I have the 4.2L I-6. Wish I had a V-8. Thought about a transplant, but just too costly. The 5.3L in the Envoy Denali shorty is sooo sweet. I can really tell a difference, even though the Denali only had 50 miles on it when I drove it. Some owners don't care about power, but if you do, get a V-8.