The 700 HP RennTech CLS63 AMG - /TUNED

MATT FARAH: We conclude our East Coast road trip here in West Palm Beach, Florida with this, the Mercedes CLS 63 upgraded to 700 horsepower. So imagine this scenario. You've grown up driving fast cars your whole life. You've had some Mustangs, some Corvettes, maybe even a Lamborghini or a Ferrari. But now you're older, you've got some grandkids, you're retired, you're down here in South Florida, and not Miami, mind you, West Palm Beach. Now I've got my condo over here and my yacht over there, and I need to get from one to the other in rapid, yet comfortable, fashion. I think I might have found the car for that. No one has ever accused famed Mercedes tuner RENNtech of building subtle machinery. In fact, their cars are nearly as outrageous as they come. From wide-body C-Class track cars to chrome-dipped SLs, if you can dream it, they can build it. Their shop, however, tells a different story. It's an unassuming facility on a side road in Florida with a gated lot and few windows. Stepping inside, though, will reveal all the equipment you would ever need to practically build a car from the ground up. From CAD stations and 3D printers to CNC machines, a fabrication center, a dyno, wheel, and body area, RENNtech, unlike their cars, is a total sleeper shop. And at the helm is ex-AMG technical director, Hartmut Feyhl. HELMUT FEYHL: So I got started with AMG when I was 17 years old. And that's a long time ago. The owner from AMG, Hans Werner Aufrecht, kept convincing me that I should stay, and they still needed me there. And I said, only under one condition, that I open my own company. So he agreed to that, and I opened RENNtech. The AMG model is just such a good base to work on, and there's a large percentage of the customers that buy an AMG that are willing to go the next step and the next step further to do modifications. There's still, here and there, some shortcomings, and there's just never enough horsepower, no matter what. MATT FARAH: When you're driving a tuned luxury car, it's not really the same as any other kind of car. If you're driving a really huge horsepower Camaro, or a Supra, or something like that, there's certain nuances that you come to expect. Maybe it idles higher than normal. Maybe the air conditioning doesn't work if you're driving fast and it's too hot out. Maybe the ride is a little rough. But when you're driving a modified AMG car, you really don't want to deal with that kind of stuff. You're a luxury buyer. You're spending $120,000 on a car, and you want more power, but really without any of the sacrifice whatsoever. So if you're going to build and modify an AMG car, you have to really keep those things in mind. And the good news is I've been driving this car around for a little while now, and I can't find any nuances about it that take away from the Mercedes feel. So let's go over what they've done to the car. Under the hood, you've got a 5 and 1/2 liter bi-turbo engine, hand built by AMG. They've added a 20% larger Garrett ball bearing turbo chargers, software, down pipes, and high flow cat. That's it. And for that, you get 700 crank horsepower, 600 wheel horsepower. And this is in a car that holds four people and is currently giving me a fully cooled butt massage. Automatic. It's in sixth gear right now, Sport Plus. 1,000 RPM, drop three gears. [INAUDIBLE] It's seriously, seriously fast. That's brilliant. The giggle dyno says that this is making 700 horsepower. The giggle don't lie. You can read dyno sheets all day long, but If I don't laugh, it ain't making the power. It's making the power. HELMUT FEYHL: With this one, we have, right now, over 700 horsepower, over 600 horsepower in the wheels. And we'll probably end up somewhere between 750 and 800 horsepower by the end of the year. Quarter mile we did at 10.70 at 132. That's on street-legal, [INAUDIBLE] radials. And that, of course, will improve, too. Our goal is, at least with this car, all set up and trimmed for quarter mile, to go under 10 seconds. So we want to go in the nines. MATT FARAH: This is RENNtech's prototype development car, so the kit isn't complete. And what I mean by that is, because they're working on it, because they're still testing it, and we're just getting a sneak preview of it, all the carbon fiber parts aren't actually carbon fiber right now. They're actually plastic wrapped in carbon look vinyl. But the final pieces will be dry carbon fiber. HELMUT FEYHL: In our facility, we do everything. We do from the designing, the idea, the design, the prototyping, the testing, dyno testing. We have CNC machines, fabricating, welding, two full-time-- three, actually-- three fabricators, machine for machine shop, prototype 3D printer. We have laser scanner to scan the cars to bring it into the computer, bring the bumper skin into the computer so we can design, in this case a splitter, on top of it. And then get all the CAD data together and print it in our prototype printer, check it for fitment and design corrections, and everything is done. Make the tool, and for that we send someplace else and then have the carbon fiber piece, whatever it is, produced. MATT FARAH: Things I don't like about the car. That radar detector, which I'm not even fully sure how to turn off, what it does, or how it works, it's not a V1, and it's hard wired to the car. That's kind of annoying. The front splitter. I understand why it's there. They tell me it's functional, at least in CAD. It's a little much for me. Front splitter I understand, but the little winglets on the side-- What are you doing? What? Lasers. Oh, it's lasers. I'm not getting lasered. Shut up. This is why, if you have a car, you get a V1. That's it. V1 is the only radar detector that works. This thing sucks. Sorry, Hartmut. I like your engine. This thing's a piece of crap. What this car loves to do, and I'll turn off traction just to show you, is it loves to break the tires loose while moving. So I'm just going to mat it right now. Watch what happens. So even at 40 miles an hour, if you mat it, the back end just decides it wants to dance all over the place. Let's do that again. [LAUGHS] $120,000 luxury car, seating for four, massage seats, and rolling burn outs. What is not to love about that? HELMUT FEYHL: And the priority is that it's an everyday car, that the driveability and the reliability does not suffer. All these years, for over 20 years now, that is always the main concern. I would call my customers conservative, even though you can't quite call this conservative. But they buy a Mercedes because of what it stands for and the AMG version because of what it stands for, the styling, the performance, the reliability, the technology, the high-tech stuff, the safety. All those things are very important. That's why you buy a Mercedes. And everything that we do does not compromise that, or we don't do it. MATT FARAH: I can take this to the club. I can go to church in this, if that was my thing, which it really isn't. I could pick up three girls, drive them around. I could take the kids to school, pick up my grandma at the nursing home. And then if I ever had a bad day just-- [ENGINE ROARS]. There are not a lot of cars out there that will fully break the tires loose from a 40 mile an hour roll. This one does. AMG, RENNtech muscle car with luxury. *** do I love this thing. I really would have liked to test this car on the Autobahn or on some windy California back roads. It would've been nice to drift it at the track, but JF doesn't give us enough money for that. In all honesty, the car deserves the chance to properly stretch its legs as one of the most ridiculously overpowered sedans money can buy. But this is what Florida driving is like, straight, flat, and crowded. You need good air conditioning and if you're old enough to voluntarily move here, massage seats. The best you could hope for is the occasional quiet beautiful spot in a nature preserve to appreciate the car's styling and its ability to do massive smoky burnouts.