This past weekend i got back to doing groove to my 03 gmc Denali. I checked the depth and angle. I even took it further and shaped the tb plate like I saw on one of Ron's videos on youtube. I also noticed on my tb that is hump or ridge from the factory behind where you do the groove. I used the same shaping tool to smooth out the transition so the wave form does not get affected.Look at my pictures and you can see the hump is about the length of the groove sharp edge on both sides. I am going to do a relearn and conditioning asap. I could not do it same day because I got this nasty cold and my kids got it too. I will update you with mpg and all the good stuff soon. It idles great, dryer smelling exhaust , and feels responsive.
