you'll love the upgraded cam.

drives like a whole new truck.

hell, you may even decide to forgo the LS conversion.

 

What's the most noticeable difference? Also what's the trade off?

 

I noticed a slight difference in the 4.0, still not enough to not consider a different power plant with more power. Trade off is going to be fuel efficiency but let's be serious here lol. A bit of pain to install but it's doable with the motor in the vehicle, I did it in both discos when I did HGs winter of 2020/2021, Crower cams in both. Don't remember which ones I went with off the top of my head.

 

better throttle response. slightly more power overall. fuel mileage stayed about the same for me. for comparison, i have a steel, winch front bumper, two (2) inch lift and 31" tires. i regularly get 12-12.5 mpg around town running 93 octane fuel. my other '04, which is stock, except for slightly larger than stock tires, gets about the same mileage.

and i get to keep the original engine where all the electronics are factory and therefore any future issues are easier to diagnose vs the LS with the cobbled together (albeit seemingly well done), hybrid Rover/GM system.