If I am wanting to get the most power I can out of my 4.0 what mods are worth it? I mean without digging to deep into my bank account. No stroker or turbo set-ups.

 

injectors, bored throttle body, cold air intake, ignition upgrade and free flowing exhaust

 

plus 91 octane gas.

 

Where can i buy all these upgrades? everyone says go to the junk yard and find dodge neon injectors? lol

 

the for sale section on here some one sells them all cleaned up and ready to use

 

You need more air and fuel for more power. Bigger TB, bigger cam, better flow out of the heads, and better flowing exhaust.

My buddy just did a head port, higher ratio roller rockers, cam upgrade, and header on his Cherokee and the thing hauls. I think a TB upgrade would make it even better.

 

 

So one more question. How will this affect my mpg? Better or worse?

 

said more power, not less. the notion that octane increases power is a myth. The octane rating for gasoline has nothing to do with the amount of power locked inside of it – it actually relates to just how much a fuel can be compressed before igniting. The higher the number, the less likely it is to ignite under pressure. Higher Octane fuels are for higher compression engines. It does absolutely no good to run it in a jeep unless the compression ratio has been increased.