Daily Slideshow: This IS 350 Underwent a Tremendous Weight Loss

Bones Brigade

What you're looking at here is proof of a movement. Cars that play in the sand have long been heavy on tubes and light on bodywork, but beginning with cars like the Ariel Atom, heavily-tubed specials have been steadily gaining in popularity. And now the tube people are coming for your Lexuses. Connor Keough's 2006 IS 350 started as a daily driver, and then he drove it to Alabama's Krowrx company to have it converted to an exoskeleton track-day toy. The central idea behind exo build cars is to remove as much weight as possible, adding steel tubing along the way to keep what's left of the car together, add rigidity, and ensure safety. Recently Super Street sat down with JD Durham, co-founder of Krowrx and asked a few questions about the orange-tubed Lexus and an exo future.

>>Join the conversation about this stripped-down IS 350 right here in ClubLexus forum!

Spine and Spindle

Durham's first exoskeleton projects were, like the Lexus, rear wheel drive—a 2005 Mazda RX-8 with a 383 stroker V-8 and a 1995 BMW 540i. Next, he built an Acura Integra that Matt Farah panned, and riled the online Honda tuner community. The Lexus you see here is, of course, rear wheel drive, and features an eight-speed automatic coupled to a 300+ horsepower V6. Owner Keough said about the impetus for the build, "I'm already familiar with my car and there isn't really more you can do to these without spending a ton of money for power." Enter Durham and Krowrx. Durham on the car's construction: "The IS 350 was a build that shows more of a structure 'cage design. The design and look were a mixture between myself and the client, Connor Keough." He adds, "The Lexus is one of the fastest builds that I've done so far. I wouldn't underestimate the exo being an eight-speed auto. It would kick the rear end out on the interstate at 70 mph with no hesitation."

>>Join the conversation about this stripped-down IS 350 right here in ClubLexus forum!

Weight and Wind

So how much weight exactly does a bodywork delete save, especially after you add all those steel tubes? A lot according to Durham: "After the completion of Connor's build, we loaded it and took it up to Chicago. On the way, we stopped off at a truck stop and measured the final weight to be 2,283 pounds. We removed a little over 1,000 pounds! In my opinion, we unlocked the potential the engine needed to show its true power."

So what about the aerodynamic trade-offs? Durham mentions that his customers can opt for the addition of aerodynamic panels: "Depending on the customer's request, we can build a full track car that would perform better than a traditional exo and still be lightweight and aerodynamic." Though he admits, "The open exo builds that we've done haven't had any aerodynamic paneling so as a result, they do tend to perform poorly at higher speeds." Durham says the IS 350 starts to experience noticeable effects of drag at around 132 mph. You can still have fun over 132, but car and driver are going to struggle a little more than they would in a streamlined car.

>>Join the conversation about this stripped-down IS 350 right here in ClubLexus forum!

Power and Safety

Of course, one way to fight the wind is with horsepower. When asked if there was such a thing as too much power in an exo, Durham replied: "You wouldn't need a high-horsepower build to have fun in an exo, but it would make the experience more thrilling! Building an exo with any amount of horsepower is taken into consideration when designing the 'cage. In fact, I have a potential 700hp A4 we are building for a client as we speak, and engineering it as if it had 1,000 hp."

Durham was also asked his thoughts on the safety of his builds. "Any person driving an exo car, or any car/motorcycle for that matter, has to have a sense of direction and be aware of their surroundings at all times. I do imply safety into these builds. I want my clients to enjoy their builds and not worry about safety issues. That is why every build is built to each individual."

>>Join the conversation about this stripped-down IS 350 right here in ClubLexus forum!

On the Track

Given that Farah tested Krowrx's Integra build, dubbed the 'Xtegra', at Road Atlanta, Super Street asked Durham about the track times of his builds so far. Durham said: "So far, all of our cars have been for leisure only. The Xtegra hasn't ever been tested on a track; it was really never built to collect data. I am up for the challenge, though, if there is a person or shop out there that would want to build similar cars and go head-to-head with an exo versus non-exo. It would be very interesting to test in different categories such as Time Attack, autocross, drag, and drift." We agree, any volunteers? For its part, the exo IS 350 retains its traction control, as well as a few other items that would be overly-involved or unfriendly to remove, like the factory security system and emission controls.

>>Join the conversation about this stripped-down IS 350 right here in ClubLexus forum!

A Skinless Future

What does it cost to get a Krowrx exo-job done on your car? Durham says builds currently run between $4,000 and $6,000, plus the cost of your donor vehicle. He said that since the Xtegra story went live he's been deluged with requests: "Inquiries have been nonstop! We have set up a feature on our website to allow our clientele to build their own custom exo that meets their budget. We also offer to our clients a basic render of a custom-built exo design that is their own personality and style." When asked about his dream build, Durham said, "I don't think there will be an ultimate Krowrx build. I love to build new and exciting things, but I will be moving onto a tube chassis design of my own soon. I have a design already built in CAD. Now it's just putting the 3-D render into action." With an original tube frame on the horizon, perhaps clients could request it be draped with a Lexus body, completing the circle. One can dream.

>>Join the conversation about this stripped-down IS 350 right here in ClubLexus forum!

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