No mods needed for the LRPs they are a direct bolt in. I do not know enough about all three engines to comment on what is better, but I do know if you plan to race in any ROAR legal races you may want to get the .28 as anything higher than that is not legal. Just check on the rules where you plan on racing.
Besides the motor you need to get a pipe. This is were things can get really expensive or sort of expensive. ERCM pipes are top notch, and also run top dollar. And if you feel like shelling out that amount of cash you should get the engine modded by ercm as well.
http://www.extremercmods.com/ that is their site.
I would recommend the above if you plan on racing hard, or just want something that is balls to the wall. Though all this sounds nice and dandy the fact still is you are new to the hobby and will make mistakes like we all have, do you want to spend your money now and possibly have something happen to it due to user error? Personally I would go for the .32 or the .28. (I have an XL with the .30) And I wouldnt mod it just yet. If you want when you buy the engine buy yourself a rod/piston/cylinder set so once you've ran the crap out of that motor stock you can get it modded. Or in my opinion just wait and see whats out when that engine is on its last leg.
Basically in all what I am trying to say is that until you know your specific truck, baby it a little even if you have all the cash to fix it.
for other hop ups theres RPM, Fast Lane Machines, new era models and some others if you want more let me know and I'll pull out my bookmarks.
Welcome to RCNT and enjoy the hobby
