<VV> Overcooling (was: LM turbos and no lower shrouds)

[rbuckridge at comcast.net]

I'm really surprised that you could over cool the engine. 

When we were racing the Legends car, (yea I know it's different from a Corvair or that guy talking about racing Legends again), we could never over cool the engine. 

The engine was a Yamaha 1200 bike engine, by rule, that always ran with the oil temperature gauge pegged. (Guage read to 300°F) 

As in all racing, you make running changes looking for the best set up for conditions. We had removed all the gauges from the car in an effort to save ever ounce of weight and since the driver can't look at the gauges when running on a 1/3 mile oval. At the end of each session we would shoot the oil cooler, oil filter, oil pan, cylinder head and rear end gear to get an idea as to how hot we were running. 

Our best set up was a Fluid-dyne oil cooler, located so it received maximum cooling air and synthetic oil. Our best oil temps were still 190°F. We raced in all types of weather from 20°F to 95°F and the engine was always at maximum RPM. We had a 10,600 RPM limit by rule and we tried to stay off the rev-limiter because hitting the rev limit was like hitting the brakes, so I would say the engine was always running 9,000 to 10,500 RPM except under yellow flag conditions. We did change the oil and filter after every third race. 

I would also add that we never had an oil related engine failure. We put a ton of race laps on the engine and always had the engine rebuilt at the end of the season. 

Roy in Bayville 08721 

----------original message---------- 

Date: Tue, 25 Oct 2011 10:55:13 -0400 
From: Vairtec Corporation < Vairtec at optonline.net > 
Subject: Re: <VV> Overcooling (was: LM turbos and no lower shrouds) 
To: virtualvairs at corvair.org 
Message-ID: < 4EA6CDD1.6070606 at optonline.net > 
Content-Type: text/plain; charset=ISO-8859-1; format=flowed 

jvhroberts at aol.com wrote: 

> In my experience, overcooling a Corvair engine is just about impossible. And yes, mine had all the seals in place around the engine, etc. 

Well, there's your problem! [ Grin ! ] 

Back in my misspent youth I once created a Corvair engine that 
overcooled. I took too many things off! It was a stock 1965 140, fully 
deflashed, with not onl the lower shrouds removed, but also the front 
shrouds (the ones to which the lower heater hoses attach) trimmed to 
just the innermost piece, and the rear ducts (the door assemblies) also 
trimmed to just the innermost part. (These innermost pieces extend down 
to the midpoint on the cylinder barrels and heads.) 

Street-driven that engine NEVER reached operating temperature. Full 
front shrouds and rear ducts went back on it in relatively short order.