world formula engine combo. Modified! Sprint kart, 335#. Non billet block and head. Race gas. No methanol. 4.43 gear for my track. Has to pull hard from 4200 to 7200. And rev to 8800 on long straight. Please feel free to leave your combo. Compression, rod length, cam, valve size, carb, header inner dia- length, No muffler. Entertainment purposes. No 10 minute motors. Endurance, 7-9 hours service before inspection. If thats possible!