Date:         Wed, 20 Feb 2002 11:03:46 -0800
Reply-To:     Paul Mayfield <paulmayfield@EARTHLINK.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Paul Mayfield <paulmayfield@EARTHLINK.NET>
Subject:      Re: Engine Wear
In-Reply-To:  <200202191916.16Dnfz2h53NZFlq0@merlin>
Content-type: text/plain; charset="US-ASCII"

Does anybody know how much horsepower
is required at 60mph vs. 70mph and 80mph?

Drag is Inverse to speed?

I'd like to know how much extra HP it takes
to push my shoebox at the speeds I enjoy.

My westy cruises very well at 70-75, ~4200rpm
and has no trouble at all doing 80.

Did VW engineers design for ~75mph cruising speed?

Paul '87 Westy w/ auto

----Frank Grunthaner's Response------

> Date:    Tue, 19 Feb 2002 21:45:22 EST
> From:    <FrankGRUN@AOL.COM>
> Subject: Re: Engine Wear

> Al,
>
> True as far as it goes. More details in a long soliloquy I put in the
> archives about a year ago on piston speeds. To summarize, the current
> materials set (post 1980 for VW/Audi) allows the choice of wall finishes,
> materials, ring surfaces and compositions such that continual operation at
> 5000 rpm with high loads (1 HP per cubic inch) will give a 75% wear point in
> 300,000 km. This is in contrast with a 75% wear point on a 1985 Ford V8 at
> 80,000 miles. The point is that the engineer designs for a load-wear-life p
> rofile. Now it is true that you can reduce the piston ring wear for the same
> engine by 20% by operating it at 4000 rpm vs. 5000. But not the whole story.

***Big Snip***

> Frank Grunthaner