HOME > Roadster > Mods
Roadster link to concept link to specs Mods links

"To mod or not to mod, that is the question."

Tricky one this. My Roadster feels slow after my 106 GTi, but maybe I'm missing the point. What the Roadster lacks in out-and-out performance, it makes up for in the novelty of having no roof. Well, for the moment at least.

The thing is, you never EVER get your money back when you modify a car. If people tell you it's possible, they're probably trying to sell you their (heavily modified) car after someone else has told them it's worth bugger all.

And yet... there's a strong draw to doing it for serious petrolheads. I'm not talking about modifying cars in the garish Max Power (Muppet) way, which is frankly all about show, not go most of the time. Perhaps "tuning" is a more appropriate term than modifying...

Turbo or Supercharger?

The Roadster engine is basically a turbo engine with the forced induction gear removed, so adding a turbo or supercharger is much less of an issue than it might be with a high-compression NA engine. The Elise for example needs new pistons when it is supercharged by Turbo Technics, because there wouldn't be sufficient volume in the cylinders to squeeze in the air that the supercharger can deliver.

Conventional wisdom dictates that superchargers give a more linear power delivery than turbos, due to the fact that they are mechanically driven and don't have to wait for the exhaust gases to develop enough speed to drive the compression side of the turbo. Hence superchargers give boost from c.1,500rpm, whereas a turbo needs 2,500 or 3,000rpm before it gives boost.

So what, you might ask. The fact is that the turbo can suddenly come on boost, which presents a challenge to the driven wheels to provide enough traction to get the torque to the road. The supercharger on the other hand is much more linear in its delivery, smoothly adding power at all engine speeds.