<VV> EM spare space saver doughnut tire?

Tue Apr 7 13:04:24 EDT 2015

Ignacio,

I can't help you with a wheel selection but the topic of space  saver (SS) 
wheels has been discussed on VV.

Yes, there are benefits of both size and weight to the SS  wheels but there 
are other concerns of safety and performance.  First, the  general 
performance.  The SS wheel is likely to be a different size than  your existing 
wheel.  I guess that's a point of having an SS.  If you  have a posi rear, and 
you mount the SS on the back of your car, the different  diameters from left 
to right will cause wear on your differential.  Of  course, the damage will 
be related to the distance you drive.  If you have  your flat tire in the 
back and want to use an SS, I suggest you put a good wheel  from the front on 
the back and use the SS on the front.  This is not as  much an issue with 
"open" differentials.

Another issue is the hardness of the SS.  Generally, the  SS has higher 
inflation pressure and hardness of rubber as well as very minimal  tread.  This 
will diminish traction on the SS vs. the other wheels which leads me to 
safety issues.

SS wheels are "emergency only" devices on cars for which they  were 
designed.  If you have one available, you will see a big warning  sticker on it and 
for good reason.  They are intended only for limping  along at low speed 
for a short distance.  However, I think we have all seen  people with these 
wheels on the road driving at high speed and whipping around  curves.  They 
are tempting fate and endangering themselves and  others.  This is a 
cautionary note for people using SS wheels on cars for  which they were designed; not 
Corvairs.  I think we all know that the bad  reputation our Corvairs have 
for uncontrollable handling, flipping over, etc. is  undeserved.  For 
accidents that can't be attributed to "the usual" causes,  it is generally accepted 
that bad tire inflation and mismatched tires could  be major contributors 
to the accident.  Our Corvairs are more sensitive to  these wheel issues than 
other cars.  There can be no worse example of bad  inflation and mismatched 
tires than an SS wheel.  I can  describe the reasons the SS wheels are more 
dangerous on our Corvairs but I  think it is safe to say that SS wheels 
aren't safe, ESPECIALLY on our  cars.  Do you haul that much stuff that a few 
extra cubic inches of space  in your trunk is so important?  The minor 
difference in weight can't really  show up in your mileage significantly.  Yes, 
the car companies introduced  the SS for weight savings but mostly they use 
them because they are  cheaper.  The weight savings and mileage benefits of an 
SS are only  significant when combined with a multitude of other weight 
saving measures car  companies have designed in over the years.  Keep in mind 
that modern cars  have been designed to use SS wheels and those SS wheels 
were designed for use on  specific cars which are different from model to 
model.  SS wheels were  never considered in the design of our Corvairs.  If you 
get any responses  that tell you that someone has used SS wheels "without a 
problem" just consider  that some people have played Russian roulette 
"without a problem"  too.

Now I will extend this cautionary  note on tires generally.  How many of us 
have spare tires in their trunks  or engine compartment that are bald, (SS 
tires are pretty much bald from the  factory) have cracked sidewalls or are 
under inflated or maybe even  flat?  Even tires without cracks may have 
brittle sidewalls, etc.   Keep in mind that depth of tread is only one safety 
factor.  When we get  new tires, how many try to save by not buying that fifth 
wheel and using the  best of the bad tires as the spare?  Sometimes that 
same spare sits there  cooking in the engine compartment for many generations 
of replaced tires used on  the road.  Tires age even when they are not 
exposed to light.  Your  spare could be silently sitting in your trunk waiting to 
cause an accident when  used any time in the future.  The best bet is to 
have 5 good tires and  rotate them periodically as directed in your owner's 
manual.  That way, all  tires will last 25% longer and the cost of 5 
replacements instead of 4 will be  absorbed.  When rotating tires, pay attention to 
the inflation requirements  from front to rear and make adjustments.  Also, 
keep your spare inflated to  the rear pressure.  That way, when you have a 
flat, you can use it on the  rear at that inflation or on the front after you 
let some air out.

If you must use an SS wheel, use it with extra  caution.  Even if SS wheels 
were available in the 60s, GM Engineers would  NEVER have used them on our 
cars due to the peculiarities of the Corvair  design.

Drive safe.

Doc

PS: After this, I think I will go check the condition of my  many spare 
tires

'60 Corvette, '61 Rampside, '62 Rampside, '64 Spider coupe,  '65 
Greenbrier, '66 Canadian Corsa coupe, '67 Nova SS, '68 Camaro  ragtop
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In a message dated 4/7/2015 5:22:54 A.M. Pacific Daylight Time,  
virtualvairs-request at corvair.org writes:

Message:  8
Date: Mon, 6 Apr 2015 23:46:10 -0500
From: Ignacio Valdes  <ivaldes1 at gmail.com>
To: Virtual Vairs  <virtualvairs at corvair.org>
Subject: <VV> EM spare space saver  doughnut tire?
Message-ID:
<CANPWqJGjUA0OEeePuLsJ0jueByAaonw-ET_jvwmFGc4hxYV29w at mail.gmail.com>
Content-Type:  text/plain; charset=UTF-8

Hi, I would like to get a space saver tire  for a 1964. Which year and 
model space saver tire from newer cars will work  with the 4 hole pattern? --  IV