Clive George wrote:
"The Natural Philosopher" wrote in message
...
Andy Champ wrote:
The Natural Philosopher wrote:

its rare to see more than 70bhp/liter from any normally aspirated
road engine.



Almost any bike.

Or if you want cars - Toyota 3SGE (in the MR2 Mk2 among others), 2
litres, 158BHP from the later UK models, and over 200 if you can get
hold of one of the Japan-only BEAMS engines. Though the last does
have variable valves etc...

Or the BMW 320, 150BHP/ 2 litres from 1991.

Or IIRC the Cavalier GSI, 156 BHP, 2 litres, and that's back a few
years.

Thse are pushing 75bhp/liter and are RARE. I did have an astra SRI
wahich was quite a lively injected 1.8 liter engine...otherwise it was
deeply dull.

So, the BMW engine is rare? Do you drive around with your eyes shut?

Another example from a few years ago - PSA 1.9 16v engine, 1905cc, 160
bhp. So 84 bhp/litre, over 10 years ago. No variable valves, and it was
a reliable engine.

None exceeds 100bhp/l;iter.

True. Those examples are all from 10 years ago.

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.

Renault clio - 200 hp from 2 litres NA.


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


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?



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

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...;-)


I wonder what it really produces after its been around a few years.




clive