I run a brake in mine, 580hp small block 416 with 10 inch tires, with no problems, but it is snaky out of the hole, going to put 12.5 tire on it next time out, witch i hope is next year, money and time permits. I run 1/4 mile @ 10.30 @ 130 miles, my best 60 foot is 1.45 on s/s springs. after 200 passes is i broke one tooth off the ring gear.