In a message dated 6/13/0 5:15:58 PM, mikech@sprynet.com wrote:
<<All of the examples you cited require an extremely high compression ratio,
something our Spitfires do not have>>
Well thats almost right. Diesel is the only one that requires a high
compression. Methanol runs fine on low compression but with run even better
on high compression AND high boost. Nitromethane on the otherhand is a no no
with high compression, if you do, depending on what you are doing, run the
risk of hydraulicking a cylinder (nitro has an A/F ratio of around 1 to 1).
Having had a few hard core drag vehicles, including a blown alky funny car
for one, plus building engines and having a severe love affair for
"alternative" fuels, I lucked up and got a lot of experience with a lot of
this stuff. True you can run a high octane fuel in a low compression engine
and only lighten up your wallet, but some people suffer the illusion that if
they put 130 octane in their 8:1 compression engine, they'll gain 100
horsepower (I've seen that too many times).
<<There is a balance required, too slow a burn and the combustion
process is not complete when the piston gets to the bottom of
the power stroke(wasted energy)>>
Yeah, kinda. The nitro burners running a 90% load of nitro and roughly 20
pounds of boost have about 70 degrees of advance but make roughly 6000 hp and
still provide that spectacular light show coming out the exhaust. Doesn't
seem to bother them, although doing this with a gas engine might be
counterproductive. No war intended, just enjoying straightening out some
myths.
Michael
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