MazdaRx7Racer4Life

can it be done? Would there be a big increase from a 13b na to a 20b na, how many ports does it have, give me the specs someone.

inukai

Hi

RE-A is now producing 20B NA motor for a race car.
I will post pics later.

Dyre

You're going to spend just as more money that you would just running the stock twin, and make a whole lot let power.
Figure 10k plus to do it.

NZConvertible

Yes, there are a few running around over here. It's no harder than de-turboing any other engine.Around 50% more than a 4-port 13B. Figure ~200hp. Two side inlet ports and one peripheral exhaust port per rotor, just like all 4-port 13B's. Mazda never made NA 20B's, so there are no factory specs.

Like Dyre said, you're not going to save much money running without the turbos, you'll just have a lot less power and torque. Even on mild (read safe) boost, the twins will give you 300+hp and more torque than a 300hp 13BT.

vaughnc

How would you re-tune the 20B for more NA low end torque anyway? VDI, 6port (err 9 port ??), smaller exhaust ports, etc..

I'm assuming you'd want to swap out for higher compression rotors out of the NA engine.

$150FC

no it wouldn't be nine port, the ports is per rotor bah argh >