I have the MBRP race and also wanted more sound so it was obvious to me to just do 2M cat deletes. Plus I can swap the old ones back on for emissions. Now my car sounds how it looks
My approach was pretty much identical to yours. Just wanted my 22 GT to be a fun reliable daily driver with a goal of 600 whp so I went with G2+125mm. Since I never shift at redline I skipped CS/OPG, and upgraded to GT500 injectors and vortech BAP; pretty you don't need the fuel pump.
If you...
I just asked my tuner to duplicate my current tunes so now I have a normal cold start tune, a tune with 1/3 cold start, and a tune with no cold start at all
Try playing around with this calculator https://tiresize.com/wheel-offset-calculator/
1.5" is just under 40mm, and my current setup is flush with 305/35/20 on a 20x11 +50 wheel in the rear, so theoretically you'd need a 20x11 +10mm setup if that makes sense
Could be traction control kicking in? Sounds like what I experience for a split second when I try to go WOT in 1/2/3 with TC on. Have you tried it with advancetrac off?
93 should be higher than E so ~220 mpg , but also like other people have mentioned the app isn't super accurate. I have a heavy foot so it does vary a lot
BTW my shop said getting the flange welded to the old driver side cat is a massive PITA since after cutting it off from the manifold, it leaves an oval not a true 3" circle. So they had to do a bunch of fucky weldy stuff to get everything to line up.