There are drag radials, available in lots of sizes. I run them on my 55 chevy when I go racing, they work fine on the street and are DOT approved. I had them on the car for 3700 miles when I went on Drag Week a couple months ago. There are also "cheater" slicks, usually with two grooves in them. Legal and safe are not always the same thing, though. Also without knowing a lot more about the ranchero it's pretty hard to say for sure that the size you need is available. What size tires are on it now?
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