If you select the upgrades (ID injectors, clutched pulley and trans tuning, and I would do all 3) you're close to $5k. I don't see any other fuel upgrades in their stage 1 kit, other than the injectors. Not even a JMS booster..Haha, I’ve been researching for two weeks now. Just wanted to get some reviews from here before pulling the trigger tomorrow. And, I’m not paying 5k! Actually, it’s less than 4, but that includes installation and dyno time.