Honda Civic Si sedan
In our Volkswagen GTI dyno results piece, we wrote that an engine should be tuned by "some mad-scientist . . . whose neck hair stands at attention when he hears a fantastic, resonating intake honk; whose eyes roll back in his head when his engine has a surge of torque at 4000 rpm; and who laughs maniacally when the cacophony of valves, pistons, and explosions comes to a crescendo at some ludicrously high redline."
Well, guess what? That mad-scientist engineer dude exists. He works part-time at Honda, and he oversaw the development of the Civic Si's engine. We certainly have a few big gripes about the Civic, especially its electronic throttle mapping, but not a single beef with the Si's engine itself.
The Si's 2.0-liter, four-cylinder screamer is rated at 197 horsepower and 139 lb-ft of torque. That's right at the magical 100-hp-per-liter mark that only the best normally aspirated engines in the world can manage. The trick is, of course, that Honda doesn't start painting the tachometer red until 8000 rpm.
Horsepower is a function of engine speed--the faster an engine is spinning, the more power it will make for any given amount of torque. Honda's VTEC ensures that the torque curve doesn't drop off at high revs by switching to a much more aggressive cam profile at 5800 rpm. The result is peak torque right after the changeover, at 6200 rpm.
On the dyno, the Si put down 180 horsepower at 7800 rpm, right ahead of the VW GTI's 2.0-liter turbo four. The torque curve isn't so much of a curve, it's more of a flat line with a hiccup when VTEC switches cam profiles at 5800 rpm. As with many of their high-performance engines, it seems that Honda might have been able to make the VTEC cam profile switch at a slightly lower engine speed for a smoother transition. On the other hand, the sudden kick-in-the-pants increase in torque-and sound-is precisely the thing that would make the mad scientist happy. It sure made us smile.
The problem when you're playing with cheaters (i.e. turbos) is that you often lose by not cheating yourself. The Civic Si swings the same 200-horsepower bat that the GTI 2.0T does, but it isn't even in the same ballpark where torque is concerned. Mash the throttle in 4th gear at 60 mph in the Civic, and you'll summon 116 lb-ft of torque. Do the same in the GTI, and you get thrown back in your seat to the tune of 187 lb-ft--that's 60% more! That said, the Civic Si peaks at 134 lb-ft, and didn't stray much under 120 lb-ft from 2500 rpm (as low as we were able to obtain reliable data) all the way to redline. Peak torque of 134 lb-ft at the wheels from an engine rated 139 lb-ft is really, really impressive. And arguments about turbo lag here are moot; the Civic Si's drive-by-wire throttle is so slow to respond that you can literally press the throttle to the floor and release it without any response.
Regardless of its relative disadvantage to the cheaters, the Civic Si has s a truly entertaining engine that's filled with tech features that (other than the throttle calibration) do nothing to detract from the feeling that someone poured their whole soul into its development. It takes only one trip to the redline to envision that mad scientist thrashing this car mercilessly, laughing all the way. ...next page >>