dentman

hi, i'm new here and i'm sure have answered this question a thousand times but let ask one more time. i have a 97 gt conv. auto i use the car only on nice weekends. i want to put 4:10's in the rear, do i have to do anything to the computer to make this change work? thanks for your help.

mdvaldosta

no nothing in the ecu on pre 99 cars, just a speedo gear change

dentman

thanks for the help. i'm having a tough time, i have been a chevy man forever this is my first ford. i love the carjust needs a little more power.i read in a mag about some new head mod for the older 4.6,s that will make the heads perform at least as good as the new style and in some cases even beter. this will be my first motor mod.

mdvaldosta

Yea its a PI swap. 99+ GT's used a better set of heads, intake, and cams to get the hp up by a ton - 45 rated hp to be exact. You can swap intakes and pick up a good 20 hp, cams for a good 15 hp, and heads for about 10 hp in themeselves (although Im sure you'd get the cams with them so it'd be worth 35hp + about 5-10 more because of the increased compression because those cars have different pistons than the 99+).

So yea, with a PI swap you can pick up a good 50+ hp and actually be faster than a 99+ GT because you'll be running higher compression. Gears would be probably the single biggest difference maker you can do on a car, 4.10's - 4.30's would be ideal for you if its your daily driver.

By the way, welcome to the forums and glad to see you're (hopefully) gonna be a Ford guy now