You are being plenty generous with you horsepower figures there.Underdrive pulley 3-5 hp
Overbored Throttle Body 5 hp
Lightweight Flywheel No hp but moves you more quickly into sweet spot of rpm range
Cold air intake 3-5 hp
Headers 7-10 hp
Muffler 1-2 hp
Cams 15-20 hp
Intake Manifold 7-9 hp
Nitrous 25-75 hp on stock motor is safe
If you want just one mod for under $500 then I would put a 50-60 shot NOS system on it. Biggest bang for the buck of any mods. Easy to install, mileage is the same when putting around and only drops when you are pumping the NOS into the fuel system.
I was wondering what the best ways to increase hp are without spending thousands. Is there a list any where with cost benefit analysis for engine upgrades for the mx6 ls?
I'm not sure, but I got my probe GT rims (With Chrome) for $600.00 (Full Set)About how much can you get those RX7 rims for?
5w30 Mobil 1. Only and ever. Keeps the car quiet and its the best oil u can put in it! Its about 48$ for 4.4L but i'll never go back to anything. Its the best synthetic out there for our rides.You can lesson any worries about this by using 10/50w synthetic blend and keeping your valves clean. Cleaning your EGR Valve out with keep more gunk out and keep the annoying check engine light away.