cobmustang3.8

i got a 98 stang with custom exhaust and vortex mufflers and i wanted to know what could make it louder without cutting the cats off (since i live in cali emissions are strict) also i wanted to put 3.73 gears on the car and if anyone knew how expensive labor is and what kind of acelleration gains i would expect, if anyone has any suggestions please mention

ckthecerealkiller

The only thing you can do is have the exhaust come right off the cats. For the gears, if you don't do highway driving, get 4.10's. MAJOR acceleration boost.

Caddstang

gears will help you're launch, and will let you get into the power band a bit quicker. As for the exhaust question, i'd leave the 4 cats on but have two high flow leaving the other two stock. You don't want to loose to much back pressure because that can cause a loss in torque down low.