1970 Tire Size
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Those are the only two regular retail choices you have for raised white letter tires that sorta look period correct. Nitto has RWL but they're HUGE letters.*
Be aware that there are also only 2 size choices to keep the speedo reading correct: 215-70r15 (most closely matching original F70x15) and 235-65r15. These diameters ( 26.9" and 27") most closely match the original tire which is what the speedo gear is showing. I went with 225-70r15 for the BFGs on my '72 a couple weeks ago (27.4" diameter) which causes the speedo to read slower than actual. It's no concern around town because the error is only a mile or two/hour but at highway speeds it's close to 5mph off. I use a phone app to monitor speeds for both of my Corvettes rather than the speedo.
Here's a decent size comparison calculator, though, I don't think their speedo is accurate to my experience. https://tiresize.com/comparison/
*Corrected further down thread:
Be aware that there are also only 2 size choices to keep the speedo reading correct: 215-70r15 (most closely matching original F70x15) and 235-65r15. These diameters ( 26.9" and 27") most closely match the original tire which is what the speedo gear is showing. I went with 225-70r15 for the BFGs on my '72 a couple weeks ago (27.4" diameter) which causes the speedo to read slower than actual. It's no concern around town because the error is only a mile or two/hour but at highway speeds it's close to 5mph off. I use a phone app to monitor speeds for both of my Corvettes rather than the speedo.
Here's a decent size comparison calculator, though, I don't think their speedo is accurate to my experience. https://tiresize.com/comparison/
*Corrected further down thread:
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From: Crossville TN
245's will fit on about 1/2 of the early C3 cars. It all has to do with how well everything on the steering is positioned. ALL 235's will fit (unless the car has been damaged). In 1975, the wheel openings were enlarged to allow wider tires.
