Date:         Wed, 23 Jan 2002 13:16:05 -0800
Reply-To:     harald_nancy <harald_nancy@EMAIL.MSN.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         harald_nancy <harald_nancy@EMAIL.MSN.COM>
Subject:      Re: '80 Westfalia-- best way to drive over passes
Content-Type: text/plain; charset="iso-8859-1"

I find this thread has become very frustrating.
Perhaps someone's tachometer needs to be recalibrated.
I had a '81 vanagon westy back when it was a pretty new car,
and drove it for many years.
I towed a 2,500 lb sailboat with it, even across the Siskiyous,
and the vanagon never gave me problems for 160,000 miles.
As mentioned before, the most important thing about
driving the aircooled vanagon is to keep the rpm up,
so the cooling fan is at its most efficient.
That means shifting down going uphills into 3rd, and sometimes
2nd, so the engine can rev at its most optimum.
Lugging the motor can be more damaging than revving it.
For the 2.0 liter air cooled vanagon, that means keeping
the rpm around 3400 to 3800. That's the truth.
If you don't believe it, check your VW specs.
That means if you climb a hill in 3rd gear, at about 45 mph,
your engine will rev somewhere around 3500 to 3800 rpm,
which is good. That's the way VW designed it.
Specs from original VW '80 brochure:
HP 67 at 4200 rpm. (revving any faster will get you into a black hole)
Top speed 75 mph (that would be about 4200 rpm)
Max Torque 101 ft. lbs at 3000 rpm (above 4000 rpm, the torque
just disappears).

Btw, there are many different Type 4. There was the 1700 bus,
which behaved quite differently than the 2.0 liter Type 4.
Also the Porsche 914 Type 4 engine is built to rev higher than
the Vanagon Type 4.
Harald
'90 westy

----- Original Message -----
From: "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, January 23, 2002 4:26 AM
Subject: Re: '80 Westfalia-- best way to drive over passes


> I'm left more confused about Stan thinks than when I started. Was he
> confirming or refuting my thoughts? Not sure.
>
> First off, I was talking about all Type 4 motors, 1968-1983.5,
> particularly when in use in the Vanagon 1980-1983.5. Second, redline on
> the type 4 is 5600, not 5000. I've routinely driven at or near 5,000 for
> hours on end (on cross-country jaunts) with no issues or problems. This
> is Type 4 vehicle #8 for me, and only one motor failure (at 135k due to
> low compression)
>
> This whole notion that the "ENGINE ACCUMULATES HEAT OVER TIME" is nuts.
> If it were true that THE ENGINE ACCUMULATES HEAT OVER TIME in some sort
> of linear progression, every long trip would end in a meltdown.
>
> In actuality, once your motor reaches operating temperature, the engine
> is constantly shedding heat. With its deep fins, alloy construction,
> oversized fan, and huge oil cooler it has a finite capacity for shedding
> heat, however, that capacity exceeds common usage by a wide margin.
>
> Since the only two moving parts of the cooling system (oil pump and
> cooling fan, except the thermostat) are crank driven, cooling capacity
> increases as crank speed increases, in relatively direct proportion. At
> a certain point, (somewhere around 4800) you reach the point of
> diminishing returns, no additional cooling air forced through the system
> will shed any additional heat due to laminar flow and molecular
> shielding constraints [ a thin layer of immobile air molecules forms
> adjacent to the metal cooling surfaces preventing additional heat
> shedding even with additional air flow].
>
> Even on the hottest summer days, I have crossed the southern USA with 5
> people and a full load in a van and had no problems, we simply didn't
> try to go 70 mph, or climb hills in 4th. We stayed below 5k, and just
> plugged along.
>
> It is only when the driver places an exceptional load on the engine
> (full throttle under heavy load), while keeping the cooling system in a
> sub-optimum range (i.e. 3,000-4,000 rpm) that heat builds up. The crank
> speed is insufficient to push enough air across the cooling surfaces to
> displace the heat; only then does "engine heat accumulate over time".
>
> No-one proposed going 70mph in 3rd, as Stan suggests. What I said was
> reduce your speed to 45 and relax in 3rd at 45mph for the climb (which
> Stan also say he has done??). Again, this puts the cooling system at
> peak capacity, while at the same time reducing the load on the
> crankshaft.
>
> From historic, walkable Mount Olive, NC,
>
> G. Matthew Bulley
> Bulley-Hewlett
> Corporate Communications
> Business: www.bulley-hewlett.com
> Alliance: www.ntara.com
> Home: www.MountOliveNC.info
>