i would do a 410 gear, tr 220or the tr224,springs and a tune of course.get some stock wheels for some slicks. my buddy bluecajun5.3 has a rcsb 03 with a tr 220,3000 stall,410 gear,tune ,and supporting bolt ons and his truck just ran 13.14@100 in like 90* weather. if your still not happy theres always laughing gas to cheer you up

seth

 

I would have to disagree with the gear swap, I just dont think it would be worth the money performance wise. Drop in a TR220 with a new set of springs and pushrods, get yourself a few bolt-ons such as underdrive pulley, e-fans and so forth. Use the money you save from the gear swap and invest it toward a custom tune from one of the sponsors to the right. The 4.8 is not a torque monster, so dont expect it to have a lot of torque. If thats what your looking for, then you should look into a 6.0L and T-56 swap and not waste your time or money on the 4.8.