The Caterham Seven is almost the default choice for drivers looking for trackday thrills or a back road blast on a Sunday morning. The appeal is in the Seven’s simplicity, lightweight and communicative chassis. That, and wonderfully rapid acceleration.
The Caterham Seven Roadsport is perhaps the entry-point into Caterham’s range of back-to-basic open-top machines for those looking to get their pure driving thrills predominantly on the road rather than on the track. Unlike the more hardcore Sevens such as the Superlight range, the Roadsport comes with a windscreen, some semblance of weather protection and even a heater as standard (such modern luxuries are cost options on the Superlights).
Caterham Seven Roadsports also run less sophisticated suspension, with a narrower front track and less adjustability (the platforms and dampers aren’t variable). Secondly, Roadsports get a five-speed gearbox in place of the six close ratios on Superlights.
Here we’re driving the Roadsport 175, which is the latest and most powerful variant of Caterham’s Roadsport range. Unlike the 125 and 150 versions, which use a 1.6-litre Ford Sigma engine, the 175 uses a 2.0-litre Duratec engine producing, you guessed it, 175bhp.
By way of performance comparison, Caterham claims 0-60mph times of 5.9sec, 5.0sec and 4.8sec for the 125, 150 and 175 versions respectively. All three roll up with the same claimed weight of 550kg, which gives the Roadsport 175 driven here a power-to-weight ratio of 318bhp per tonne.
Given that the engine powering both the Roadsport 175 and the Superlight R300 is exactly the same, the noticeable difference in character between the two is surprising. Mostly this comes down to the different gearing. With the Roadsport’s five speeds, you find yourself changing gear less and relying more on the torque, which is something the Duratec powerplant is not short of. Just 139lb ft may not sound much, but in something weighing 550kg it’s plenty to be getting along with.
The difference in outright pace between the Seven Roadsport and the Superlight may be slim – just 0.3sec to 60mph on paper (although as a percentage of not very much that’s quite large) – but in reality the Roadsport is a lot less manic. Whether that appeals will depend on how you intend to use your Caterham.
For the track-day regular, the six-speed gearbox of the R300 is probably the way to go, but if you’re going to be spending most time on B-roads, mixing it with other traffic, the more relaxed delivery of the Roadsport makes sense and, compared with the lesser Roadsport variants, the Roadsport 175’s additional mid-range punch makes easier work of overtaking.
The suspension, while lacking a little of the Superlight’s sophistication in the way it deals with bumps, still finds a nice balance between comfort and tautness. This particular car was not fitted with the optional limited-slip differential (also a cost option on the Superlight), which is a shame, because the Roadsport 175 is brisk enough to easily break traction.
The beauty of Caterham’s operation is that there are few hard points in the range, and almost endless personalisation. The trick is to choose the right starting point, depending on what you want from your Seven.
Caterham has further made this decision even harder with the introduction of the Supersport model. It shares the Ford Sigma engine and five-speed gearbox with the regular 7, but is stripped of any luxury concessions like the Superlight models. It is the ultimate back-to-basics Caterham, and the price reflects this; it can be brought as a kit for less than £20,000.
The Supersport is fitted with sprint gear ratios which offer ferocious acceleration; despite having just 140bhp, Caterham claims a 0-60mph time of 4.9sec. The lack of a windscreen emphasises the sensations of speed. The handling is predictably spectacular, with traction aided by a limited-slip differential and Avon CR500 tyres. For trackday and hillclimb regulars without the budget for a Superlight, the 7 Supersport is ideal.
For road use, there is probably better value in the less powerful (but still quick enough) Roadsport 125 and 150 versions. And while the 2.0-litre, 175bhp Duratec engine is a cracker, its extra performance makes it better suited to the more track-oriented Superlight chassis while offering power and pace that’s fully exploitable on the road without constantly propelling you to licence-losing speeds.
But if you want a road Caterham with a touch more long-distance comfort, but still with the ability to stay with a 911, the Roadsport 175 is an excellent place to start.