1988 escort gt upgrades

Looking for help on what I can do to upgrade my 1988 escort gt 1.9l ho. I am using the car in a 4 cyl. race class on a 1/3 of a mile asphalt circle track. Everything must remain stock on the car and the suspension can be upgraded as long as it mount in the factory position. Anyone have any tips on get more hp and better handling? And also does anyone know if 13 inch rims will work on the car?...thanks for your help

If everything must remain stock there's not much you can do

to make something "performance" means to replace stock pieces with performance pieces. You can' have a performance stock engine, its an oxy-moron

Wouldn't "BLUEPRINTING" be considered a performance modification? And it would still be stock wouldn't it ?