The Ultimate Street Mazda | Mazda 20B 3-rotor RX-3

Posted by: Jeremy Patterson on 11/17/2021

There’s no denying the pure raw badassness of a built rotary engine. Sure, you can drop a massive cam in a V8 and make it sound awesome, that’s one of my vary favorite things on earth in fact. And you can even build a six cylinder to sound purely wicked – think, Supras and turbo Buicks – but when it comes to an engine that just sounds like it’s completely pissed off and ready to rip your head off, it’s hard to beat a rotary.

This RX3 sedan – that’s right, I said sedan – is a perfect example of just how insane these little engines can be when pushed to the max. With a PROMAZ-built 20B 3-Rotor under the hood, this four door family hauler cranks out 560+ horsepower on just 14 pounds of boost. To make it even more impressive, this is on pump gas. With some race gas feeding the magic triangles and some more boost, it could easily top 700 horsepower I would think.

All of this is possible thanks to PROMAZ’s bridge port build, which allows the car to breathe much more freely. With the Garrett GTX42 turbo feeding the gorgeous polished intake. The fuel and ignition is all controlled by the Microtech LT16c ECU and one of the cooler components of the car is the awesome Samsonas sequential six-speed gearbox. All of that power is sent rearward through a 9 inch rear end to handle the abuse. The 19” Simmons wheels set off the looks of the car, which are understated if you don’t count the rolling stock.

We’d be curious to see what a car like this could run in the quarter, both on the 19” wheels with radials and with a smaller wheel with some drag radials or slicks mounted up. We’ve certainly seen some wicked rotary combinations running some great elapsed times in the quarter, and there’s no good reason why this one wouldn’t be able to rip off some great times as well.