NA 9 port 20B?
 

Is it possible? Or does it exist already? I love the reliability of the NA motor, and if you could apply all of the same mods to a 3 rotor version, it would provide ample power and torque in NA form.

You figure that a streetported NA with all the bolt ons (intake, exhaust, pulleys, and electric fan) and dropping the power steering and airpump (gotta have my a/c), should have around 200hp and 150ft-lbs of torque. So a 3 rotor version would have roughly 300hp and 225ft-lbs.

It's too difficult to make power with the 6-port configuration. Most of the NA 20B's use the original or 13BREW housings.
http://www.mazdatrix.com/faq/port6p.htm

BTW, I got an advance copy of Corky Bell's new Supercharger book. It is better than the turbo book IMO, but still has all of the "Corky-isms". I think it's in stock now, so you may want to check it out.
http://www.amazon.com/exec/obidos/AS...736567-9986426

we are thinking an na 20b would have 300hp+ and torque too.
it would also run forever, but you would have to rebuild it with rew rotor housings 89+ na rotors, and a bit of porting.

mike

While I realize you don't get much from porting the 6ports, I was just taking the "every little bit helps" approach to the 3 rotor na motor. So there are guys out there with 3 rotor na's, just using the 4 port housings? Very cool. What I'm interested in is a mild, streetable setup that makes decent power and torque with good reliability. Do you know how much power they're putting out, and more importantly, what is the torque like in the low and mid-range? What I'm getting at is that I thought the 4 port setup on an na motor would have worse low end torque than the 6 port na; is this true?

Hehehe, I don't think that you really want any more low-end torque from a 3-rotor unless you just want to spin the wheels forever. Check with these guys for dyno info:
http://www.teamspencer.com/

Here's an idea... yank the engine apart and put in '89-up N/A rotors, they're the same weight, right? :D