Hello all, I have a 2003 rcsb that I have lowered and installed Yukon buckets and console in. I have sound deadened it and installed an amazing sound system in it as well. This truck is very comfortable on the road. I'm about to turn over 200k on stock engine. I have a K&N cold air intake and Magnaflow cat back installed as well as a Backflip G2 bed cover. I work 120 miles form home, and even though I don't go home every day, I still spend a lot of time on the road. I average around 23-25 mpg on the highway. I'm thinking about the engine upgrade, and having read lots of posts regarding swaps, builds, power adders, but I'm not sure the best path for me. I'm looking for optimum performance in the 50-100 mph range. I'm fairly certain that I want a turbo kit, I just don't know whether to freshen/upgrade my stock engine and add turbo later, or start with something stronger to begin with ( lq9/ ls6 )...etc. Any insight would be appreciated. Fwiw.. I had a 2005 CTS-V with an LS-6 and I LOVED that motor. Thanks

 

If it was me, I'd just slap a turbo on the stock motor and call it good.

200k miles isnt even considered high miles yet, I bet the cross hatching is still there in the cylinders. It never hurts to re-seal the motor if it leaks some. But I'd toss in some new lifters/headgaskets/springs and do a turbo kit.