<VV> LM turbo's and no lower shrouds

[kevin nash]

 Eric- I think your head temps have alot to do with you being at a higher elevation than others. At 8000 ft, the dynamic compression ratio of your engine is approximately 1.5 points lower than at sea level, which would make your engine run cooler compared to sea level operation. Also, the carburetor, because it is getting less air, but the jetting didnt change, gives the engine a richer mixture at altitude, causing the engine to run cooler than it normally would. I do live at sea level, and have a early turbo and know others with early turbo's, and can assure you, 430 degree's cruising down    the freeway at 70mph during the summer temps of 80 degree's IS fairly normal, unless you do something about it.  Kevin Nash
> > -----Original Message-----
> > From: virtualvairs-bounces at corvair.org
> > [mailto:virtualvairs-bounces at corvair.org] On Behalf Of Eric S. Eberhard
> > Sent: Sunday, October 23, 2011 2:29 AM
> > To: virtualvairs at corvair.org
> > Subject: <VV> LM turbos and no lower shrouds
> > 
> > 
> > 
> > I am always puzzled by this discussion which comes up every so 
> > often.  The car was designed well from the factory.  If you have 
> > everything correct -- all the shrouds as well as seals and so forth, 
> > there is no better system.  I am in AZ, totally bone-stock, at 
> > altitude (3500-8000 feet), summer temps of 110 ... and I NEVER have 
> > even gotten remotely close to overheating.  Our speed limit is 75 and 
> > I can go up a 6% grade at 80, no over heating.  From my 3500 to 7500 
> > feet happens in 6 miles, no overheat even at 80.
> > 
> > I believe that those that overheat and think they need to 
> > remove/modify shrouds simply have other problem they are compensating 
> > for.  Mine is a 62 EM and perhaps it is different, but I have had to 
> > EM turbos as well and neither ever had a heating problem.
> > And we get 20 degrees in the winter, so having those shrouds on then 
> > is crucial and I don't need the hassle of swapping them on and off.
> > 
> > One writer pointed out the correct heat is required for quick 
> > boost.  Correct.  Some people even wrap their exhaust to push temp 
> > even higher, for that reason.  Some people mistakenly use a "free 
> > flowing" muffler which actually reduces boost and is bad.  I used an 
> > NOS turbo muffler.
> > 
> > Keep it stock and it will be absolutely reliable (my only mods are 
> > electronic ignition and related upgrades).
> > 
> > If you have heating problems -- are your plugs too hot?  I use Nology 
> > Silverstone plugs and they perform very well with a 38 gap and hot 
> > ignition, no overheating.  They are made for vintage cars.  They are 
> > expensive, but I have over 30k on them and they are clean as a whistle.
> > 
> > BTW -- opinions are like belly buttons and so I have one.  I respect 
> > others, as other people have done neat things.  I am not a good 
> > enough amateur mechanic to re-engineer things.  But I believe a 
> > properly set up stock system -- not all that hard to achieve -- is 
> > going to be reliable.  Doing the ignition and putting a Judson on one 
> > of my cars is sort of the limit of my explorations.  However, my 
> > Spyder always has instant boost (no lag), boosts at 2000 rpm in 4th, 
> > pulls to redline, and I can't overheat it.
> > 
> > So if you are in the mood, you might try making it factory spec 
> > first, seeing how that goes, and then modify.  Otherwise, you might 
> > mask a problem that later gets ugly.
> > 
> > Eric 
> >