<VV> Fuel Economy

[BobHelt at aol.com]

In a message dated 12/29/05 6:25:03 PM Pacific Standard Time, 
brentcovey at hotmail.com writes:

> I'd driven Corvairs exclusively for a 15 year period, had 38 so far, and 
> theres been one in our family garage since 1972 and feel the general results I 
> have seen are readily obtainable for the average person under similar 
> circumstances.

Hi Brent,
Thank you for your very detailed and informative explanation on your gas 
mileage experiences. I know that it took quite a bit of time to state your 
position and explain how you arrived at those mileage figures.

I must however point out the other side of the Corvair's gas economy picture. 
Starting in 1960, car magazines started reporting their mileage figures 
obtained during their testing because the Corvair was treated as an economy car. In 
later years, the emphasis shifted more to performance and fewer mileage data 
were taken. But it seems logical and entirely correct to assume that the 
mileage obtaind with 145 cid Corvair's would be better than later years which had a 
larger displacement and more rated horsepower. (i.e., from 145 to 164 cid and 
80 (or 102) hp to 110)).  So what I'm saying is that LM Corvairs are likely 
to get poorer gas mileage than EMs.

But before I start listing some data, I want to address your following 
statement……

All the figures I mention have been converted from Imperial gallons to US 
Gallons using the 6/5ths formula.

There may be a problem here. And if so, maybe that could change everything. 
As far as I know, there are 4 quarts to the US gallon and 5 qts to the Imperial 
gallon. Isn't this correct? 

And isn't it also correct that your Corvairs all had US 
speedometers/odometers?

So wouldn't the correct conversion formula be = to

US miles / imperial gallons X 4/5  ? 

If your odos measured distance in KM then shouldn't the conversion be

KM X 5/8 /imp gal X 4/5 ?

Or do I have something screwed up here? (very possible)


OK, now for the data…………

Motor Life Mag reported the results of the 1961 Mobil Gas Economy run in the 
5/61 issue. Don't know the specifics of the Corvairs run, but the Corvairs got 
27.03 and 26. 22 MPG. Now considering that this was a mileage competition, 
the drivers were using all the tricks in the book to increase mpg and they only 
got 26 and 27.

Car Life mag reported the 1962 Mobil Gas economy run results in the  7/62 
issue. The top Corvair got 27.02 mpg. 

We don't know the speeds run for these tests, but again this was the BEST 
that drivers could get using all tricks that they could.

Consumer's Bulletin (similar ri Consumer's Reports) reported a mpg of 23.5 at 
a constant 50 mph in the 5/63 issue for a 1963 102hp/3.27. That's 50 mph so 
at 60 the mileage would be less.

Consumer's Reports reported the following:

8/64 issue  1964 110/3.27  24.0 at 60 mph and 16.8 in traffic (city driving?)

3/66 issue   1966 110/?    22.5 at 60 mph and 16.0 in traffic


Popular Mechanics reported the following in their 5/65 issue:

21.43 mpg at 60 mph, 1966 110hp/?


So you see that the typical gas mileage numbers were much closer to 22-24 mpg 
at 60 mph speeds. Maybe the mileage got much better at 50 or even 40 mph, but 
60 mph to me represents a more reasonable speed for determining gas economy. 
In fact, today's gasoline may actually lowere the mileage of a stock Corvair.


Remember that these were all cars fresh from the factory and all set to 
factory specs. Corvairs in use today, may have many worn parts and mal adjusted 
component which could lower mileage measurements made today. And I don't think 
breakin would be a factor either as the Corvairs came ready to run from the 
factory. Look in any Owner's Manual and you will see that there is no formal 
breakin schedule. It just says not to run at any speed for an extended time.


Regards,
Bob Helt