HB pro 2
777 rear arms fit this car and let the wheel base be adjusted from 12.50in to 13.25 in. The stock arms flex to much in the rear and only let the wheel base go from 12.50in to 12.75in. My cars set up is good with 13.1 at the track in reedsburg and the rock pile.
Also a wide range of (hop ups and stock) 777 parts fit these cars.