7 inches im pretty sure cuz i just measured it for rims to put slicks on. if its not 7 its 7 1/2 for sure. if u wanna find it the wheel is 9.5 inches and u measure the space from the centercap to the flat surface on the spoke and then subtract that from 9.5 im pretty sure but some1 help me out to be sure.
I special ordered 6.5 backspacing for drag rims and they fit perfectly.
I see alot of trucks with 4.5 spacing at the track (wheels hanging out past the fenders) ...suprised me how noticable 2 inches in spacing is.
Diamond Racing Wheels = 16x10 / 5x135 Avengers $135ea.
I went with Hoosier QTP 28x11.5x10 tires and forget how much I paid.
I am actually looking to purchase another set of DRW16x10 rims...tells you how pleased I am with them. For tires this time I am looking for a 30 in height, being that I am running 4.10s in the rear...plus i will have more power adders next season.
The problem in the past and still today with 16x10 rims is the availability of sizes. The sizes are rather limited. Although more manufacturers are stepping up and beginning to offer some options. I'm considering M&H 30x14.0x16LT drag tires:
DOT Certified - Wrinkle Wall
Tread Width: 10.5" Section Width: 14.0" Diameter: 30.0"
Circumference: 94.0" Rim Size: 10.0"
Code: MHD-11 Compound Type: HB-11