i have a 521 ci around 800 hp plus 400 shot nos in a 2500 lb mud racer i now run 411 gears and 39.5 tires. what would be a better gear ratio ?, i cant get into drive till end of 200ft pit. is 620 gears to much ?. also thinking of gear drive for sollid roller cam , wich one do you recomend ? noise is not an isue