[RICE RACING]

This is the basics Best to Worst

Spool response:
Stock Port
Bridge Port
Street Port

Sensitivity/tolerance to any type of normal exhaust:
Stock Port
Street Port
Bridge Port

Power band to suit stock gearbox:
Stock Port
Bridge Port
Street Port

Overall if you want response & most average power, tolerance to a normal exhaust system, best power band, nothing will beat the standard ports as Mazda made them. It's been proven many times over you can make well over 600bhp (engine power *insert what ever rwhp measure you wish for your country dyno type etc etc) on them with the turbo you are running. Bridge ports shit themselves any time you run them at tolerable noise level, street ports narrow up the power band and give you a another 500rpm peak power range but you loose a hell of allot in mid range power and spool. < If you combine the street port with a large turbo you will always loose response and mid range power.

Bridges are the worst idea ever for a road car, they are bad for many track cars too unless you can run it loud enough, and with a large enough turbo, otherwise they will make no more power than other types, but be double as loud, use twice as much fuel and generally be an outright pain in the arse. When you run it with the correct size turbo (or even the one you have) they have a really bad power band as the tq curve is flat so it will lack mid range power and only make maximum power at near it power peak, this give you less average power as you are pulling through that gear.

Best thing about turbo cars is to use the turbo and match the gearing so you have the maximum amount of power possible from your shift point to the beginning of the next gear and the only port that delivers that best is the stock standard one Mazda makes. If the power is not enough for you all you do is increase the boost pressure so far as the nature of the power nothing will be better than stock ports especially in the real world.