What Tire Size for my '52 Cambridge?

[JerseyHarold]

I want to replace the tires on my Cambridge...the original size 6.70X15's from the 1960's are on there now. I'm thinking P205/75-15 or 215's should work. What are you guys (and girls..don't wanna be sexist here) running on your cars? Then there is the oval valve stem issue. I know screw-in oval valves are available, but has anyone found rubber snap-in valves that work? I'm trying to stay with 'main-stream' suppliers rather than the 'antique vendors' because it usually works out less expensive that way. Any thoughts appreciated.

Harold

[greg g]

wouldn;t go smaller than 215 75 15's. There was a rather long recent thread all about radial tire sizes. About 2 weeks back.

[55 Fargo]

Hi Harold, a 6.70 15, is 27.4 inchs in diameter closes matches are a P205 75 15, 27 .3 inches, but what is your rear diff ratio, if you are geared low and are running with a 3spd trans, possibly as Greg has mantioned, then may be a P215 75 15, 27.8 inches in diameter, might be a better bet. But if your speedo is dead on now, going with a taller tire will alter that accuracy, also check your rim width, to determine what size of tire you can go up to.............Fred

[Jeff Ivan]

Harold, on my 1951 Cranbrook I am running size 215/75/15 radials. I am still not sure of the rear end ratio on my car, but the speedometer seems to be right on. I checked the speedometer just today. The local Police Dept. has a trailer with a screen that lights up with your speed as you drive past, they had it parked on the main road near where I live and I drove past it three different times today. I think you will really like the difference in the ride if you go with radial tires, just barely notice it is only very slightly harder to steer when parallel parking. Also, the threaded valve stems are easily available at any local tire shop that sells larger truck or tractor/ equipment tires. My tires are cheapies bought new by the previous owner but never mounted, and given to me as part of the purchase deal. When I took the wheels to get them mounted, they got the new valve stems from the tool box on their mobile service truck. Make sure the bead edge on your wheels is NOT badly rusted/pitted /damaged or weakened and you should be OK.

[Ken Bartz]

I am also running 215/75/15 tires on my Cambridge. The tire store did not know how to deal with the oval valve stem hole so they gave me a deal on a set of radial inner tubes. This worked out well for many miles until we made a long trip on a club event. I awoke in the morning at the motel an noticed I had two flat tires, left front and right rear. Well, I thought someone in the club must be playing a practical joke on me. I found a 12 Volt type compressor and pumped them up. We went on the days activities, then later in the afternoon the same two tires were low on air again. Then I was concerned. I mounted my spare and borrowed a spare from another guy. After I got back home I went back to the tire store to find out the problem. The tire manufacturer saw it necessary to put a small 1/2" X 3/8" stick on label on the inside of the tire. The radial tire flexes enough where the inner tube had a hole worn it where this sticker is located. Go figure. Now I know that there are bolt-on valve stems. As a side note, along the same tire business. I just bought a set of tires for my modern car (different retailer). I found a similar label stuck on the bead area of these new tires. He installed one of the tires on a rim and checked for leaks. Sure enough, there was a very slight leak where the label is located. Most certain to cause problems a few miles down the road. The labels were removed from all of the tires and I was on my way.

[JerseyHarold]

Thanks everyone for your replies. It looks like I'll go with the 215's. I'd like to use rubber snap-in oval tire valves, but I guess I'm stuck with the bolt-ins.

Ken, that was a very interesting insight concerning the tire labels causing grief. Something to watch for on any car....good of you to share.

Harold

[daddyo23]

I'm running 215's on my '51 Cranbrook, also. You can get the wide, short rubber valve stems at any Napa or other part shop. Ag dealers have them, too. They fit fine in my stock rims. I put 1400 miles on them this summer with no leakage.

Wayne P.

[Normspeed]

It looks like my 53 had round holes in the factory rims, I can see it where the spare tire tube valve stem is. My other 4 have the screw in type. I like them, they're tough.

[BobT-47P15]

I have seen those metal screw-on valves on several old cars purchased back in the 1970s. They were used pretty regularly back then.

I had a set of 205-15 radials on my 47 Plymouth for a while, but felt they looked a little small. Think 215s would have been better. But already had those tires for free. Now using 6.70 x 15 bias ply on the car.

[oldmopar]

Just looked at mt 52 cambridge it has 215x75 R15's 3 wheels have the valves stems look like the short round ones described above one has a tube in the tire hole looks to be round