Q: I want to inquire about the turbo upgrades, what differs from stage 3 to stage 5. Approximate power gains and install requirements.
A: the big difference in the LVL3 vs LVL 5 is going to be minor changes in the upgraded wheels as well as materials. The LVL3 and LVL5 are both capable of pushing the 3.5L HP to near its stock limitations. On a stock engine, LVL 3 may very well be all you will ever need or use, if you plan on upgrading parts then the LVL 5 may be or benefit to you.