Saving the Sports Car

At least once a year, this community is set abuzz by rumors that a successor to the S2000 is under development. So far, Honda has instead given us the deeply weird Crosstour and slow but strangely entertaining CR-Z. This has given me time to think about what I believe is essential to build a genuine Honda sports car.

First and most importantly, any S2000 successor should be lightweight. Although by no means slim, the original did manage to undercut most of its rivals in that regard. Materials technology and safety regulations have made opposing progress in this regard, so a curb weight near the original seems reasonable, say 2800lb. Aluminum construction is gradually becoming less cost-prohibitive, and a variety of interesting manufacturing techniques are available, ranging from the Jaguar XJ’s rivet-bonded conventional frame to the bonded-only monocoque underpinning current Loti. I’d like to see an aluminum semi-monocoque attached to separate aluminum or steel subframes, to keep repair costs reasonable. Carefully placed steel structural elements would provide rollover and side-impact protection. Body panels should be primarily steel; it’s less limiting in terms of achievable shapes than aluminum, and far cheaper than composite. Eliminate the power top; the Miata’s manual version works just as well and weighs significantly less. As a corollary, any engineer who mentions a folding hardtop should be dragged outside and shot.

Because of weight goals, a hybrid system should be avoided. Although the additional low-end torque can actually improve acceleration, hauling around several hundred pounds of batteries (or inertial storage) is always going to impair braking and lateral grip.

More broadly, an S2000 successor should be simple. Don’t add any accessories that weren’t present on the old car. In fact, remove power mirrors, cruise control, the electronic throttle, and the silly net pockets. Avoid options – colors only, and there’s no need for painted calipers or wheels over 17 inches. Current regulations demand stability control be fitted to all new vehicles; unlike many other sports cars, I would hope that in the S2000 it could be switched off completely. Deployable hoods for pedestrian safety are acceptable and in fact encouraged; the minimal weight added by the actuating system is more than offset by the aerodynamic and visibility benefits of a lower hood.

This leads us to the trickiest question facing any S2000 replacement, the powertrain. If it is to stay true to the original, the motor must provide performance in a unique way, contain innovative technologies, and stand up to abuse better than any of its rivals.

For these reasons, I believe the next Honda sports car should be a diesel.

Please, bear with me. Increasingly stringent emissions and noise regulations mean high-revving, naturally aspirated motors are a poor choice, both for cost and performance. Turbocharged four-cylinder petrol engines are rapidly becoming the norm in everything from family sedans to sports coupes. They are, almost without exception, characterless, under-performing, and derivative – everything Honda should strive to avoid.

The challenges Honda would need to overcome would stem from the conventional diesel’s unsuitably low redline and high weight, both areas in which other manufacturers such as BMW and Ford have recently made progress.

A turbodiesel of 2.0 to 2.5 liters capacity currently produces between 150 and 200 hp, and 200 to 300 ft-lb of torque. I would challenge Honda to build a motor of no more than 2.5 liters, producing at least 250 hp and 320 ft-lb. To maintain its feasibility for autocross and other motorsports applications, I’d like to see a redline of at least 6,000 rpm with a power peak no more than 750 rpm below that. The powerband of any such unit would be narrow with a somewhat unusual power curve – challenging to drive, compromising acceleration, and perfect in keeping with the spirit of the original.

Because of the tremendous stresses involved in compression ignition motors, they have traditionally been limited to the use of cast-iron engine blocks. These are significantly heavier than their aluminum counterparts. The necessity of turbocharging and urea-based emissions control systems also adds additional weight relative to a similarly sized petrol motor. Fortunately, recent advances in materials technology have yielded Compacted Graphite Iron, which is equally suitable for use in diesel motors, and can yield a weight savings of 10-30% relative to grey cast iron. To my mind, this seems to be a promising time for the advent of the diesel sports car. Lest my fellow enthusiasts think I’m trolling, let me make this clear – if Honda builds a car to the specifications laid out above, I will buy it.

Unless it looks like a Crosstour.

I’m sure many of you disagree with me, so please voice your opinions below. What do YOU want to see in an S2000 successor?

Image: Milos Milosevic via Flickr