Date: Thu, 12 May 94 09:26:14 CDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Joel Walker <JWALKER@ua1vm.ua.edu>
Subject: vanagon: turbo-diesel in america
ha! gotcha with that catchy title, didn't i? well, i was looking for some
stuff on a bmw isetta, and ran across this stuff:
............................................................................
VW Autoist, March/April 1987, page 24-25.
The Oil Burner (column by Roland Walkenhorst)
...
Henry F. Dunlap of Wimberley, Texas, is another guy who was dreaming last
year of owning a turbo-diesel Vanagon. Henry had an advantage, though. He
already had a naturally aspirated 1982 diesel Vanagon camper when he got
the idea that a blown oil burner might haul a van around quite nicely.
"The camper is great," he wrote, "but the diesel engine doesn't give it
enough power to accelerate safely in some situations, such as getting onto
freeways or in critical passing situations."
Henry explored several possibilities, including adapting the VW parts from a
late-model factory-turbocharger diesel. He eventually settled on a turbo
kit from Arkay Engineering (15828 South Broadway, Gardena, Calif. 90248).
This is the same company from which I once bought a turbo kit for my 1978
Rabbit diesel.
The kit cost $2,100, not including installation, compared with less than
$1,000 for my Rabbit kit in 1979. I was a little surprised at the big
increase in cost until Henry sent me the details of what the new Vanagon
kit includes that mine didn't.
The most important addition is an air-to-air intercooler, a small heat
exchanger that cools air from the turbocharger before it enters the
combustion chambers. Intercoolers, mostly the water-to-air type, have been
used for ages on truck engines but have just recently become popular for
cars. A turbocharger's compressing of the intake charge makes the air going
into the engine very hot. Cooling the compressed air by routing it through
the intercooler results in a denser charge and increased efficiency.
Also included in the new kit is a trap that catches oil from the cam cover
breather and lets it drain back into the oil pan. The oil would otherwise
collect inside the air cleaner where the oil-laden air from the breather
ren-enters the engine. My Rabbit kit just routed this breather hose into the
intake pipe connected to the turbo. Oil blown out the breather would run
down and leak out where the pipe connected to the compressor housing,
resulting in a little oil puddle everywhere I parked. It look like Arkay
has found a good fix for this problem.
The Vanagon kit also includes a new muffler and mounting hardware.
Instrumentation is more complete than it was in my Rabbit kit. Henry's kit
includes both a boost gauge and a pyrometer, an instrument that measures the
temperature of exhaust gases coming out of the engine. Mine had just a boost
gauge. Since high exhaust temperature indicates that the engine is being
pushed so hard that fuel is continuiing to burn after it leaves the cylinder
-- an inefficient and possibly damaging situation -- the pyrometer can help
the driver refine his driving style to get better efficiency and engine
longevity. Pyrometers are used extensively in trucks for that reason.
Henry is well pleased with the workmanship and performance of the kit so far,
although he had some trouble with delivery. It took two months for the kit
to arrive and when it did, three heat-resistant silicone hoses for the intake
plumbing were missing. After numerous phone calls to Arkay resulted in
unfulfilled promises to ship the missing parts by UPS air, Cal Triesch of
Crestwood Motors in San Marcos, Texas, the mechanic who installed the kit
for Henry, gave up hope of getting the parts. He made do by using the
silicone hoses that did come with the kit for the hotter parts of the
installation and conventional radiator hose for the rest.
Next time we'll get into some of the details of installing the turbo kit on
the Vanagon.
...........................................................................
hmmmm. i didn't see any follow-up article in that same year. well, if anybody
wants me to, i'll go back and look more closely. however, this article
was in the next year, VW Autoist, July/August 1988.
...........................................................................
Vanagon Turbo Revisited
It's been more than a year since we last checked in with Henry Dunlap, the
proud owner of an aftermarket turbo diesel Vanagon in Wimberly, Texas
(March/April and May/June 1987 Autoist). As he promised, he's kept in touch
with occasional reports of the boosted van's performance. He's also added
an air conditioner to cope with the long Texas summers. I'll let Henry do the
talking:
"We sneaked away for three days and took a trip in the van to Rockport-Port
Arkansas area of the Gulf Coast. The van performed very well, I thought,
both in the hill country and in the flat coastal plain. You have to drive
with more of an eye on the pyrometer than the speedometer, as the temperature
can quickly exceed the 1,200-degree limit while going up a hill if you don't.
Letting up on the accelerator or downshifting drops the temperature quickly.
The 'feel' of the van is definitely improved by the turbo. It's certainly
not a hot rod now, but it's not a turtle either. Fuel economy was good --
26 mpg driving at around 55 mph on the 460-mile round trip. I couldn't
detect any oil usage.
... <and some stuff about the newly installed air conditoner>
..............................................................................
well, anyway, i thought it might be interesting to see that someone had
already done it. :)
joel
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