It's not the compression that decreases with altitude, it's the density.
Boosting the compression ratio gets the pressure back up but on a smaller
volume (sort of like running a smaller engine). And certainly not practical
for riding up and down mountains. The only real solution to this altitude
problem is super or turbo charging & we've been through that discussion many
times before.
As for re-chipping the GTS, GFL! If you find a way, many others are
interested also. WE've been through that discussion too many times already
also.
Bill
-----Original Message-----
From: [EMAIL PROTECTED] <[EMAIL PROTECTED]>
To: Multiple recipients of list <[EMAIL PROTECTED]>
Date: Tuesday, September 19, 2000 9:32 PM
Subject: Re: GTS to FZR stuff
>In a message dated 9/19/00 5:17:52 PM Eastern Daylight Time,
>[EMAIL PROTECTED] writes:
>
><< I take my bike into the Mountains
> frequently and once above 6000ft or so it starts to lose a significant
> amount of power. It seems an exhaust would help this, I'm also looking
into
> re-chipping the bike if any one has any experience with that. >>
>>From watercraft racing, and taking boats from Fl to denver, it is not the
>exhaust that is killing you. It is lack of compression. In thinner air, you
>are just not getting as big a bang inside the cylinders that you do at
lower
>altitudes. The problem is not evacuating the cylinder, it is getting a more
>powerful explosion. The watercraft race engines run the same exhaust, but
>higher compressions to compensate for the altitude. There is some rule of
>thumb formula that escapes me now, mainly because I live in Florida and it
>doesn't apply, but something to the effect of 10~15% decrease in HP per
3000
>ft. Your stock exhaust still flows fine at altitude, it just doesnt have
>enough to flow through it. This gets back to the engine flow balance
theory.
>You can have an exhaust that flows 200 CFM, but if the head or intake only
>flows 100 CFM, that will be your bottle neck. Increasing the exhaust to 300
>CFM will not produce anymore horsepower because it was not the limiting
>factor.
>
