Forced Induction 101… Supercharging
The next type of modification we’re going to address here is the use of forced induction to boost horsepower. While most owners are content with the rather spirited performance a stock S2000 offers with 240 HP, there are those for whom a 0-60 time of a little over 5 seconds just isn’t good enough. There are a 
number of ways to increase the output from the stock powerplant, (intake, exhaust, engine management, balancing/blueprinting, porting and polishing… etc.) pound for pound and dollar for dollar, forced induction is the most cost effective way to get huge horsepower gains from your S2k.
When we speak of forced induction, there are really two options: turbocharging and supercharging. Both are similar in that they force additional air and fuel into the intake to maximize engine output. The way they do this is what sets them apart. In the next few days, we’ll examine the advantages and disadvantages of both…
Today… supercharging:
A supercharger’s “blower” is driven by the turning of the motor itself. As RPMs increase, so does output. The result is a horsepower/torque curve that closely matches stock in shape, but with significantly higher peaks. A supercharger makes an S2000 more of what it already is, a very fast car at high RPM levels. While low end torque is improved, the nature of a supercharger won’t really allow it to give too substantial of a boost in the range below V-Tec.
There are two common supercharger setups available for the S2000. One is manufactured by Comptech, the other by Vortech. They are somewhat similar in price, features, and boost, but there are differences between them. The Vortech comes with an aftercooler, while this is optional on the Comptech. An after cooler is simply a radiator like device that cools the air coming from the blower before it enters the intake manifold. The advantage of this is that cooler air is denser than warmer air, and therefore contains more oxygen molecules per sq”. The concept of F/I is simple, the more oxygen you get into the cylinders, the more intense the combustion and therefore output.
An aftercooler really only provides a significant benefit at higher boost levels, and with the standard boost from both the Comptech and Vortech, (around 7psi) the aftercooler won’t provide too much additional HP. Once you start increasing the boost above 8-9psi, the advantages of an aftercooler become much more significant.
Because the default boost level of both systems is quite modest combined with the fact that the HP/torque curve closely matches the shape of a stock motor, supercharging is a fairly safe way to beef up your output without asking for major engine problems down the road. Also, because of the way these systems operate, they are smog legal in all 50 states. When installed by an authorized Honda dealer or their designate, a supercharger will also not interfere with the factory warranty.
Both the Comptech and Vortech offerings will give you an increase of about 100HP in their stock form, but with some tweaking can go way beyond that. At significant expense… long time S2ki member Sideways has managed to take the output of his sleeper Berlina all the way to 500HP and beyond! (He loves to troll the highways of Southern California looking for poor unsuspecting Ferraris and Porsches. The look on their faces when a Honda blows their doors in is priceless!)
On the other side of the forced induction coin is turbocharging… Stay tuned