Throttle Body
 

Hello guys, New member here. I have just bought a 1999 Gt 4.6. The first thing I like to do is change the throttle body. Since it already has a 66.8 mm on it, will a 70mm be much of a performance boost or should I go for a 75mm?

A t/b on a near stock car will get you pretty much nothing....
Many better bang for your buck mods are out there...

Also, I'm pretty sure the 75mm unit will not fit normally onto the stock intake and changes to the intake housing may need to be made.... Also, Ford Motorsport recommends the addition of the 75mm unit only on race only cars....

If you have your heart set on a new t/b, the FMS or Edelbrock 70mm should go on with no problems...

After some research, I may have been wrong about the 75mm t\b (about intake issues), but you are still not going to see much (if anything) on a near stock setup...

Yeah man, throttle body won't add much. But it does all add up. When I put the FRPP 70mm throttle body on my 96 GT, ( i think the pre 99 modulars had only a 65mm t-body by the way), i didnt feel much other than improved throttle response. It' can't hurt the car, so get a throttle body if you want. Good luck with the car.

The best improvement you can make is a set of gears for the rear. RAY