<VV> turbocharger cooling

[Dave Thompson]

I forgot to mention earlier, I DO realize that there is a difference between
cylinder head temp, oil temp and turbo temp but they ARE related. I also
know that CHT changes faster than oil temp. I don't know about turbo temp. I
would imagine that it follows oil temp to a certain degree (no pun
intended). I also guess that turbo temp is mostly affected by exhaust temp
but is regulated by oil temp as the oil runs through it to lubricate the
bearings. Since I only have a CHT and the temps are rather stable with
driving style around 375 to 425, I use it to determine the overall temp of
the engine. Am I right in my assumptions?

Dave Thompson

-----Original Message-----
From: Dave Thompson [mailto:dave.thompson at verizon.net] 
Sent: Wednesday, May 27, 2009 9:45 PM
To: 'HallGrenn at aol.com'; 'JVHRoberts at aol.com'; 'FrankCB at aol.com';
'shortle556 at earthlink.net'; 'fparker at umich.edu'
Cc: 'virtualvairs at corvair.org'
Subject: RE: <VV> turbocharger cooling

OK,
I have a 63 Spyder clone with a 64 drive train. I'm on my third thermister.
Each one read slightly different on the CHT instrument so I know that the
CHT instrument is not totally accurate. With that in mind, On surface
streets, I currently indicate about 375 degrees. After a minute or two at
freeway speeds it raises to about 425 degrees. I have never seen it get any
higher than that. When I come off the freeway, it comes back down after a
minute or two of surface street driving. If the CHT is above 375, I let my
engine idle until CHT is around 375 before shutdown. However, if I drive for
a few blocks and the CHT is at 375 or below, I just shut down when I stop. I
use my CHT to determine if I need to idle before shutdown. Of course, if I
had just jumped on it to get some boost, I let it idle or drive moderately
for a few blocks before shutdown.

With the string that is going on here I wonder if I should idle for a minute
or so before every shutdown. What are you guy's opinions on my current
procedure? Should I modify it? If so, How?

Dave Thompson
36 Spyder vert
Westminster, CA