New Shoes for the Cadillacs

The tires on my 1967 Cadillac deVille dated back to 1994. They still looked good, but they were far too old to be safe, so I avoided longer trips and higher speeds. It was time for some new shoes.
The Search for the Right Stripes
This time I wanted to go with bias ply tires, but the correct two-stripe bias ply tires for the ‘67 are not available. The correct tires for the ‘66 are, though, and they have three white stripes. So I came up with a plan: take the Diamond Back radials off the ‘66 and mount them on the ‘67, then buy the correct bias ply tires for the ‘66.
Looks Over Handling
The new tires were not exactly cheap, but I chose them mainly for the correct looks, and the difference in appearance is huge. Everybody recommended radials instead, since they drive so much better. Still, I went with the correct tires this time, because the ‘66 is such a low-mileage time capsule. I don’t drive it very often, so the less modern handling should not be much of an issue.
Bias Ply vs. Radial: What to Expect
If you are wondering what the fuss is about, here is how the two types compare.
Bias ply tires are built with layers of cord running diagonally across the tire, which is how every tire was made when these cars were new. Their biggest advantage is authenticity: the sidewall shape, the look of the tread and, of course, the correct white stripes. They also tend to have tough, forgiving sidewalls that stand up well to curb scuffs, and they give a soft, comfortable ride at moderate speeds, just as the engineers of the time intended.
The downsides are real, though. Bias ply tires wear faster, run hotter at sustained highway speeds and have more rolling resistance. They tend to wander and follow grooves in the road, they grip less in corners and in the wet, and they need longer to stop. They are also more prone to flat spots after long storage, which is something to keep in mind for a car that spends the winter in hibernation. And they need a bit more attention to tire pressure.
Radial tires, with their cords running straight across the tread, are better in almost every technical respect. They last longer, run cooler, hold the road better, brake shorter and handle wet roads with much more confidence. On the other hand, they look different from the originals, can be a bit firmer in ride and may feel heavier when steering at parking speeds on cars with older steering systems. Good radials in classic sizes with whitewalls are not cheap either.
For a car that sees regular highway miles, I would honestly recommend radials. For a pampered show car like my ‘66, I accept the trade-off for the sake of originality, and I simply drive it accordingly.
A Wheel Weight Goes Missing
I really enjoyed the first miles on the new tires and took the car to a local car show. On the way home, one of the wheel weights fell off. The tire shop had not attached it properly, so I had to pay them another visit.

At a local car show with the new tires.

Correct looking tires.

Tags:Tires, Bias Ply, 1966 Cadillac Coupe deVille, 1967 Cadillac DeVille, 1966, 1967, Low Mileage, Time capsule, Parts, Repair, Car Show, 1967 Cadillac DeVille, Low Mileage