This Mazda has three times the engine as stock and you can tell from the scream

We love dyno tuning, listening to those engines roar while fighting against resistance in a controlled setting. It's even more interesting when a car like this is strapped in.

This Mazda, a 6-rotor RX4 from Pulse Performance Race Engineering, roars like a lion during this dyno test.

The YouTube description says:

Initial dyno tuning of the PPRE fully tubbed, street legal 6B RX4. Remember this engine is NATURALLY ASPIRATED and on PUMP GAS

It's the pump gas that caught my eye, especially since this unit is making 813 horsepower. That is what is great about rotary engines: You can combine as many as you can get your hands on into one engine.

Listen to that scream as it strains against the dyno.