Im not out to build the perfect NA im looking for daily driver exhaust, if low end and mid is increased thats cool for me seeing LA traffic is only going to let me do that

 

Ice, does your statement that true duals work best on NA's apply for aggressive streetported engines or bridgeported engines or does it only apply for stock NA engines?

 

My statements have only been proven on near stock ported (minor to mid-level street port) or stock ported engines.

I have not experimented with Bridgeported motors at all, so I can't say. Based on the thread that Nihilanthic posted, it would appear on paper (or electrons) that a true dual may not be as effective as tuned collector header could be on such a motor.

I suspect, that because typically a bridgeport or agressive street port/J port has a much peakier power curve, that since a header is tuned for a specific RPM, you could match up a little better. You know, if you are making power from 4500 to 7500 on a agressive port motor, you could tune the header for 6000 or 6500 and it would be a great match.

You might want to talk to the guys at RB or Mazdatrix for a more agressive porting situation and see what they recomend.

But if your power curve is near stock, you couldn't tune a header to work well the in the whole power curve from 2000 to 6500. Maybe if you did a varible dynamic exhaust (VDE??? instead of VDI) Or again, didn't mind the trade off/ compromise in trying for peak power.