(first posted 1/6/2012) Growing up is an endless series of awakenings, as the veil of innocence tears bit by bit. In the fall of 1964, when the all-new ’65 Chevrolets came out, I went down to the dealer’s unveiling party, and partook of the cookies and GM Kool-Aid. Beautiful bulging hips and sweeping roof lines; Yes! And big wheel wells to go along with those new wider fenders; Yes! And the usual orgy of Chevy power, all the way up to 400 hp; Yes! Eleven years old, I was oblivious as to what was actually hiding inside those shaded wheel wells on the overhead-lit showroom floor.
Fast-forward just nine months, and I’ve been dropped off at the Mennonite farm for my annual tractor driving vacation. The Yoders have a new car, a 1965 Bel Air four door six sedan, just like this one. But now that I’m really looking at it in the bright Iowa summer sun, something suddenly seems out of kilter: the tires look oddly puny, lost deep in their big wheel wells. I walk up to one, bend down, and read the tire size: 7.35 x 14. That’s smaller than the tires on our new mid-sized ’65 Dodge Coronet! GM’s record $1.7 billion ($12 billion adjusted) profit in 1965 was riding on the back of dangerously undersized tires.
I wouldn’t be surprised if the ’65 Bel Air in the picture was riding on something a bit bigger than the standard 7.35 x 14 mini-donuts. Just to put that size into modern context, that equates to a P185/80R14 tire, on vehicles that weighed some 4,000 lbs empty, and readily topped 5,500 lbs with six adults and luggage. Modern radial tires that size might be rated at 1300 – 1400 lbs capacity each. A two-ply bias-ply el-cheapo UniRoyal in 1965? Not that anyone really knew what their tires’ or car’s total rated capacity was anyway.
OK, I realize that the pendulum has swung the other way, and today’s new cars run on ride on ridiculously huge tires and wheels. But that’s not the point. As the above specs point out, at least the wagons and convertibles were bestowed something a bit less skimpy.
I’m currently re-reading “On A Clear Day You Can See GM”, the book that John Z. DeLorean dictated to Patrick White. He repeatedly comes back to issues like undersized tires that saved GM maybe $3 per car, and other such nickel and dime exercises. Some of which, like the missing $3 front anti-sway bar or $15 rear camber-compensating spring on the Corvair, undoubtedly killed unsuspecting folks; one of GM’s genuinely deadly sins.
But how many folks were killed because their overloaded ’65 Bel Air heading off to vacation lost control because of those puny tires? Hello Firestone-Explorer debacle! But this was thirty years earlier, when (almost) no one thought twice about why that Bel Air was lying on its roof in the ditch.
GM took a momentous shift when Frederic Donner became Chairman in 1958. For the first time since GM’s management structure was laid down by Alfred Sloan, true executive control fell in the hands of a bean counter. Up to that point, GM’s President was the functional top executive officer, but by the time Ed Cole took that job, its powers had been clipped by Donner. And going forward, power increasingly vested in the Chairman and the newly-minted position of Vice-Chairman, both financial officers.
Of course it took some time for the effects of GM’s top management switching from operational executives to financial executives to be felt. In the short term, the benefits that were accrued from expanding GM’s operations in the late fifties by President Harlow Curtice was reaped by Donner and his hand-picked President, Jack Gordon. But the lack of true automobile builders and marketers at the top eventually caused the mortal drift that GM soon found itself in.
The undersized tires were not an issue exclusive to GM, although big Fords were riding on 15″ tires, but still too small in width. And Plymouth was only marginally more generous with the rubber. But GM was the industry leader, and the others had little choice. If Chevrolet had suddenly announced that fat 15″ tires were now standard, and extolled their enormous benefits in terms of ride, handling and safety, the rest of the industry would have had to follow.
That’s exactly what happened anyway, in just a few short years. The not so subtle pressures from the government as a result of Ralph Nader’s efforts and the growing awareness of the legal profession regarding product liability, in the form of raised expectations of safety and performance, all conspired to force long-overdue changes on GM’s products
By 1970, the fundamentally similar Bel Air was riding on substantially bigger rubber: F78x15 or G78x15, which correspond to 205/75R15 and 225/75R15 in today’s sizes. Now that’s more like it. Looks so much better too. Too bad it took another year for disc brakes to become standard across the board.
GM’s profits for 1970 were down some from 1965. The bigger tires? Undoubtedly! (not really, of course) But GM bean counters soon found other ways to cut costs.
Wasn’t Mercedes-Benz a proponent of small wheel/tire combinations in the 60’s? Their reason (excuse?) was less unsprung weight for better ride and handling. Of course GM did it to save money, it larger wheels would have been cheaper they would have been on that Biscayne, no question.
Interestingly, the standard tire size on a mid-60s 250S or 250SE was also 7.35-14. The Mercedes was lighter than a full-size Chevrolet, of course, but not by as much as you might think — the difference was something like 300 lb, although of course it depends how the cars were actually equipped.
Well, you’re right, inasmuch as a Bel Air six sedan with zero options did weigh about 300 some lbs more. But an Impala V8 four door weighed another 300 lbs more, and that’s before adding the typical Powerglide, power steering and power brakes. That probably added another couple of hundred lbs. never mind the possible AC or other goodies. It was very easy to get up to 4000 lbs. And then there’s the fact that the Chevy was nominally a six-seater.
Did Chevy require larger tires with the 327 or 409 engines? Maybe; maybe not.
Another issue I didn’t properly address here, and should have, is that it’s not only a matter of size alone, but also tire quality.. In an effort to reduce tire cost, the Big Three along with the OEM suppliers had developed two-ply bias-ply tires recently that were generally considered to be inferior in weight and heat capacities than four-ply tires. This was a controversial issue at the time, and many folks would replace their two-ply tires with four plies.
And even among four-ply tires, there were of course big discrepancies between different tires. There were always tires available that were designed to have greater speed and weight capacity. But one had to order them optionally.
There’s no doubt in my mind that the tires used on the Mercedes were four-ply European tires fully capable of handling the car’s top speed and its specified weight capacity. the German TUV was a real stickler about things like that.
I used to change tires at a gas station back then. The OEM two-plies felt decidedly lighter and feebler than a higher quality tire. It’s subjective, but they felt junky.
There was a wide range in tire quality back then, and the pricing reflected that. The OEM tires were about one notch up from the truly crappy el-cheapos that some tire shops sold.
Don’t get me started on the bias-2 ply tires, They were probably the worst tire foisted upon the unsuspecting consumer. I can remember driving cars with them and the best way to describe them as you were driving down a normal road the car seemed to kick up one of it’s legs like a horse. Also going over steel grated bridges the whole car would dart back and forth even though you never even moved the steering wheel. And the nylon cord versions would flat spot badly in cold weather which makes it seem you were driving on square tires. Together with the number of blowouts(haven’t had one in almost 40 years, before that I had at least one every other year for my first 10 years of driving), the low, low tire life in miles in comparison to today’s tires and the better handling of every pre 1975 car that I have had radial tires installed on in no way make me wish for the tires of the “good old days”.
That’s why I noted that the weight depended on how the car was equipped — there was a spread of 500+ lb between a strippo six-cylinder Biscayne with three-on-the-tree and a Caprice with 396, air conditioning, and all the trimmings.
As best I can determine — the brochures are vague on this point — the 7.35-14 tire size was only standard for six-cylinder B-body Chevrolets. In 1963–64, V-8 cars got 7.50-14 with the Turbo-Fire (283 or 327) engines or 8.00-14 with the 409. Starting in 1965, cars with the 283 or 327 got 7.75-14 tires as standard. The 409 included 8.25-14s — and wider wheels — like the wagons; I believe some but not all cars with the 396 (added mid-year to replace the 409) did as well.
This of course doesn’t change the basic point, which is that a 7.75-14 two-ply (four-ply “rated”) tire is still on the marginal side for cars this size. With a decent four-ply tire and proper tire pressures, it might be adequate for a lightly optioned sedan, but I’d still get nervous about high speeds on a hot summer day with a load of kids and luggage.
I assume Mercedes specified actual four-ply rather than four-ply rated tires, and while they had the same tire size as six-cylinder big Chevrolets, the Benz had 6-inch wheels whereas Chevrolets got 5.0×14 wheels with either the 7.35 or 7.75 tires. Still, I was surprised the tires weren’t a little bigger and the W108 was heavier than I’d remembered offhand.
Funny, just today I was doing some hypothetical research on the Kia Forte ‘Koupe’, which I kind of like, and was pondering as a good entry-level semi-sporty 2door, of which there are so few any more (Honda Civic coupes starting well over $20k, for instance?!?!?). Tire sizes for the Kia: base-16″, uplevel model-18″.
IIRC, the 85 Chrysler Conquest that I still lament letting go of back in ’89 was rolling on 15’s. What is going on? An 18″ tire on a lightweight 4 cylinder sport coupe? Really? I had a Rip Van Winkle moment reading those specs. When do this happen?
Bigger brakes happened. And the Conquest brochure I’m looking at says it came with 16s.
Opting for 18- or 19-inch wheels doesn’t generally include bigger brakes, though.
The brakes are generally designed for the size of the car. My CTS has 19 inch wheels (an option) but the tires are wider with a lower profile. Since the car is AWD, the tires are all season. Not sure that there is a difference in handling.
I had a 63 fairlane 500 2 door 221 v8 2 speed auto that must have weighed 1000
more than a falcon guess what it had falcon 13 in wheels and tires no wonder I couldn’t
keep tires on it and mopar did the same thing with the dart!
The first thing I did when I bought both my ’67 Dart and my later ’69 Valiant was to change them over to 14″ wheels and tires, It was a little more difficult and expensive to find and buy the small bolt pattern Mopar 14″ wheels, it was worth it. The ’69 Valiant was the second car I put radial tires on. Bought a set of 4 used radial tires 235R-14(import truck tires)with maybe 1\2 to 2\3rds tread for $40.00, drove them for another 40,000 and when I sold the car(wish I had never done)they still had tread showing,
One of the few changes made to the Valiant for the Aussie/NZ market was 14 inch diameter rims of course they still came with skinny cross ply tyres but the diameter increased.
those central hardware tires were PHARIS tires dad had one blew out on his 62 Galaxie
on the highway,on vacation a lot of dads tires came from Western Auto in St Ann
somehow ,dad got to work at the plant every time with his DAVIS snow tires
Couple of disconnected remarks on tires….
I scrounged around and found a set of new Michelin radials for my near-new 1965 Barracuda. They were funny-looking, dark brown instead of black, and they howled on the highway, but their effect on the car’s handling sold me on radial tires.
On the cheap variety of tires, I bought a 1960 Chevy pickup that had a set of them. By the time I’d driven it a couple of thousand miles I’d had two flats. Those tires were all were replaced after the third one was punctured by the head of a screw.
Cop cars in the 1960’s and 1970’s generally had tires quite a bit larger than civilian vehicles. Lots of us remember the Aspen and Diplomat cop cars with those great big blackwalls that almost stuck right out of the wheel cutouts. My 1976 Dart ex-cop car had 14×6-inch wheels – I don’t remember the tire size now but they almost were too big for the wheel cutouts too. Needless to say with those tires, the heavy springs and bigger-than-stock front sway bar and a rear sway bar, the car handled just a tad better than civilian A-body cars, which could be had with A78-13 tires.
Most cars of the period offered bigger tires and all sorts of interesting stuff in the back pages of the options list, including various heavy-duty pieces. I assume that in most cases, there was one set of heavy-duty stuff (brakes, cooling, suspension, transmission, etc.) that was either sold piecemeal or in different combinations for different civilian and fleet buyers. For instance, it looks like you could get tires up to 8.55-14 six-ply on mid-sixties big Chevrolets for heavy trailer-towing duty.
Of course, the trick was always that to get even most of the regular-production options, you had to know that they were available and find a dealer who was both knowledgeable enough and willing to let you put in a weird special order rather than looking at you baffled or trying to get you to buy something already in the showroom.
Exactly – American cars could be optioned in a way not available today. If you invested the time you could, for example create something which would go around corners and stop as well as any European sports sedan, and from what I know about Austrian-spec American cars, the local dealers made certain they had the “right” options. That’s why (if you’re an originality freak) original imports are worth more here. Nowadays the aftermarket industry has anything to make a 60s American car (well, at least the popular models) handle and brake like a modern car, but that’s another matter…
The good news is that with most modern cars, you don’t have to resort to the options list to get adequate tires, brakes, and cooling capacity. There are things that are regrettable about the demise of the à la carte ordering system, but that’s not one of them.
I agree about the premise in general, but lament not being to determine what I want and what I do not want in my car anymore.
At Cadillac you can get upwards of 4 trim levels: base, luxury, performance and premium. The performance trim is more for the sport models, and allows one to get everything that you can get with the premium trim (but at a higher price). The premium trim level has the most standard equipment with few options. Some models go beyond this with a platinum trim level. The luxury level offers some luxury options not available on the base level.
Something no one has addressed is rim width. I had a 62 olds f85 with 13 inch rims with, if remember correctly, a 4 1/2 inch width. only so much tire can be stuffed onto a narrow rim before it begins to create more problems. I had to find rims from another vehicle that not only had a larger diameter and width, but also a 4 lug pattern and correct offset. I believe they came off a Mercedes but can’t remember for sure. Aftermarket rims were not readily available for all cars back then.
Corvair rims were 5 1/2 x 13. Cheap way to upgrade a Datsun 510 from stock 4″ x 13
A disadvantage of wider tires is they require more
Caster or SAI angle to roll in a straight line. And,
they suck on snow or ice.
Narrower tires/wheels focus more weight in a
smaller area, and that weight returns the steering
tires(and steering wheel) to center much quicker.
What would have worked back then – and today –
would be to go from P205-75-R15 to something
like P205-50-R18. Same width(205mm) and height,
but lower sidewalls for less flex, and enough blingy
rim(18″!) for most folks then and now. Plus: a ratio
like that would not need as much caster angle or over
boosted power steering.
The 1965 Impala (283) weight was about 3700 lbs (class car database). A search for bias ply tires results in a 735×14 with a load rating of 1350 lbs@32 psi. How tires were then compared to now is not clear, but the tire industry is not spending much on bias ply tires as far as I know (except for trailers).
The base tires were probably good for a total car weight around 5500 lbs.
The 1965 Chevrolet brochures are unclear about tires. The 1966 brochure states that one should see your dealer about tire sizes. My 1967 price guide says 8.25 wsw (probably 14’s) are a $36 extra. My guess is that an 8.25 tire will have a load capacity of 1900 lbs per tire or about 7500 lbs for the car.
As I mentioned above, the standard tire size for small block V-8 Impalas in 1965 was 7.75-14 — the 7.35-14 was for sixes. The 3,700 lb figure sounds about right for an Impala sedan or hardtop with a Turbo-Fire engine and a few typical options, but the 1,350 lb load figure seems high for two-ply tires of that vintage; I’d have to dig into it some more. (I think there was some variation depending on whether you had two-ply, four-ply, or six-ply tires and between different brands.)
I don’t see much information in 1965 road tests on the tires. I think that the 2 ply tires had a 4 ply rating (compared to what? cotton tires?). But moving forward in time, car and driver notes that a D70-14 tire on the Camaro is rated at 1120 Lbs@24 psi. This is a 6.2 inch wide tread?.
A 1967 Corvette test has 7.75-15 tires rated @1270 lbs@24psi. These were 2 ply. A 67 Mustang with F70-14’s is rated at 1280lbs@24psi
I don’t know if the load capacity would increase at higher pressure (probably not). What I reported above was for current bias ply tires that are available.
F size tires are 7.75’s. My feeling is that Chevrolet did not put tires on that were dangerously small. The tires may have worn out fast, but really the buyer/owner of the car should have used some common sense when is came to replacing the original tires. Dealers probably were happy to replace black walls with white walls at a price and could then upgrade.
The 1965 Car Life road test, which includes an in-depth technical discussion of the new platform, talks about the tires. (Their data panel shows a tire load rating of about 4,800 lb, although that’s listed as being for the 8.25-14s, which weren’t standard on the 327-equipped car they tested; I have a feeling the data panel is in error, but I’m not sure which part.)
Typically, tire load ratings specify a particular tire pressure (36 psi seems to be pretty common, although it varies), which I think is usually the maximum recommended pressure. The fine print of the owner’s manual for many cars, particularly in those days, often listed several different pressures — one for normal driving, one for high speeds and/or heavy loads. Both of those values would often be below the rated maximum pressure; you might see 24–26 psi for normal driving and 32 psi for high speeds, for instance. The load capacity is likely to be lower at pressures below the rated maximum pressure (or above it — overinflation has problems of its own).
D70 would mean a tread width of a little over 7 inches (roughly 180mm), not 6.2.
When I first started driving in the mid 60’s my father kept the tire pressure at 32-34 lbs in his tires. He was an advocate of installing the best tires(4 ply actual)and larger sizes(7.75-8.25), quality shocks(Monroe HD shocks front and Load Levelers rear), and the best quality and largest size riveted brake linings available. I still carry his mantra to this day translated into today’s items.
In the 60’s there was a lot of change in tires which had been rather static for the last 25 years. New materials, aspect ratio’s, construction, size designations, tread designs and other changes meant the tire industry was going through an era of rapid change. The size was just another item although I believe most of the cars OEM tires were seriously compromised in size, materials and construction.
As one of the posters above mentioned about people getting new tires for their cars when they were new or nearly new. As he also posted every tire store had racks of these tires described as “take offs”. There were also private party ads in the papers selling almost new tires that were described as “take offs”. Everybody in the day knew what that meant.
Nowadays, vehicle owners, and mechanics – who
by the way should know better! – simply put in what
it says on the TIRE. That Max cold pressure is
just a safety label, not what may be the best for
one’s particular vehicle handling & comfort.
Consequently, they are not getting the most out
of their vehicle’s performance, or out of modern
tires with decades of advancement in them since
the good ol’ days described in this article.
There’s a load information and pressure decal
on the B-pillar of most cars today for a reason.
Even if you add a couple PSI to the vehicle
mfg’s recommended pressures, it’s still wayyy
better than driving around on four basketballs.
My owners manual say to set the cold inflation pressure at 41 psi for cruise at or above 100 MPH. Normal pressure is 32 front, 36 back.
I was finally able to dig up something I’ve been trying to find forever on the GM Heritage Center site…
https://www.gmheritagecenter.com/gm-heritage-archive/vehicle-information-kits.html
Just picked one at random, but this seems pretty typical… the amount of information there is overwhelming.
1964 Impala Sport Coupe
283 V8, Powerglide, power steering, power brakes, A/C, AM radio
Standard Tires+Wheels: 7.00-14-4PR (2-ply rayon) BSW, 14×5 steel
Tire Capacity: 3,900lbs. (975lbs. x 4 @ 24psi recommended)
Curb Weight: 3,747lbs.
For example: My daily Kia door decal
states 30PSI front/rear for the one tire
size listed on it, and 60 on the donut in
the trunk.
I keep the tires at 32-33psi, and feel that
this is the sweet spot *for this car*.
After a routine service appt, I always find
the tires inflated to their max, or close to
it – 40 to 41psi. No WONDER the car feels
so hair-trigger when I drive from the dealer!
I’ve told the service dept not to do that, but
it’s hard to get the message across if a
different tech works on it every 5-7,000
miles.
Sean: I looked at the 1965 Chevy’s and found that the curb weight of the Impala SS was 3750 lbs. The base tires are 7.35×14 but:
the 327 V8 got 7.75 tires and the 396 got 8.25. The load for the base tires is 1020 lbs, then 1100, and 1180 for the others.
One point is that overloading the tires will wear them out faster, but the tires won’t explode just because they are overloaded. I think that GM was putting minimal tires on Chevys, and people should have upgraded if they were overloading the cars.
One thing I do remember is that tire manufacturers offered more than basic tires. You could get better tires.
@SomeOneInTheWildWest – For sure. Exceeding the ratings once, or even many times, doesn’t mean fire and brimstone will rain down from the sky. Like you said, the only consequence most people probably experienced was tires that wore quickly. But, the fact that there was such a narrow margin at all speaks to exactly what Paul is discussing in this article. In the ’64 Impala example I gave, there’s only a 153lbs. difference between curb weight and rated capacity. Having to pull an emergency maneuver on the highway with some wear on those tires, improper inflation, a heavy load or combination of all three would become very dangerous.
Sean: I also discovered that increasing the tire pressure to the maximum recommended cold inflation pressure will increase the load capacity. I think 32 psi is about the max, and increasing the pressure 8 psi will increase the load capacity by about 240 lbs per tire, from 1020 to 1250+.
May ’66 story about the 2-ply tires (bonus sidebar has comments by Hank/Deuce about car safety and Detroit):
The Deuce can get away with saying that since he has the moral high ground in this case, AFAS Detroit is concerned. His cars a primitive safety package as an option in ’56 that did include seat belts.
I know Cadillacs were equipped with 15″ wheels through the 1950s and ’60s. My ’62 convertible was factory equipped with 8.20×15″ tires. For what it’s worth, it also has a standard padded dash, first year dual circuit master cylinder, and the accessory seatbelts. So, at least Cadillac money got you some better rollers and a bit more safety in your GM car.
How GM of GM. What good is performance if its tires aren’t up to the task of holding the car on the road?
If I remember correctly, Ford dropped from 15″ to 14″ rims when it did its downsizing in 1979 for the LTD. Do they have any issues??
It’s not in my nature to defend Ford, but dropping tire size at the same time that you’re doing everything you can to reduce mass isn’t the same thing as dropping tire size to save money while the car is still expanding with each new model.
I remember that at the end of the 60’s, bias ply tires were the standard for domestic cars. I think Michelin tires were available at some point, certainly by 1970. The used Buick Riviera I bought had Michelins on it. Domestic tire companies started to sell radials in the 70’s, but I am not sure when.
Don’t know when they might have become optional (or even generally available) in the US market, but I think the 1969 Lincoln Continental Mk III was the first domestic vehicle to come with radial tires as standard equipment.
Ford was an early adopter of radial tires. It wasn’t long after that ’69 Mark III that they trickled down the line. Our ’72 Comet 4dr-LDO also had them, big meaty (for the time) ER70-14 B.F. Goodrich Radial Steel RS.
Optional on the ’69 Skylark/ Special Deluxe, not sure about the GS, or the senior Buicks that year.
They were optional on the first-generation Pontiac Firebird, I think in ’67.
I just scoured all my ’67-’69 Firebird sales literature and found nothing on radials, lots of references to wide-ovals, though.
My buddies mid to late 60’s larger sized AMC’s also suffered from small tires, no front sway bar and drum brakes all around with resulting poor handling, braking and a very unrefined ride. But like the Chevy in this article were bare bones base models and were made for the really frugal old timer. Should cars like these ever have existed? Not in my opinion today. But the world was a very very different place in that time era but those bean counters were alive and well even then as this article so correctly states.
Looking through the GM Heritage site, I found that increasing the cold inflation pressure increases the tires load capacity by about 30 lbs for each 1 psi of increase. So, going from 24 psi to 32 would increase the tires load capacity by more than 200 lbs. Thus the base tires could have a load capacity of 1250 lbs @32 psi, instead of 1020 lbs @24 psi.
Of course this requires the owner/driver of the car to be competent, which is most unlikely. If the owners manual says something, possibly people will know.
Couldn’t exactly do that on a pre-64 Corvair,
could we? GM already knew the consequences
of not inflating those Corvairs to that specified
front/rear bias.
my first car – an 84 Austin Metro – had 165s on it which I thought were pretty mean.
what were the tyres on 2cvs? I seem to recall 135s being about right?
mean as in excellent dude (just to clarify)
Looking at older Chevrolet (and Ford) owners manuals I find that both suggest for heavy loads or long distance higher speed driving that tires should be inflated to higher pressures. Owners should have been aware that increasing the tire pressure was a good thing. The problem is how much information was really available about tires to the typical owner. I do not remember much from that time period. My first car was a 1969 and I do not recall any details about tires for it except that they were bias ply.
The 735×14’s that were standard for the Chevrolets in 1965 had a load rating of 1020 lbs @24 psi (see GM heritage). If you google tire pressure vs load ratings for modern tires you see that increasing the pressure to 32 psi will increase the load capacity by 250 lbs per tire or more. So dangerously undersized? I don’t think so. However, was there enough information provided in the owners manual to make people aware of what to do about overloading their cars? I am fairly sure that maximum cold inflation pressure for bias ply tires was 32 psi.
This article is really flawed.
In today’s world we are being conditioned to have OVERSIZED rubber because of looks, not because of any inherent goodness of performance. There is simply no need for 16’s or above on modern vehicles other than to give an appearance.
I have been lucky to work in various parts of the industry and can tell you that the 50’s were trending to smaller tires for precisely the same reasons we are thinking “size matters”. As cars were becoming lower in styling, there was more of a design requirement to have smaller tires to bring the cars down; think of how tall the cars were starting in the 1950’s. By the end of the decade there was no point to putting 16’s on even a big car because the tires weren’t that capable to begin with. We are talking bias ply tires and width of the footprint was not that important unless you were driving a performance car. Quite simply, the suspensions were trending to soft and loose, so you didn’t need adhesion of the tire because the suspension couldn’t handle that to begin with.
A lot of what is said here is often our reality and standards being placed on old vehicles and wondering why things were done as they were. The 50’s and 60’s trended away from larger tires of the 40’s and 30’s – even making slightly wider footprints. The bias ply tires were garbage even up to the performance levels compared to steel belted radials.
I have to laugh at the notion that small cars need 16 inch tires – but we also have to factor in that the sidewalls on biased plys were very tall – so what stands for a height of a 16 inch tire and wheel package could equal what was a 15 inch tire and wheel package solely on height of the inflated product.
You obviously missed the whole point of the article. it’s not about the rim diameter, although that’s part of the equation. It’s mostly about tire size, other than rim diameter. And also about two ply tires, that came with a load rating that was very easily exceeded.
The shortcomings of these undersized tires were commonly known, decried by publications, and were known to be a safety risk.
The fact that GM substantially increased tire and wheel sizes on their cars from 1965 on, the year Ralph Nader’s book “Unsafe At Any Speed” came out, makes it very clear what was going on. The threat of regulation and lawsuits was what it took to get appropriate sized wheels and tires on cars starting in about 1970 or so, and radial tires a few years later.
This has nothing to do with the trend to ever larger rim diameters in recent years.
I have to laugh at the notion that you don’t realize that load ratings on tires are essential for safety, and that those ratings are not directly related to rim diameter. You’ve missed the whole point of the article.
Agreed! The wagon wheels trend is ridiculous. And wider
wheel/tire combinations need greater caster angle to go
straight at speed.
I would, on the other hand, like to take an
existing ’64 Impala stock tire package, and
replace the rim with one of same width, but
greater diameter, i.e. 16″ instead of 14″.
The tire would be the same diameter and
width, but would have lower sidewall profile
to accommodate the greater diameter
rim.
So you would have a tire/wheel combo the
same overall dimensions as in ’64, but the
rim would take up more of the space between
the hub and the wheel. This actually doesn’t
exist, but I would love to see how such an
animal performed in real world conditions.
Instead, both wheels and tires have gotten
bigger in BOTH directions, which I don’t feel
is of any substantial benefit to ride or handling.
Whoever is responsible for ad placement appears to have seen to it that when I look at this post in 2021 on my Android phone, all the pop-up ads are for GENERAL MOTORS!
This is probably my favorite post in the history of CC
John DeLorean’s book had the chapter describing these decisions as Why Do Moral Men Make Immoral decisions. He in turn fell into the same trap. So it goes.
The original stock small tires on my ’74 Dart Sport (6.95×13 as I was reminded by Daniel Stern), were replaced at the first chance I got with F78-14s if I recall correctly. Those small donuts contributed to a loss of control at speed on the highway on one occasion, or dry pavement. That car fishtailed back and forth on me, when I finally brought it to a halt I was sideways in a live lane or two. Thankfully there was no damage or injury.
If I count correctly this is the 275th comment on this excellent piece. Masterful writing by Paul, our esteemed author once again.
Indeed. I am wondering if this post has the highest comment count ever!
6.95 × 14s on the ’74.
I often questioned why so many full-size cars in the 60’s came with 14-inch wheels/tires. This post enlightened a lot of that. All the Chrysler products and one Ford that I owned from the 50’s- 60’s had 14’s. They all seemed to have gone to 15’s by ’69 or ’70?
If I’m recalling correctly, the old inch numeric passenger car tires were 82 series tires. IE. 7.75×14. The alpha-numeric sizing went to 78 series as the standard. IE. G78-14 including radials. Of course, the early muscle/sport cars went to 70 series tires. Imports were often 80 series in 12, 13 or 14-inch tires.
I have no problem with larger rim/wheel diameters – up to a point.
My issue is with the ever-widening of stock tires, especially since the late 1990s.
Cars move forward and backward, not sideways, so I don’t understand the need for tires approaching one foot wide! Low profile, to me, is any tire with an aspect of ’60’ or lower in the middle of its size designation, IE “P215-60R16”. That’s as ‘low’ as I’d go, if I could choose the size of tires on my next car.
And the “looks” argument is completely lost on this old has-been: I do not approve of changing any part of the car which comes in direct contact with the roads for cosmetic reasons. There’s just too much at stake there, and besides, the manufacturer who designed the vehicle knows what size wheels & tires work best with it, so why play ‘driveway engineer’ with your safety?
Maybe the small tire-wheel assemblies on the regular retail cars during that decade was one reason why some sleeper builders sought out the wheels and tires from the various police and highway patrol interceptor versions of the cars sold by the automobile manufacturers. I knew a guy who bought up the various pieces/parts from suppliers so he could upgrade his station wagon with the same wheel-tire assemblies, engine upgrades, transmission upgrades, suspension upgrades, braking system upgrades, and electrical system upgrades that the Illinois State Highway Patrol cars had from the factory. A sort of mild hot rodding in a plain paint wrapper.