Tires: Speed Ratings, speed tires, technological leap

Question
My Supra turbo calls for, I think, "V"-speed tires. Back when I bought it, the car was 20 years younger than it is now -- and so was I -- so it made some sense to be able to go 150 (or whatever) mph on its tires. But now both the car and the driver are a LOT pokier, and now it rarely even approaches the speed limit. And nobody else will ever drive it.

So do I still need high-speed tires?  Is there something about a fast tire that's important for this car besides its ability to speed safely?

One dealer (either consciencious or supersilious) said he'd not sell me tires with a lower speed rating than called for by Toyota, whereas others were happy to sell me slow rubber -- what's with all that?

Thanks!  

Answer
Alan,

As time has gone on, it has been discovered that speed ratings aren't quite as accurate a gauge of the speed capability of a tire as once thought.  Things such as using a lower inflation pressure or age lowers the ability of a tire to withstand speed.

Plus, our litigious society has forced many retailers to adopt "safe" positions in order to prevent lawsuits.  This is one of those areas.

But you should be aware that there is more to speed ratings than just speed.  Higher speed rated tires are generally better handling - grippier and more responsive.  And the springs, the sway bars and shocks were all set up with this in mind.

I think you need a higher speed rating - maybe not a V but an H for sure.  Besides, an H rated tire is a HUGE technological leap up from an S or T and that makes it a safer tire for the buck.

Hope this helps.