ronknop

Can anyone tell me the correct tire size for a 1965 Cutlass convertable. I have 14" rims but am not sure it has the correct tires.

nonhog

Stock size ? I can look it up in my O.M. tonight, if I can find it

Old Olds Fan

I believe stock were 7:75 X 14 Red-lines, I'm checking for myself and think a 2:15/70 X R14 should be the same outside diameter as stock, the 2:15's are 25.9" what the 7:75's were I'm working on.

jag1886

According to my factory assembly manual it could have 6.95-14, 7.35-14 or 7.75-14 depending on how it was ordered.

nsnarsk65cutlass

My 65 cutlass 2 door post has 15"x5" rims and appear to be original with the dog dish hub caps,whats the deal there i thought they were 14" til i took a look at them the other day.All 5 have the letter Z stamped next to the valve stem.

Old Olds Fan

I've a copy of the1965 Inspectors guide a good reference, what see is yes you could get 15's on the F85 but not the W29 optioned car(442) it only came with redlines and14's, Coker makes reproduction 7.75x14 redlines, as well as other side walls, they all are 27.2 O.D. I've read that you should stay within 3 percent of original O.D. I've checked again and see that Good rich T/A's 225/70R14 are 26.5 O.D. within the 3 percent, Just my input.

joe_padavano

The 3% "rule" applies to new cars where all sorts of electronic hell break loose if you change the effective final drive ratio from what the computer is expecting to see. Not really an issue for non-computer cars other than speedo calibration.

Old Olds Fan

I'm good with that, But the tire fit thing is a large problem and I see a of chat. I want to keep the stock look or at least period mags but that leaves me with my stock 14" and 0 performance tires to choose from, or coughing up $170. per wheel for 15" torq thrust and I'm still stuck with only one or two tire choices and not much meat on the ground by today's standard Is any body compiling what members are actually putting on their cars

joe_padavano

This topic comes up about once a week. The largest OD 14" tire you can reasonably find is a 225/70-14. There are taller 75-series tires, but they are tough to find. Everything else in a 14" size is somewhat smaller in diameter. How this looks is a personal choice. I don't like to see a lot of daylight between the tire and the wheel opening. I pretty much avoid 14" tires on A-body cars these days.

Old Olds Fan

Hay Joe, thanks you've answered my question, I think. I've a stock 65,442,3x2, 4spd. I need tires, so to stay at the stock diameter I need to go at least to 225/70R14, I understand that you report that it has been done, without problems.I looked around a found a post from oldsmobiledave, he's got 275/60R15's on the rear of his 65 442, they're monster, set up for drags, cool. I'm looking for the largest tire on stock rims (14") that has worked well front and rear on a 65 442 at stock ride height.
You've got to get larger tire than a 2.15/70R14 to get out of trailer tires and into any kind of performance tire, I'm looking for a 27.2 diameter to match the redlines, so how wide can we go in a 70series with out problem, I'm probably good with 225/70's but bigger is better?

Old Olds Fan

Bigger also seems to bring a larger selection of performance choices, I'm a fan of road racing and I like a big foot print so, to the point how big is to big, when do PROBLEMS show up size wise.

Old Olds Fan

Finished checking 2.225/70R14 is it. stock wheel is 14x6" anything bigger really needs a wider wheel, Thanks again Joe

HonestDave

I run into this frequintly with my old cars. You're about right on for 225 being the max for a 6 inch rim. I just sold my 14 x 7s with 235/60s because I couldn't fit them over the front disc callipers. Switched to 215/70/15 on 15 x 7 Olds rally wheels. Won't know how they look until I get the car out from the storage spot. Had to lay on the ground to stuff them on. If they look too weeny, I'll put on a set of American Racing Wheels I've got with 245/60/15 and 225/60/15 and just run with them.
Or maybe transfer the tires to the rally wheels.
Indecision is driving me crazy !!

joe_padavano

The 215/70-15s are taller than either your 225/60 or 245/60 choices. They are also 1.5" taller than the 235/60-14s, which would have been waaay too small in my opinion. By the way, factory disc brakes came with 14" wheels. Your problem is that your original wheels have the drum brake-only profile on the backside. Later 14" wheels do clear the disks.

HonestDave

Actually, I'd heard that about the newer wheels. I kind of wanted to stick with the original sixties style rectangular holes and bolt-on center caps. Didn't work, of course, so I sold them to a fellow who just brought down a 68 442 he purchased in the Okanagan.

joe_padavano

Are you talking about SSII/III wheels? ALL factory SSII/III wheels in ALL factory-available sizes (14x6, 14x7, and 15x7) clear factory 10.75" front disk brakes. I had bolt-on center 14x6 SSII wheels on my 68 442 back in the 1970s and 14x7s came on my 70 W-30 with disk brakes from the factory. Also, all SSII/III wheels have the same cutouts. It's the chrome trim piece that's different. It's just a snap-in piece.

HonestDave

I'm not sure of the SS series. I know they were removed from one of the kid's cars, a 69 Cutlass, and they had bolt-on center caps.
I also know someone added front disc brakes to my 65 442, I have the bill for $1800. The 14 x 7 rallys don't fit on the front, they rub on the callipers and sit lop-sided. What can I say? I would have kept them if they had fit.

joe_padavano

If the disks were aftermarket, all bets are off. If they are identical to the factory brakes, then all SSII/III wheels ever made will clear.