Date: Mon, 8 Jul 2002 17:47:35 +0100
Reply-To: Clive Smith <clive.harman-smith@NTLWORLD.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Clive Smith <clive.harman-smith@NTLWORLD.COM>
Subject: Re: High elevation adjustments?
Content-Type: text/plain; charset="iso-8859-1"
Definitely turbo, but not a big one, unless you want to intercool, rather
than just restore sea level performance. Also, manual gearbox - definitely -
I think I'd shoot myself before buying another auto of that vintage, even in
the UK - as a race we tend to hate them. At least you could entertain
yourself by changing up and down now and again.
Ensure air-cleaner is spotless and can not pickup 'any' warm air from engine
bay. Check the plug colour, if it looks a bit dark or very light (unlikely)
after a plug chop (when you need to take a pee whilst climbing for half and
hour) then at least you know the altitude's not fully corrected for by the
injection. If its running at all weak, you will be losing power and remember
that weak mixtures take longer to burn, though the answer is not to
necessarily advance the ignition - correct the mixture if you can.
Reduce weight, the unnecessary crap I've seen onboard some vehicles, defies
belief. Turn off all unnecessary ancillaries.
Up the tyre pressures to the max for safety and handling. Try to reduce the
engine-bay temperatures by every means, there's an article on Vanagon site
about soundproofing, but this also talks about insulating the exhaust system
with something called F1 tape (I think) - keeping the heat 'inside' the
exhaust system achieves 2 things, extracts exhaust gases better (improves
cylinder scavenging) - more power, lower cyl. temps and reduces heat
transfer to the engine bay. I imagine the heat from the auto might be upping
the engine-bay temps too. Do all this and you might go from 30-35mph (with a
manual gearbox) - but thats what? 18%
At 10,00 ft air pressure is 78.8% and density (what matters) 73.8% of that
at Sea level, so you've lost 25% at least by then, remembering that what
matters is not absolute power, but EXCESS power, power available to do work
above and beyond just driving the ancillaries, gearbox, torque convertor,
alternator, etc etc. Any increase you can make will go directly to to
improving hill-climbing - in short, gaining 2 BHP at the engine will be
equivalent to gaining say, 2.5 or more at the wheels as these losses are
nominally constant. If you ever climb to an altitude where the vehicle won't
climb at all anymore - in that gear - then you can do a rough sum of the
horsepower consumed by the ancillaries and transmission (horrendous) -
density at 5,000' = 86.15% of sl
density at 10,000' = 73.8% of sl
density at 15,000' = 62.9% of sl
density at 20,000' = 53.3% of sl
Power will be approx. proportional to density (the number of molecules of
oxygen) provided cylinder filling holds up.
Nitrous Oxide anyone? Fuel additives, methanol?
Clive Smith
'88 Syncro Transporter 2.1
----- Original Message -----
From: "mike" <mwmiller@CWNET.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, July 08, 2002 4:55 PM
Subject: Re: High elevation adjustments?
> Turbo. Big one.
>
> > From: Andrew Fox <afox@CNR.COLOSTATE.EDU>
> > Reply-To: Andrew Fox <afox@CNR.COLOSTATE.EDU>
> > Date: Mon, 8 Jul 2002 09:34:11 -0600
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: High elevation adjustments?
> >
> > I routinely drive my van at elevations ranging from 5,000-14,000 feet
here
> > in Colorado. Above about 8,000 feet i experience loss of power such
that
> > I am only able to maintain about 30 mph while keeping the engine floored
> > in second gear. I know its a crime but i routinely drive my van with my
> > foot to the floor for a half hour or longer while going uphill in second
> > gear (auto tranny). So my question is are there any adjustments I can
> > make to have a better high elevation driving experience? Any Colorado
> > listees out there that can tell me if they get better or worse
performance
> > on some of Colorado's steep/high highways (ie I-70)? Going east up to
the
> > eisenhower tunnel on I-70 my max speed is about 30 MPH (second gear,
foot
> > to the floor, 2.1L, AT).
> >
> > Thanks,
> > Andrew Fox
> > 86 Westy
> > Ft. Collins CO
> >
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