Date: Wed, 26 Aug 2009 14:18:21 -0400
Reply-To: Marc Perdue <mcperdue@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Marc Perdue <mcperdue@GMAIL.COM>
Subject: Re: Engine to auto-tranny match and the Indy 500
In-Reply-To: <20090826172912.5511A1165C1@hamburg.alientech.net>
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Good points. Anybody on the list know what the horsepower rating is
of Bob Donalds' big valve engines is? That's what I'm running, not
stock . . . I suppose I should have said that earlier . . .
Regarding running behind semis, it was my understanding that doing so
would affect the airflow across the cooling system and make it more
likely to overheat. Given the Vanagon's "natural" tendency to do so
on a good day (joking), this doesn't seem like a good idea. Having
said that, I suspect that this effect would be fairly minimal over a
short period of time, less desirable to do over a great distance.
Marc
On Wed, Aug 26, 2009 at 1:28 PM, Mike S<mikes@flatsurface.com> wrote:
> At 12:27 PM 8/26/2009, Marc Perdue wrote...
>>
>> Is there any kind of automatic transmission alternative that could take
>> advantage of the torquey (technical term again) Vanagon engine
>
> Acceleration and holding speed up a hill are all about horsepower. An
> engine's torque numbers are only useful as a rough indication of how wide
> it's (horse)powerband is, and even then, only when considered in relation to
> it's HP numbers.
>
> A transmission can be made to give as much output torque as you want, it's
> just a matter of gear ratios - but more torque = lower speed. HP remains
> constant through a transmission (neglecting frictional loss). More gears in
> a transmission allows one to keep the engine running closer to it's maximum
> HP output, for better performance.
>
> The comment you responded to was in relation to the scarcity of
> transmissions to handle more powerful engines which have been adapted to the
> Vanagon.
>
> For the stock engines, VW engineers designed the gear ratios (and shift
> points) for the best all-around performance and reliability, given the
> available engine power. The stock 90 HP simply won't push a Vanagon through
> mountains at 65 MPH, no matter what you might change in a transmission.
>
> When going uphill, I just get behind a semi going 45, and enjoy the journey.
> If you're in a hurry, a Vanagon with a stock engine isn't a good choice.
>
>
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