Need help with gearing

[04hmf400]

Need gearing change to help acceleration for 150yard to 200yard drag racing. 14tooth sprocket in the front makes gearing to low. 15tooth seems to not have enough pull in 4th and 5th gears.

[sevens]

this might help
http://home.earthlink.net/~gellett/mph.htm

go up ONE tooth on the rear sprocket it is right in between a 14 and a 15 front.