I put a 18 Briggs opposed twin in my Hyundai and it scats , according to the radar unit in my son's patrol car on a paved road it will pull right near 38 mph, has enough torque to spin the tires when on dirt ( 20 inch tires ) cranks and runs great. I had to do a ton of fab work to get it in tho. I would have used a V twin if I had not had the old 18 already and it was running sweet before I started.