Exhaust piping diameter question
 

I know that this has been asked many times, but I have searched until my eyes hurt and I am tired of reading all of those damn posts. I have an 88 NA. I want to put a whole new exhaust setup on it. Im not iterested in keeping it quite, but im not made of money so I want to try and keep the cost down. I was thinking a single outlet exhaust setup would be better performing and cheaper, but Im not sure if I should go single or true-dual. I am more interested in getting more low-end torque than high-end. Emmisions are not a factor. I was thinking a single outlet header, presilencer and single straight-through muffler. What piping diameter should I use. Is single outlet the way to go or is true dual better? I want to retain my 5/6 port operation also. So let me know what you guys think. Sorry this is so long. Thanks

Ture dual is best, but no ehxaust mod will give you low end torque on a N/A rotary. It's just the nature of the beast. I have NOTHING below 3500 RPM, but above that, she screams (when she is runnin that is). Go for a 2.5 inch diameter. It will flow better, freeing up some horses, but will still leave you with enough back presure. I am assuming you ar4e not keeping your auxillary ports working? If you want them to work (which is Mazda's way of giving us N/A guys bottom end) I reccomend a Bonez superflow system and a N1 catback. If you decide to go for top end (like the rest of us ;)) Then get a Racing Beat header, Racing Beat presilencer, and then an N1 single catback. Wait a minute...that is the very same syatem I am running!!;) It cost me about $900-$1000...

Racing Beat: www.racingbeat.com (also good place to get true dual set-up, but will cost you about $850)

Bonez Superflow system: http://www.rx7.com/cgi-local/2catalog.cgi?cat=4&part=1

N1 catback:http://www.rx7.com/cgi-local/2catalog.cgi?cat=4&part=3

So what are you saying I should do? True-dual or single?