<VV> turbocharger cooling

[Dave Thompson]

Tim,
I changed thermisters because the first three failed. [SMILE] As for "turbo
temp" I meant the temp of the bearing and oil in the housing. The subject is
cooling the turbo. I twisted the subject to include cooling at shutdown.
Sorry I wasn't clear but you make good points. 

As I understand it, wrapping the exhaust going TO the turbo keeps the gasses
hot and flowing better thus giving sooner and more boost. I also understand
that unless the pipes are coated, they don't last as long.

Dave Thompson

-----Original Message-----
From: shortle [mailto:shortle556 at earthlink.net] 
Sent: Thursday, May 28, 2009 7:59 AM
To: Dave Thompson; 'Dave Thompson'; HallGrenn at aol.com; JVHRoberts at aol.com;
FrankCB at aol.com; fparker at umich.edu
Cc: virtualvairs at corvair.org
Subject: RE: <VV> turbocharger cooling

Hi Dave, I'm assuming you have changed the thermister 3 times thinking it
was not reading accurately. I don't think any of them were very accurate,
just an indication of what was going on. Oil temp. was never actually
monitored or checked on Corvairs though they (Chev.) knew it was an issue,
hence the engine oil cooler with suggested cooler maintenance (removing
cooler cover and cleaning fins). You mention "turbo temp.". Are you
referring to exhaust temp. at the turbine shaft, charge air pressure temp.
going into the intake crossover, or temp. of the oil at the center section?
I remember there being kits to wrap the exhaust pipes going up to the turbo.
I think it was to get quicker boosting (less lag) and less warm up time but
I'm not sure.
Timothy Shortle in Durango Colorado 

-----Original Message-----
>From: Dave Thompson <dave.thompson at verizon.net>
>Sent: May 27, 2009 11:32 PM
>To: 'Dave Thompson' <dave.thompson at verizon.net>, 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
>
>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
>
>
>