Let's face it. V8's suck. Compared to a sweet, smooth-revving four, a big V8 has got to be the most monotonous kind of engine you can think of. "Blub blub blub". And compared to the incredible smoothness of a rotary, the V8 feels like it's clenching its butt-cheeks to force out even a few thousand RPM; screaming and squeezing itself to eke out even a few more revs, due to the sheer weight of all that reciprocating stuff. And that's with all the extra mass that such a behemoth has to lug around; hell, the weight of the engine is only just overcome by the extra power you can get out of the extra capacity!
And it's pretty obvious that all V8 cars are lead-tipped arrows. By necessity they have to be, because the donk weighs so much that the handling is pretty pathetic. And the solution oft arrived at to try and compensate are really heavy duty springs and shocks; and we all know how super-stiff suspensions make a car skip around, actually reducing handling potential. Not to mention the extra strain on the brakes, compared to a car with a lighter engine. Of course you might be thinking that newer aluminium designs like the GM Gen-III V8 are lighter than other smaller iron-block engines; but then if you went to the trouble of designing an aluminium block in those smaller engines, they'd obviously be lighter again.
And old! V8 engines are so old, with their overhead valves and pushrod actuation, they've just got no chance of getting the same efficiency as a smaller engine. No, when you weigh all the good against the bad, V8's are pointless.
Now isn't that a load of crap?
Essentially, I don't understand it; who cares how much power for the size a rotary has, how well a specific V8 pulls, how revvy a particular small four might be in a particular car. I just don't understand these "rivalries" between people that have an over-developed interest in one particular configuration or type of engine. I mean, really guys, get over it; no one particular design does everything brilliantly, there are compromises in everything, and these compromised engines are slotted into cars to fulfil certain roles as best they can. For example, a rotary is compact and quite powerful; add a turbo, and it pulls almost like a V8. But even with the latest electronic trickery, it seems they still use quite a lot of fuel to produce that power (although Mazda do seem to be claiming that they've overcome this problem with the 13B variants they've got in R and D). And adding to that, they're expensive; if everyone made them they might not be as expensive, but because only one manufacturer is involved, they have a small market (coupled with being able to charge what they want, because there are no competitors).
And everyone knows what the drawbacks of the big V8 are. Tongue-in-cheek I mentioned them above, and although over-exaggerated it is pretty-much true in a lot of cases.
A four cylinder is going to be down on power; they can't get too large due to balance problems (the biggest modern one that I can think of was the Porsche 968 engine at 3 litres). And when they get large, they're obviously going to get heavy too, and start suffering the problems involved in heavy engine componentry. Sure, you can bolt a turbo to a four and get power; but you can bolt a bigger turbo (or two) to an engine that's bigger in the first place, and get even more grunt. "What about sixes?" I hear you cry. Well, they're obviously a compromise between a smaller four and a bigger eight (or twelve), aren't they?
Really, half the negatives that people attribute to an engine design aren't necessarily due to the configuration anyway. I remember when Holden advertised the Commodore with a "Big Vee-Six", as though the "Vee" bit was what made V8's go; which is total crud. Big engines have big torque because they're big, full-stop. The only reason flat-eights and straight-eights and 5.7 litre fours aren't common are the logistics of balancing it and fitting it into a practical car.
Similarly, having a V8 engine doesn't stop a car from revving nicely and smoothly, and just because it's a V8 doesn't mean it has to be heavy. The Honda S2000 was originally conceived to have a naturally-aspirated V8 of around the 2 litres capacity; if they'd done that, it would've weighed a similar amount to the current four, would've made as much power, and would probably have revved harder and higher.
Basically, I really do believe that it's the actual car that's important, and who cares what engine is pushing or pulling it around. You can make a small six-pot which gives you a car more like a four (eg Mazda Astina V6, Lexus IS200). You can make a tiny, cammy V8 which revs its ring off. You could probably stick a 4 litre rotary in a car, had you the inclination; it probably wouldn't be all that difficult to bolt three Mazda 13B's (or two 20B's) to each other (imagine the length of the nose on that!); the result would pull "like a V8".
Also, a lot of people think of old pushrod 60's design V8's when they think of V8's, but don't forget that the Germans and Japanese are making some much more modern (and smaller) designs these days, that aren't necessarily dinosaurs. Also, the aforementioned GM Gen-III is actually a relatively advanced engine, despite the pushrods.
As far as I can see, it doesn't matter what the engine design is, as long as it suits the vehicle it's going into.
I mean, can you imagine how much of a disaster a Falcon or Commodore would be with a turbocharged 2.0 in it, a la Impreza WRX? Without that low-down torque, it'd be an annoying dog. And also consider Mr Average piling the 2.3 kids and luggage in the back during the school hols; with all that extra weight the poor thing would be on boost all the time, and highway fuel economy would be atrocious. Similarly, imagine how nose-heavy an Impreza with a 5.7 litre V8 would be; the engine would be over twice as long as the short boxer four, putting most of it in front of the front struts and making an already understeer-biased (but still fun and chuckable) car into a real anvil-nosed arrow. (Bit like a 5 cylinder Audi, eh?! - Ed)
Think how mismatched these two nicely-performing cars would be if you swapped their engines: the latest Mazda RX7 and the latest BMW M5. Yerk!
Nope, when next I hear the "Rotaries are best!" and "V8's rool!" arguments, I'll continue to drop in arguments on both sides, just to watch the sparks fly.
But meanwhile, I'll be thinking that in essence I don't really care ...
