No one is arguing. You are reiterating my point. I told him to go to the tire dealer and have them check it out because every car is different. Some have been in accidents, some have alignment issues, and some were off when they rolled out of the factory. Everyone has their own car and can do what they want. I am just trying to put facts out there for the original poster and keep opinions to a minimum for him. I want him to be able to make the best informed decision that he can. There are plenty of C3's out there with my tire combo and also others running 255s all around. This has been done for decades and is perfectly safe (referencing the tire manufacturer's website above). I can't count the number of Chevelles, Camaros, El Caminos I have seen with corvette ralleys and 275 tires on the rear, but that is another point all-together. People have been putting these size tires on these cars long before this forum was even around. Please don't throw out percentages because not every person that has ever owned or driven one of these cars posts up on this forum.

Pertaining to my father's car. His car was the reason I went with 255s on the front in the first place. His car was a factory original survivor (except for only two things) with only 37,000 miles and full documentation. The only things he changed on the car were the tires and he added mechanical linkage for the Tri-Power set up because he wanted to drive it every once in a while. The rest was stock. That is why he got such a big chunk of $$$ for it when he sold it. He has now owned two original c3's with 255 tires on the front. No rubbing on either of them. He is the one that told me to do it when I was shopping for tires. I have driven both of his, mine, and my uncles 71. No rubbing on any of them. This is my own actual experience with them. Others might have different personal experience.

Pertaining to my car which is a 1973 just like the OP. I put one of the 255's on the back and I have boatloads of clearance at the parking brake cable and where the rear spring is close to the tire. The 275 is a pretty close fit and I know that not everyone can run those. It was just my choice because they fit on my car, I like the looks of staggered tire setups, and I could do it so I did.