intake

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.

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