Professionally built I purchased this motor when i bought out another racer, he had no info. I had the motor professionally inspected. I have ran it, it has great smooth power methanol, currently running as imca open Specs: Dart Iron Eagle 215 heads 1.5 usa red rockers After market crank Billet main center caps - Arp bolts 6" H-beam rods - Arp bolts Double roller chain Icon .030 pistons Melling oil pump 400 dampner Pan to Intake $3700 includes water pump, billet dist and flex plate. Currently in car so you can hear it run and check gauges. 715-377-7694