Cars have come a long way since the 1970s. They’re safer and smarter. They’re more powerful on average, too, but more than anything, they’re more efficient. Part of that efficiency is down to better engine technology, but an even bigger part is thanks to more sophisticated transmissions play here as well. One of the most efficient and generally well-liked transmissions today is the 8HP eight-speed automatic from ZF, and it absolutely transforms this triple-rotor Mazda RX-3.
If you’re unfamiliar with Mazda’s rotary engines, the 20B is a three rotor engine that originally saw use in the Eunos Cosmo luxury coupe of the 1990s. It’s renowned for being incredibly smooth, powerful, and almost catastrophically thirsty for fuel. The RX-3, meanwhile, is one of Mazda’s earlier rotary-powered models, predating the better-known RX-7 by nearly 10 years and the Eunos Cosmo by two decades.
The Australian customer who owns the RX-3 in this video bought it as a fully built drag racer, so the changes they’ve made turn things down a little and make it into a street car by adding comfort and convenience. In its drag racing form, the car came with a two-speed automatic transmission, chosen for its ability to take tons of power from the turbocharged 20B, but what’s good for the strip is rarely good for the street.
While there are many really cool things about the ZF 8HP, the coolest is that it’s electronically controlled, so it becomes highly configurable with the right software. For example, the person who owns this Mazda has it set up with a trans brake in case he wants to drag race it. These transmissions have also proven extremely reliable, and some variants can hold up to 664 pound-feet of torque without modification, making them even more attractive for performance builds.
Now, if you’re the kind of person saying that you’d only ever have a manual and that autos are dumb, I get it. Older automatics are slow-shifting, heavy, power-robbing slush boxes, but things have moved on considerably since the era when four or five-speed autos were the norm. The 8HP, on the other hand, shifts super fast and holds gears when you want it to (subject to programming, of course), and I would rather have a car with this gearbox than a lot of the only “meh” manuals that are out there.
So, what other classic car might you want to see get an 8HP conversion? Let us know!
