Date: Sat, 21 Nov 1998 20:43:04 -0500
Reply-To: Mark Rokus <marokus@VOYAGER.NET>
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Mark Rokus <marokus@VOYAGER.NET>
Subject: Re: simple engine RPM question--need shifting advice
Content-Type: text/plain; charset=us-ascii
I guess its time to enter the fray....
For some masochistic reason, I have always owned under powered vehicles
(with the exception of a RD 400 Yamaha). Beetles, gas and diesel
rabbits, a 411, Busses, and now Vanagons. I have always reasoned that
these things had to fight for their life on the Autobahn, and thus could
probably take it. Other than the usual broken valves on air-cooled bus
motors, I have had no failures resulting from sustained high revs. I
have always rebuilt my own stuff and usually don't even buy anything
before it had 100,000 miles. The last engine I have baked was a '73 411
motor that had been in 3 busses after the car. It was in my '81 Westy
with a re-welded junkyard crank. I had about 70,000 miles on that crank
after the re-welded journal and only scorched it because of an oil leak
that I didn't care for. I wouldn't recommend sustained 5000 rpm while
down a couple quarts, but if properly balanced, carefully built, and
faithfully nourished, I don't hesitate to bump my 5400 rev limiter on
air cooled's. On Waterboxers, I have seen even less need to nurse them
as they basically run out of power when you rev them too high. I have
driven basically as fast as the vans felt comfortable. Sometimes that
meant with wide open for hours through the mountains, sometimes just
cruising at 85 mph. I have seen Rabbit motors turn 7500 rpm on a dyno
with nothing more than high quality rod bolts and shot peened stock
rods. Basically, if the valves don't float, and there is good clean oil
in it, my experience it that you are likely not hurting much. Obvious
disclaimer applies if previous owner put 100,000 miles on it and never
had it above 3000 rpm.
(GMBully, I know this must pain you but that's been my experience)
....let the FLAMES Begin!.....
Vanman wrote:
> ... My point is that, the green zone is a reccomended guideline, but
> as long as there is a hard load on the engine, don't be afraid to rev
> it to 5000 (which is 200 below the orange zone) and keep it there a
> few minutes. This will probably draw some flak, but oh well. -Aaron
> Mckay mckayaa@oit.edu
> college student in
> mechanical engineering at Oregon
> Institute of Technology
> '85 vanagon GL
>
> -----Original Message-----
> From: Phillip Bouton <pbouton@NACCHO.ORG>
> To: vanagon@VANAGON.COM <vanagon@VANAGON.COM>
> Date: Friday, November 20, 1998 6:54 AM
> Subject: Re: simple engine RPM question--need shifting
> advice
> I also have been perplexed by the same issue. The manual
> says to stay in the green. On my 87 Westy that is between 2
> and 4k rpm. Europeans would rather sacrifice an engine to
> save gas in the long run because gas is so expensive. In my
> van it seems that in order for the next higher gear to start
> around 2k, you definitely need to be shifting around 3500 or
> higher. Otherwise the next higher gear will be between 1.5
> and 2k. However, I can't say that I do this consistently
> because it is so hard to let myself rev the engine that high
> in the lower gears. Does anyone have any reassurances or
> other comments?
>
> ><><><><><><><><><><><><><><><><><><><><>J
> Phillip Bouton
> -----Original Message-----
> From: Jarod Bishop [mailto:jbishop01@FOXINTERNET.NET]
> Sent: Thursday, November 19, 1998 7:38 PM
> To: vanagon@VANAGON.COM
> Subject: simple engine RPM question
>
> I recently bought an '87 Syncro. Having never owned a VW,
> I'm not used to
> running the engine at a higher RPM rate like people have
> told me.
>
> The speed seems to max out at around 3500 but I give some
> more gas and get
> it past 4k before shifting, but I've heard you should go
> atleast 4.5k or
> 5k. I was hoping to get input on what others typically run
> their vans at
> before shifting up.
>
> Thanks
>
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