Throttle Body Upgrades

So you want to squeeze as much horsepower and increase performance for your 4.0 in your XJ or MJ?   A bored throttle body is an easy upgrade to do just that.  

  • There are various sizes of bored throttle bodies ranging from 60mm all the way up to 68mm!  
  • HO 4.0Ls factory throttle bodys are 58mm.   Renix is 52mm.
  • The most commonly used size is the 62mm.   If your 4.0L is stroked, you may need something bigger than 62mm depending on your intake manifold bore.

Do It Yourself Links

Where to Buy Bored Throttle Bodies