This Homemade 2000 HP Mazda RX-7 Is Determined To Shred Its Tires

Meet Top Gear Tuning correspondent Rob Dahm with his episode 1 of American Tuned.

He starts the series off by talking about some of America’s craziest tuners, introducing his own 4-rotor Mazda RX-7 which he built by hand.

That’s just the beginning, as we descend down the rabbit hole to see one of the craziest – and fastest – custom builds we’ve seen so far.

This RX-7 monster is a dream that refuses to die

Rob isn’t just obsessed with cars, his passion is taking a car and making it do things automakers never even dreamed of.

His first sports car was Montego Blue, but the story got interesting when he decided to build his obsession – the all-wheel-drive four-rotor Mazda RX-7.

In any case, for someone with no automotive background, there is the question of how this car came to be. It was a combination of two things.

On the one hand, the Internet helps with so many resources available, on the other hand, an absolute obsession to do everything that led him to achieve this dream goal.

Also, once the work has started, people usually come to help.

Related: It’s Not Legal, But This Rocket Bunny Mazda RX-7 Is Really Cool

With a little help from around the world, the beast was born

In a normal situation, there is a racing team or engineers working on a car and each of them is an expert in their trade. Rob had none of that.

It was his job to learn to tune, build and even solder. Also, Rob got a little help buying some parts from different cars that came out in the world. For example, it has a front differential that was a rear differential on a BMW E36, there are parts from Corvettes, parts from Nissans.

This type of car requires every kind of fabrication and machining imaginable. Rob’s partner helps him a lot with fabrication and machining, and problem solving.

In Rob’s opinion, the coolest thing was solving the all-wheel-drive system using a Nissan GT-R transfer box that transfers power to the front. Turning it off makes the Mazda 100% rear-wheel drive.

Because the rotary engine produces so much hot exhaust, there’s the 106mm Garrett turbocharger. There are carbon fiber axles. The rear of the car has a 50 gallon gas tank, which is understandable since it uses over a gallon and a half of fuel for a single pull.

The magic of this Mazda lies in its heart – the rotary 4-rotor billet engine, with inline four rotors. They stand straight like Lego giving the torque and power needed to keep the car rolling.

Its transmission and everything together provide about 2000 hp to all four wheels.

Related: 10 Reasons Gearboxes Prefer FD Mazda RX-7 Over RX-8

From the garage to the circuit, this car was born to smoke the tires

It all looks great in a garage and on paper, but you have to see it all working on the track, to go and shake the car. After all, the reason to build a car is to get around.

Rob jokes that his steering wheel is upside down because he’s not an alignment shop. It focuses on the entire steering, from the steering wheel to the steering rack. He’s very particular about it, so he has fluted, drilled, and even welded things. At no time after could the steering column fail it.

The first thing it does in testing is try to hold the pedal down in a certain place, and that matters a lot because when you step on a car’s pedal, the computer tries to predict it.

He tries to adapt to it and with tons of power he could do new things.

So what Rob is trying to do is hold the inputs on the pedal at 30% and then watch what the car does as it gains power and speed. This way it tries to tune the car, like how much fuel the engine needs.

With that much power, Rob has to be careful because he’s sure that at 50% power this car will kill him. Thus, tuning is a very big responsibility.

Afterwards, Rob drives off in the bespoke car of his creation. He tests all the different parts and assemblies he put together in this car, and it’s overwhelming.

Rob says that this time he’s looking for the limits of his car, and he finds them in the form of broken suspension and drivetrain components.

In a car as powerful as this, it’s like a stamp of approval. Now he can go back to the garage and work a little more on his little car and grow as it grows.

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