Date: Sun, 23 May 2010 07:33:15 -0500
Reply-To: mcneely4@COX.NET
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dave Mcneely <mcneely4@COX.NET>
Subject: Re: Optimum WBX rpms; was RE: 4 speed/5 speed shifter
In-Reply-To: <01c001cafa1c$100769b0$6401a8c0@PROSPERITY>
Content-Type: text/plain; charset=utf-8
Pardon my naivete. I thought the production of heat by work effort was simple physics. When I work harder, I get warmer and sweat more than when I work less hard. I believe the same is true of machinery (except for the sweating part). The heat is the part of the force applied that isn't turned into productive work. To the degree that that is true, wouldn't whatever materials were in contact with the parts developing the heat themselves become hotter -- including oil. We hope that most of the heat is collected into the coolant and dissipated via the radiator of course, but there is definitely a time lag in this. Not true?
David
---- Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM> wrote:
> hmmm,......could be.
>
> I don't see why increased windge from higher rpm in top gear would raise
> oil temps.
> Windage may be one factor in dry sump engines...and
> for many performance cars the primary purpose is to lower the engine as far
> as possible in the chassis, lowering certer of gravity for better handling.
>
> Be interesting to see what Frand G says on the subject,
> and I'm sure he has posted on oil temps somewere in the past.
>
>
> ----- Original Message -----
> From: "Dennis Haynes" <d23haynes57@HOTMAIL.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Saturday, May 22, 2010 6:41 PM
> Subject: Re: Optimum WBX rpms; was RE: 4 speed/5 speed shifter
>
>
> It does. Even with high capacity oil coolers I see the oil temp increase at
> higher speeds over time, even with the water temp staying normal. Most
> likely the problem is the increased windage from the rotating parts sitting
> in the oil. This is why many race engines run dry sumps.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Dave Mcneely
> Sent: Saturday, May 22, 2010 7:56 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Optimum WBX rpms; was RE: 4 speed/5 speed shifter
>
> ---- Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM> wrote:
>
> > I do not see any reason why 4,200 rpm would produce particularly higher
> > oil
> > temps than 3,800 rpm would.
> > other than slightly increased load due to speed and aero drag ...
> > I see no reason especially why oil temps would be higher with a bit more
> > rpm.
> > Scott
>
> Scott, maybe it's the slightly increased load.
>
> David McNeely
--
David McNeely
|