I think a 1521 in a truggy would be undergeared at only 40mph, unless a lower kv like 1200 were chosen. Otherwise, the other suggestions would do just fine
SH Z-Car, Custom Crawler, 8s Savage, 12s XTM XLB 1/7 buggy, 4wd 4-link rear/IFS Pro4 truck, Custom Hyper 10 Short Course, Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz