I run my car at both 1/8 and 1/4 mile tracks and don't change anything including the tune up, 6:80 in the 1/8 and 10:40 in the 1/4 My car is a street and strip car, not a dedicated race car I have tried three different rear gear ratio in the car with no other changes, 3:73, 3:91 and 4.10 with the same size tires, 30 inch tall radials. car didn't vary .10 ET in the 1/4and .25 MPH between all three ratios My motor is a 4.300 stroke 400 block that is 518 C.I., low compression on pump gas motor only