Replacements for displacement
Rank heresy, right? Yet we somehow keep getting more ponies out of smaller engines. My old ’84 Mercury wheezed out 120 hp from a 3.8-liter V6; my current ride has a mere 3.0 liters and 227 hp.
Time was, the benchmark was 1 hp per cubic inch, achieved in the 1950s (in SAE gross terms, anyway) with a small-block Chevy V8: 283 cubes, 283 ponies. Eventually this became routine: my second Mazda 626 produced 130 hp from a fairly-ordinary DOHC four of two liters, around 122 cubic inches.
Now the number to beat is 100 hp/liter. The Mazda, at 65, falls short, as does the Infiniti, at 75. Still, there are cars meeting this spec that can be bought by mere mortals: GM’s turbo Ecotec four, bolted into the Chevy Cobalt SS, produces 260 hp from two liters. That’s 130 hp/liter. Then again, Chevy was intent on building a boy-racer; you won’t see numbers like this on workaday econoboxes.
Or maybe you will. FEV is showing what it calls the Extremely Downsized Engine, a turbocharged, direct-injected inline three of a meager 0.7 liters, which churns out something like 94 hp, about 134 hp/liter.
Now 94 hp doesn’t sound like a whole lot; after all, Honda bolts a 1.5-liter four with 105 ponies into the Fit. FEV is saying, though, that the EDE will produce 12 percent better gas mileage than conventional 1.5-liter fours like the one Honda bolts into the Fit, and the little Honda is downright abstemious with fuel unless you drive it like you just stole it, a characterization obtained from a former neighbor who owned one.
There are motorcycle engines that beat 134 hp/liter, some of them by rather a lot. I suspect, though, they’re too pricey to drop into an economy car.
Jeffro »
14 May 2010 · 9:17 pm
I wonder how drivable a car with a motorcycle engine redlined at well above ten grand would be?
CGHill »
14 May 2010 · 9:31 pm
The rotary in the Mazda RX-8 is redlined at somewhere around 9000 rpm; you have to keep it on the boil pretty much all the time, since it’s way short of torque.
So I imagine it’s like that, only more so.
(I have yet to hit the rev limiter in my current ride; the redline is a not-particularly-lofty 6600 rpm.)