When a company thinks highly enough of itself to dub its cars “Radical,” it had better deliver on what its name alludes to. Well, Radical Sports Cars has been at it since 1997 and its sole mission is to build affordable cars that you can take out to the track and crush the opposition. That sounds pretty “Radical” to us.
The Radical PR6 is what its builder defines as a “versatile racer that’s at home on both track and hill.” This model sits directly above the entry-level Radical car, the newly released SR-1, which is pretty bad-ass in its own right.
The PR6 is a true “racer’s car,” focusing more on technical aspects, like lightweight body panels, precision suspension, and well-tunes gearbox, as opposed to brute strength, like other race car manufacturers. This is the type of car that can go out and wallop a 500-horsepower Corvette on the track, leaving the `Vette driver speechless when he learns how little power this compact racer is putting out.
So how much power does it really have and what makes it so darned special?
You’ll have to click past the jump to read our complete review and find out.
As much as we hate the saying, the outside of the PR6 “is what it is,” as it is truly a no-frills racecar. It adds in an authentic look and feel by gaining its inspiration from Le Mans prototype cars, bearing an extremely low nose, and tall front and rear fenders with cooling louvers in each fender. Unlike the prototype cars, this compact racer is an open air-style, so there is no cockpit or even a windshield to protect its driver.
The front end of the car features a honeycomb aluminum construction style, which meets all of FIA’s frontal crash test ratings. This system is designed to crumple, so it absorbs the majority of the energy from a frontal impact. Yeah, the car’s front end will be wrecked, but you get to walk away with just a headache and maybe a mild concussion.
The body is built from four-pieces of lightweight fiberglass. Covering the fiberglass is a tinted gel coat. There is no mention of color options, but we assume that you can opt for various colors.
Keeping the car glued to the road are a set of diffusers and a wing. On the front and rear, there’s high down-force composite diffusers. On the rear of the car, there’s a massive high down-force wing with side plates for added lateral stability at high speeds.
Behind the driver, in the required safety cell, is a 36-liter (9.51-gallon) aluminum fuel tank, insulated with foam.
The wheels measure in at 7 x 13 inches on the front and 9 x 13 inches on the rear. Keeping the wheels on the hubs are four lug nuts and the wheels are made from cast aluminum, which is just about as strong and lightweight as you can get without moving to extremely pricey composite wheels. Wrapped around these wheels are Dunlop Bespoke slick tires. You also get brake cooling ducts that connect to carbon composite cooling shrouds, to help keep the brakes at optimal temperature.
In all, the body measures 3.79 meters (149 inches) long, 1.03 meters (40.55 inches) high, and 1.55 meters (61.02 inches) wide. The Radical’s most notable feature and its biggest advantage over the competition is the fact that it weighs only 480 kg (1,058 lbs), which is only slightly larger than a large cruiser motorcycle.
Overall, the PR6 is built to race and that’s that. No more, no less… And we love it that way.
The inside of the PR6 is a lot of the same, as it is purely a race car. It actually somewhat resembles the KTM X-Bow, but with one fewer seat. The driver is in a central seating position wrapped in a safety cell that is integrated with the powder-coated carbon-steel frame. The safety cell meets MSA safety regulations.
The pedal box is fully adjustable, so those with larger than average feet or legs can operate the pedals with ease. As expected, the seat is purely for racing, leaving comfort out of the equation, and its harness meets all major racing association requirements, including FIA.
The steering wheel is a racing-style wheel (of course) and boasts a quick-release feature, so the driver can get in and out of the car in high-pressure situations with ease. There are two paddles on the backside of the steering wheel, which look like paddle-shifters. When you pull those paddles simultaneously, the wheel pops off, so don’t go trying to speed shift, via those paddles, or you’re in for a little trouble.
The gauge cluster is the main feature on the interior of this racecar’s interior. This display unit has an analogue LED tachometer, gear indicator, shift light, and four displays for various engine data. What’s key is the fact that this system is analogue, as opposed to digital. Though digital is great in fancy street cars, in a racecar, you need the precision of a set of analogue gauges.
The interior is exactly what we would expect of a true racer. Radical focused on the components that a racer needs every day and left all of the unnecessary garbage out. Good job!
Engine and Drivetrain
The engine is surprisingly underpowered for a sports car, but for one that weighs as much as a motorcycle, it’s just right. The engine is a Powertec 1,340 cc 4-cylinder variety, boasting a double-overhead-camshaft configuration. This engine pumps out a base horsepower number of 210 ponies at an astronomical 10,500 rpm and 130 pound-feet of torque at the same peak rpm. This engine can be tuned to pump up to 280 horsepower, depending on how deep your pockets are and how brave you are.
The engine features a four butterfly (four throttle body) fuel injection system. Each butterfly measures 41 mm to provide the cylinders with plenty of fuel. The engine also has a lightweight cold air intake box.
Keeping the engine cool is an electric water pump. A huge horsepower draw on any engine is the water pump and using an electric pump, while ultimately resulting in more repair headaches, eliminates this extra draw on the engine, squeezing a few more ponies from the svelte 1.3-liter 4-banger.
Surprisingly, this car is chain-driven. In the place of the driveshaft is a chain, which is likely as thick as 10 motorcycle chains to minimize power loss due to elasticity. The transmission is a 6-speed sequential gearbox and connects to the engine via a lightweight steel flywheel. We would have preferred to see an aluminum or composite flywheel for better response, but the heavier steel flywheel performs better on hill tracks.
The chain-drive connects to a torque-biasing limited-slip differential, which transfers power from a slipping wheel to the wheel with the most traction.
This combination of engine and drivetrain gets the PR6 from 0 to 60 mph in only 3.6 seconds and from 50 to 100 mph in just 6.1 seconds. It also allows the PR6 to hit a top speed of 140 mph.
Though the chain drive is a little shocking, we are overall pretty impressed with what Radical did with this compact 4-pot engine.
Braking and Suspension
The braking and suspension system is where the Radical PR6 takes home 1st place. The suspension is a fully adjustable Nik system on the front and rear with single adjustable coil-over shocks, which allows its driver to hone in the suspensions spring rate, rebound, and firmness for each individual track. It also boast unequal length – top and bottom – double wishbones with forged steel center lock hubs and interchangeable anti-roll links, for custom tuning to a particular track style.
On each corner of the PR6 is a 240 mm (9.45-inch) diameter ventilated brake disc. Also on the front and rear of this high-strung racer is a 4-piston caliper, custom built by Radical. To help hone in the brakes for each track on the fly, there is a dash-mounted brake bias adjuster to vary the front-to-rear brake power.
The Radical PR6 starts off at €43,390 ($54,185), and has options that can pump it to well over €70,000 ($87,415). On the base level, however, the PR6 is very affordable for the intermediate racer and has plenty of pop to win races in lower-level classes.
We could try to say that the KTM X-Bow is this car’s competitor, but that would be unfair, as the X-Bow is both significantly more powerful and higher priced than the PR6. In reality, the PR6, as an economy racecar, is in a class of its own, unless you want to build you r own for cheaper.
Well, we are slightly disappointed with a few things – chain drive, small rotors, and 13-inch wheels – but overall, we think that the PR6 is a slam dunk for any intermediate racecar driver. It is definitely not for a beginner, that’s what the Radical SR-1 is for, and it is not fast enough to hang with the big boys, which Radical has a solution for in the SR8 RX.
We give the PR6 a huge thumbs up, with some mild aftermarket modifications. Even without mods, it is still a good buy.
Lightweight racer for the true driver
Loads of optional add-ons for better handling and more power
Low base price for what you are getting
9-inch rotors and 13-inch wheels work on a Hyundai, not a racecar
Price soars when adding in extra goodies
Who does chain-driven cars anymore?