<VV> Tired of tires?

[Bruce Schug]

I think a 205/60 is a nice size for a street Corvair. It is, however, 
smaller in diameter than a stock 7.00-13. The 205/60 is 
(mathematically) 24.69" in diameter whereas the 7.00-13s were closer to 
25.3 or so.

Your '66 speedometer should be calibrated for 825 rpm, although it 
won't be accurate at that rpm because they weren't accurate as shipped 
by GM. But, if you want a tire that is "matched" like a stock tire, 
look for 825 rpm. You'll really have to look over some tire specs to 
find what you're looking for. As you look over the tire manufacturer's 
specs, pay attention to whether or not they measure the rpm's standing 
still or moving. You'll be more accurate to find one that's measured 
moving, typically at 50 mph.

An 825 rpm 15" tire might not be easy to come by. Look at 205/65's. 
Some might be tall enough. You might end up with a 215/60 which just 
looks too "big" for me ("big" being defined as a combination of width 
and diameter). But depending on their construction, that's about where 
you'll be.

Now if you really want the speedometer to be accurate you might want to 
shoot for a rpm of closer to 840. This is easier to come by. Despite 
its smaller-than-stock diameter you might find a 205/60 that is 840 
rpm. You might have to go to a 195/65. It just depends on the 
construction.

If it were me, I'd probably get a good set of 205/60's and then if the 
speedometer wasn't close enough I'd get a converter for it.

Good luck. I'd be interested in knowing what you end up with and why.

Bruce

On May 24, 2004, at 5:02 PM, Robert Marlow wrote:

> One of the perennial threads on VV is, "what size tire fits my car?"
> Today, it's my turn.
>
> I already have the wheels and my own idea of what the ideal tire size 
> is.
> But I am interested in the opinions and experiences of others.
>
> The wheels are 15x7.  The car is a '66 coupe.  The goal is a
> speedometer/odometer that is reasonably accurate.  For general highway 
> use,
> so don't worry about specific tires that are suited for autocross or 
> racing
> or the like.
>
> And, for those who may wish to point me toward Bryan Blackwell's site, 
> it
> is one of the sites I have visited already and it has influenced my
> thinking thus far.
>
> --Bob
>
> Robert W. Marlow
> nortechcorp@optonline.net
>
Bruce W, Schug
CORSA South Carolina
Greenville, SC
bwschug@charter.net

CORSA member since 1981

'67 Monza. "67AC140"