The term “muscle car” in its purest form pertains to stuffing a giant engine into a smaller car. Typically when this is considered, people think of older steel-clad American beasts prowling the streets with eight exploding cylinders crushing innocent ear drums. Muscle cars from the 1960s had hundreds of horsepower, a lot of weight on the front end, and even some had positraction, which was a kind of differential that sent some power to the wheel that wasn’t spinning, not dissimilar to today’s limited slip differential. Back then tire technology was nowhere near what it is today. Tires are more durable, last longer, and provide better steering, brakes, and traction than ever before. But for your 1970 Ford Gran Torino, which tire is best?
If you want to preserve the performance the car already makes, stick with the stock tire sizes. These are always written down in the owner’s manual, or the information is readily available with a five second google search. If you’re going to add more horsepower, you’re going to need bigger tires to handle it. More horsepower means the tires are going to spin that much faster, and unless you have a contact patch big enough to handle it, they will keep spinning.
Even if you decide to go for big tires, keep in mind the stock sizes. Oversized tires, or, tires that are too big for their wheels, run the risk of worse handling, rubbing (where the tire goes against the fender), and from a more technical standpoint, bigger tires will physically change the speed output. In other words, bigger tires have the effect of gearing up your vehicle where 1st gear performs like 2nd and so forth.
If you’re just going for wider tires, there’s a lot to consider. The width of the wheel itself and the clearance between the wheel and the fender both come to mind. And when you start considering bigger wheels to accommodate your big tires, in some cases the wheel might not clear the brake caliper. Of course, you can always go a bit wider, which won’t harm anything except gas mileage, but be sure you don’t go too much bigger.
If you’re one of those muscle car owners with a lot of horsepower under the hood, keep in mind that some tires are not street legal. For instance, racing slicks are not road legal. Toyo Proxes R888R tires, for instance, are street legal racing tires and are a good option if you have a lot of power you need to get to the ground.
No matter what though, you can’t go wrong with getting tires now for your older car. Sizes are pretty standard so you won’t have problems finding tires that fit, but also the technology has improved so much that any new tire will be an upgrade from what used to be available.
Avid Formula 1 fan and motorcyclist, I enjoy chocolate chip cookie dough ice cream and long rides to the beach.