"The Natural Philosopher" wrote in message
...

Let's look at some more recent stuff. Peugeot 206 - 180hp from 2 litres
NA.

I couldn't find a Peugot 206 with a 2 liter engine. Anyway thats still not
100bhp /liter.

206 GTI 180.


Renault clio - 200 hp from 2 litres NA.


197bhp on a 16v engine doing 7.25K RPM. So still not 100bhp/liter.

Granted. _Only_ 98.5

2001 - Honda civic type R. Rather popular hot hatch, probably because of
the 197hp from a 2 litre N/A engine. (the S2000 is 237hp from the same
size engine).

Honda sports cars have what amounts to racing engines in them. Again and
exception. 8300 RPM. who really is going to redline at that sort of RPM?

FSVO "racing engines". They're reliable, built to last, and are happy
pootling around - ie perfectly good road engines. And the answer to your
question is "the person who wants to go fast" - they're designed to run at
that speed.

Now obviously these are all at the quick end of the market. But they're
there, easy to get hold of, and reliable. Which sort of makes your
contention that 70 bhp/litre is rare a bit wrong.

These are all boy racer products competing on specmanship, and probably a
LOT less when they are actually put on a rolling road.

Oh dear. Those are real numbers, not the made up ones preferred by dodgy
"tuners". You're making the mistake of comparing your experience from quite
a while ago with what's happening now.

BIG fast cars knpow that reliability and smooth power deployment comes
with bigger engines run with less aggressive port timing.

The thing is, the engines we're talking about here _are_ reliable and don't
have the lumpy cams you're thinking about.
Oh yes - BIG fast cars like the BMW M5? 81 bhp/litre in the late 80s, 89
bhp/litre in the early 90s, and 100 bhp/litre at the moment. The smaller M3
only had 343hp out of a 3.2L engine 7 years ago...

If you blueprint and balance an engine of course with sufficiently large
porting and an RPM limit up around 8300, you can get 100bhp per liter,
till it wears out. with VVT it may even be suitable for road use...;-)

You're behind the times. Yes, VVT is a key part of these engines (though not
there on eg the PSA 1.9 16v 84bhp/litre engine). Materials, technology and
engineering have all moved on from the engines you're thinking of - more
valve area, properly analysed air flow, better tolerances in manufacturing,
etc all mean what you consider as racing car stuff are actually available in
road cars - and reliable too.

clive