I have hydroboost and whoa nelly, don't turn the car off until you are stopped... Vacuum is the cheapest upgrade, hydroboost is more complicated and expensive, and a reman powermaster is even more expensive. For the vacuum or hydroboost upgrades, do not get reman stuff, get 100% new. Cardone remans are junk, they are not rebuilt, they all leak, from my experience. I bought a hydroboost for a 84/85 Grand National and bought a '81 Caddy Eldorado master for it new Fenco. Problem solved. Can't go wrong with vacuum conversion either unless you drag race without a trans brake.