I have a 1990 Jeep Cherokee 2 dr. with the 4.0l..the year before they switched their stuff mechanically.

So i propose the question..

Should I presume doing performance upgrades to it, or should i just drive the jeep (as it is my 2nd/winter vehicle)..because I have noticed their are not as many upgradable parts for this engine as there is for the newer 4.0l.

 

Keep going.

 

The biggest and best performance upgrade you can do to the renix era motors is a fuel injector swap. Going to bigger injectors is about it as far as performance mods.

A warm air intake will cause you to burn more fuel, the headers well.. only flow marginall better then stock.

 

For your "second" winter vehicle....just invest in some good, cheap tires from treadwright.com/ I have two sets of tires from them and they work great and look good.

Maybe a mild lift...3 1/2 inches or less, and

change all fluids.

Done.

 

That is all garbage! You can so race a renix if you want! Rocker cam, bore it out! Turbo! Just cuz its a renix does not mean its handicapped.

 

keep going

 

I suppose you can but how are you going to capitize on the gains when you really cant do anything to change the timing curve or increase the fuel air ratio. I want to know more.


I also think he was talking bolt on mods.

 

stroke it... drop a newer head on it... heck drop a newer 4.0 in it... its not that hard... i did mine without even swapping a harness... 4.0's are a dim a dozen... all over craigslist... anywhere from $250 to $450 for the newers... complete motors... easyas pie! or you can buy a newer 4.0... stroke and build the crap out of it till the renix dies... then you got one to swap in thats bad ***... was kinda thinkin bout doing this myself Vs. building the motor in my jeep and it being down for a very long time...

 

ive also seen people make a "throttle spacer" That converts the intakes 3 hole bolt pattern to the newer TB 4 bolt pattern... anythings possible!