated k-value, U12 bin) and stick it in the car with the fuel pressure at 3-bar and the Z32 maf. Drive the car in closed loop (just drive a constant speed, when the ecu is in closed loop the o2 will flip back and forth) and watch how far the ecu adjusts the alpha feedback. Obviously you need a consult box and software for this. If its moving it more than 10% your too far off, less than that is fine. Adjust your k-value to suit.
Ok, on to injector changes. First calculate the size of the injector for 4-bar. Multiply the current size by 1.15 to give you approximatley the size at 4-bar. When I had my 370s cleaned and flow'd by RC they ended up measuring 405 after cleaning and between 370 and 405 before. 380 is probably close enough, remember the ecu will compensate for the injectors being off (but it doesn't do it on a per cylinder basis, its the average injector size) and you can adjust the fuel pressure to match as well (repeat the alpha tuning process above, but tweak fuel pressure instead of the k-value). So the size at 4-bar is approx 437cc/min. Hmmm.
Here's where life is good, guess what ecu is close enough to 437? GTi-R! Take advant age of it, switch to using that as your base rom. The advantage here is now you don't have to worry about changing the starting injection pulsewidth table, its already close enough that your car should start and idle just fine. Also, you don't have to worry about the TTPmax or TTPmin tables, they're correct too. So finish adjusting for the injector sizes: You got this right above, but use the k-value you just calculated for the Z32 maf. So hB88D x (380/437) = A07B. Tune this based on the alpha, or just tune fuel pressue, both get the same result.
Now the last part, the actual maps. You've got two problems here: first the gti-r is mapped for a larger load (TP axis) and the maps are much too aggressive for a U12 det. You've got a chioce on the load axis, you can either use the GTiR TP values and extend the U12 maps or you adjust the U12 TP scale for the change in injector size and leave it mapped to the same amount. I would adjust the TP scale for the change in injector size. You did this correctly before, but I would use 380/437 (that won't change it that much from your values).
One quick note on the TP axis: I find its easier to work with if you convert these numbers to volumetric effeciency. I'll let you smart guys figure that one out, I need someone to check my work.
Edit: The U12 bin is the most conservative stock det bin. Its very conservative. Compare the maps with the U13 bin to see where you can go and still be very safe. I'd start with the U12 maps, when your happy the car isn't going to blow up start moving everything to the U13 values.
