Wire Wheels and Radial Tires, what R U Drivin?

[JohnD1956]

Please help me figure out if I should equip my new Wheel Vintique Skylark rims with Radials or Bias ply tires. Reading the posts under the recent Wire Wheels titled thread, it appears there are at least two people who have experienced problems with the remakes of the Kelsey Hayes 40 spoke Skylark wheels, when using Radials. I called Wheel Vintiques and they claimed no knowledge of this type of problem, yet it appears that they were advised of the problem on one of these cars right after the Centenial. I can't figure out why they would not give me the straight scoop?

There were a lot of cars at the meet with these wheels. Please tell me what you're using. I would rather have radials, but if I have to use bias ply tires, then so be it. I would like to avoid buying radials just to find I can't use them on anything.

Please advise what your experience has been ( if any) with Radials on these rims. Thanks for all your help.

jld1972@empireone.net

John d

[NTX5467]

You might check with Coker Tire or someone that can sell you a tire/wheel package as a turn-key deal delivered to your door step. If they'll sell you such a package deal with radials of your choice (that they also sell), that could well be your answer and also get a written statement of compatibility too, possibly. Might even see if you can talk to Corky himself. Radial tires do put different forces into the rim that bias ply tires do not and some wheels might tolerate it better than others. Without knowing all of the specifics on the alleged failures, it would be hard to make a determination in those cases.

Just some thoughts,

NTX5467

[JohnD1956]

I did call Coker this AM. They also said they have not heard of this. Further, they said Wheel Vintiques manufactures their wheels and that they have sold uncountable sets of these wheels with Radial tires, and not have had a problem. So I'm thinking whatever happend to the car in the other thread, had to be a long shot. Maybe they were "Friday" wheels and were never completed properly, Maybe there was a spoke from a faulty casting which broke and caused others to fail? Who knows. I am still interested in others direct experiences. Maybe some people have had failures and not contacted their supplier.

I, for one, drove my car from Albany NY to Flint and back last year with the wheels, and my older radial tires. I did not notice any problem I could pin on the tires or wheels. I did have a few other problems which resulted in a poor ride quality, but it did not seem to be flexing of the tire causing any problems. I'm just thinking of getting a 75 series radial tire and trying it again. It will be rare, if ever, that I will drive that car across country again.

[Guest John Chapman]

Could it be that 4500 pounds of station wagon and 5-600 pounds of static tounge weight of the Airstream, plus the rolling mass of the rig exceeded the design limits of the wheels?

JMC

[NTX5467]

I believe that all aftermarket wheels are built to the SEMA 5-1 specs (tested to 5 times OEM specs) or they used to. One of the areas that SEMA first "approved" was aftermarket wheels back in the early 1960s. Back then, there were good brands and not so good brands. Hence, the "Meets SEMA 5-1 Spec" became a huge marketing advantage for aftermarket wheels that everyone in the industry ended up adopting pretty quickly as their manufacturing standards.

Just some thoughts,

NTX5467

[Centurion]

JohnD1956, I know that your question relates specifically to the Wheel Vintiques Skylark-style wire wheels. In general, I have become aware of growing concerns about the use of radial tires on wheels that were originally designed for use with bias tires.

A recent issue of "Old Cars Weekly" evidently included the following comments:

"Rims for bias ply tires cannot use radials, and bias and simple radial ply rims cannot be used for disc brakes... The rims over flex as they are unable to handle the forces of the radial tires. This over flexing also means metal fatigue, breakage (most commonly rim bead edge separation) and deadly accidents".

The article suggests that loosing hubcaps is an indicator of rim over flexing.

Yesterday, my chapter hosted the BCA National Board meeting in Seattle, and there was an extensive discussion regarding the points deduction for radial tires on the older cars. It was pointed out that it is very unfortunate that radial tires have been touted as a "safety" improvement. I was unable to hear the full discussion, but the BCA's Chief Judge presented some very persuasive information that is consistent with the comments from "Old Cars Weekly". Some of my fellow chapter members left the meeting with strong interest in switching back to the bias ply tires for their vintage Buicks. I will try to learn more specific information, and will reply again to this post if I learn something more.

It would be helpful to obtain some definitive responses on this subject.

[Guest tin_knocker]

Centurion, I read the same article. I was considering putting radials on my 37 Special. The article refers to a car throwing its wheel covers after installing radials. This makes me think that it is a much newer car than mine and driven faster and harder than I would drive a car that is 67 years old. I am sure that someone out there has experience in this matter and I would be overjoyed if they would set me straight. It does seem that radials would improve handling and improve my miserable 10 mpg. However, my life is worth something to me and would probably take precedence.

[NTX5467]

Wheel flex is much more prevalent on stamped steel wheels, I suspect, than might be realized. Many middle 1960s Chrysler 14" wheels even had "travel limit" bumps and corresponding tangs on the inside of the wheel covers to match them and limit wheel cover turning that could overflex the valve stem. Remember some of the 1960s car chases where a front wheel cover flew off the wheel in the middle of a fast corner? Sure it could have been rigged that way, but probably not.

When radials came into wider use in the middle 1960s, many people put them on 1960s era cars (they were too expensive to put on an older car) with no reported wheel problems that I heard about. Main issues were the rougher ride on some cars, which was smoothed out when they swapped the radials for belted-bias ply tires.

Dallas vintage tire dealer Wallace Wade has also mentioned that older cars should not have radial tires on their older wheels due to the wheel splitting issue. I knew lots of people that put radials on middle 1960s and newer cars that came with bias ply or bias-belted tires from the factory with no wheel problems at all.

Maybe this issue is more prevalent with wheels made in the 1950s and earlier? I would also like to see some definitive failure information on this issue. Maybe there was some assembly procedures that were changed or something similar?

I do know that heavy duty truck wheels were stamped "For Radial Tire Use" or "Not Approved For Radial Tires" in the 1970s before radials were in more common use on those vehicles. I don't recall seeing anything about what made the wheels different in design, materials, or assembly techniques, but it was a big deal for the heavy duty truck people.

Perhaps some more in-depth investigation with wheel manufacturing operatives might make a good tech article for "The Bugle"?

Waiting for more information . . .

NTX5467

[JohnD1956]

I understand that the Jan 22nd issue of Old Cars Weekly had an article on this, but I don't subscribe and I couldn't find a way to get a copy online. I would like to see this and hear what it says. But the Coker people seemed VERY sure that the new skylark rims were sufficient for radials.

On my 56, the center of the wheel on my spare tire is rivited to the rim, but the rim itself is welded so smooth I can't see a seam. Maybe there is concern about the rivits giving way under the stress from the radials?

I do have radials on these rims. And, I did have a hubcap that kept coming off my front drivers side, but when I changed that cap and put it in the back, neither that one nor the one I put in the front ever flew off again. Then I drove over a rail road crossing and the bead split off the rim.

That may have been caused by my antique auto battery . It had overflowed and dripped on the wheel which I hadn't noticed for a long time.

I hope you can find the extra information. I was trying to buy a second set of tires so that I can put the wires on for the driving season and then swap them with the steel wheels for the storage season, without all the hassel of swaping tires all the time. I hope someone has some definitive information on this soon, so we can all avoid wasting any more money on something that actually increases risks.

Thanks to everyone for their posts.

[Guest imported_bjr]

I have Wheel Vintiques repro Skylark wire wheels on my 54 Special convertible with radial tires. I have driven the car for 3 years like this and have no problems. I do not drive the car hard as it corners like crap, (lots of body roll) compared to newer cars. I do however drive it at freeway speeds 70+ MPH. I would not worry about wheel breakage with these wheels, but there may be problems with the original Skylark wheels with radial tires as others have mentioned. Brian

[Judd]

Brian

I drove my 56 to Chicago from the Mississippi Gulf Coast and back in October at interstate speeds ( 11 hour trip each way ) with Diamond Back Classic radials on stock 56 wheels with out problem. I have had problems with Coker radials along with several other people and wouldn't put much stock in their opinion personaly.

Judd

[Guest brh]

I have had 2 sets of radials on my 65 since 1974. I have never experienced a problem except the ride changing. As far as speed goes, I have a lead foot. The car had bias ply originally, and the steel rims are stamped with spinner wheel covers. Just my 2 cents.

[Guest scott mich bca # 6619]

I had nothing but trouble with my radials on my 1955 Roadmaster on the original Kelsey Hayes wheels. The spokes loosened up every year 4 years in a row.

The rode, handled and looked excellent, but too many problems.

I had the wheels rebuilt, and put the proper bias ply tires on the freshly rebuilt rims and no problems. I drove the car to Flint and back from Chicago.

With the proper alignment and a freshly rebuilt front end, it handles remakably well. I thought it would be a lot worse. I would say approx. 80% as well as radials.

You may never experience a problem with radials on old bias ply rims, until you have to do a very hard maneuver and they come apart.

I also considered the Vintiques, but the warranty was fairly short, and I could not find anybody that had actualy owned them, or could talk independently and unbiased about them, besides the manufacturer.

I have a copy of the Old Cars Article if anybody needs it.

Scott Mich BCA # 6619

scott@earlmich.com

[JohnD1956]

There was a lot of talk about this Radial/ rim situation on the Riviera club maillist. And I finally saw that article. I'm no longer convinced that this article even applies to GM cars. It appeared all the sources for the article were driving mopars, of early 60's vintage. Call me whatever you like, but I wouldn't doubt that early Chrysler rims were under engineered. But my 56 Buick rims seem quite sturdy, and the Wheel Vintiques wheels seem even better.

I called the Wheels people two times on this. I wound up speaking to Don who personally set up and supervised the construction of these remakes over the last ten years. He told me that the wheels are trued using pneumatic screwdrivers. He said the spokes are so tight on these new wheels that they can hardly be twisted by use of a wrench. He also claimed to have no knowledge of anyone having any problem with their wheels and radials.

I also called Coker tire, who claimed they never heard of anyone having such a problem with these wheels.

Since you had trouble with original Kelsey Hayes wheels, I think I'm going to try the radials again. Bias ply tires seem way out of line in terms of cost. Plus unless you go for a trailer tire, apparently you cannot get a bias ply tire in a blackwall. On the plus side, you can get a trailer tire in a six ply configuration size 225 X 15 ( which Coker said was the closest exchange for my 7.60 X 15's, at our local Firestone dealer for about $80.00 per tire. They are supposed to be bringing one in so I can see what the tread design looks like. But i still think I'm going for the radials.

[The Old Guy]

I have driven my 1940 Super 100,000 miles on bias tires. It is true that you have to pay a little more attention to the road with them, and they don't run 40,000 miles,but if you are really concerned about safety, you really have two choices. You can run the bias tire and drive the car, or you can replace the wheels with an aftermarket unit and do away with the originality of your Buick. I followed a friend to a meet some years ago, and he had new rarials on his 1958 Limited. We got 80-90 miles from home and a rim split at the bead. We installed his spare, and on the way home, he split another. I put radials on my 1957 Caballero, but I used the later road wheels. One of the problem for the early Buicks is that the center hole is too large to accept later wheels.You can have the center machined out but unless you have access to a BIG lathe, it is expensive.

Just my .02

[55PackardGuy]

Hey, Guy,

If you're truly "old," you must have driven in the years when radials were being introduced in the '70s, and could make some "side by side" comparisons like I did. For my money, I always preferred the bias ply tires in those days for HANDLING. The radials gave most cars a "wallowing" feeling. Remember the "radial tuned suspensions" that came out to compensate for this? That seemed to help some. But I had a '73 Opel Manta that came with bias ply tires. When I "upgraded" to a good set of radials, I was disappointed that they gave the same "mushy" feeling, even though the car supposedly should have benefitted greatly from them. I might have been able to corner a little faster, but the car didn't seem to respond as quickly to steering input.

Also, do you recall all the problems they had with high-speed failure of the radials? I remember that police cars did not adopt them for many years, and I think that was the reason. They've improved them--at least they don't fly apart like the old ones sometimes did--but they still are careful to "speed rate" them to discourage high speed use. No such warnings that I know of on bias tires.

Some of the belted bias tires were junk, as they only had two-ply sidewalls and the belts sometimes slipped. But if I could find some good ol' 4 or 6 ply bias tires for my Dakota, I think I'd like to try them.

[The Old Guy]

Guy, you are right! It took me a long time to get used to radials. The thing I noted most was that with a bias tire,you could get the car loose and drift the corners ,and you knew what the car was going to do. the radials would hang on a little better, but when the car got loose you couldn't get it back.

[NTX5467]

One of the reasons that law enforcement operatives did not jump on the radial bandwagon, in spite of the BFG Radial 990 advertisement of a masked police officer telling how they'd hang in the corners to keep the world safe from speeders and other 'ner-do-wells, was plain and simple--cost. Just like Rochester RamJet Fuel Injection was just too costly for the benefits received (lots of money for only 10 horsepower over a Holley 3310, for example, on a 1965 Corvette).

The other reason many performance-oriented drivers did not like them was the sudden break-away at the limit of adhesion, as mentioned. Bias ply and bias-belted were very predictable and exploitable in their "at the edge" characteristics. I always considered the bias-belted tires to be the best compromise until the cost of radials decreasing and economic prosperity rising made them viable alternatives for everyday people.

From those early days of real 4-ply tires (even nylon) and the old Michelin X radial, things have changed markedly. I always suspect the soft sidewalls on a radial would cause the lateral sway mentioned, but I never saw it to the degree it might have been. Maybe the Fords and Chryslers I was riding in with radials did not have the same lateral sway characterics of GM cars that were not "Radial Tuned"?

When Pontiac came out with their touted Radial Tuned Suspension package, it made a marked difference in the lateral compliance of the suspension. For example, I could walk up to a non-radial tuned Bonneville, put my right foot on the rear bumper, then push down and sidways at the same time to compress the suspension. The car would bounce and shake like it was Jello. Doing the same thing with a radial-tuned Bonneville resulted in basically up and down body movement. Whether all of the firmess that came was in different suspension bushing rubber compounding or in the added rear sway bar and firmer shocks, could be debated.

Not to talk bad about GM's approach to a smooth ride, but they did seem to have more later compliance in their rear suspensions that Ford or Chrysler did. Ford, notably, as they had coil spring suspensions on the rear whereas Chrysler had their leaf springs. In some cases with the older GM full size cars, you could watch them sway as they came to a stop.

Where the bushings had to be retuned was to compensate for the higher impact harshness that radials put into the chassis at certain speed ranges. Adding the rear sway bar and firmer shocks/springs further exploited the handling capabilities.

When P-metric radials came out with their higher 35psi max pressure for 4-ply rated or "Standard Load" ratings, the radial started evolving into a different tire. Used to be that if you leaned on one of the older radials (1970s time frame) when unmounted, the sidewalls would collapse as the tread stayed flat on the floor. A bias-ply would basically fold up under your weight. Current radials, at least to me, seem to be quite a bit difference as when you lean on an unmounted tire, the tread buckles as the sidewalls do too. And then there were the original Gatorbacks that were similar to bricks in their resistance to deflection. So, in some aspects, radials are similar but not the same to the older ones of the 1970s--plus being about 5 pounds/tire lighter in the process.

Pirelli had a tire in the middle 1970s, the P76 which they claimed was tuned for American cars and the way Americans drove. A neat tire that offered ride and performance, but it was not as widely accepted as the Michelins were. It was even rated for police duty on middle 1970s Dodge/Plymouth mid-size police packages.

I have the gut feeling that if you took a bias-belted tire's tread belt, put it on a radial ply tire carcass, took about 5 pounds out of the sidewalls, you'd have something pretty close to the modern radial tire.

To me, if you're not chasing trophies in shows that demand "as produced originality" to the max, then whatever's reasonably priced and available (should you need assistance on a trip) and works on the car would be the optimum tire to use for the particular purchaser.

Several years ago, a work associate was asked a question about what tire to buy. He immediately started extolling the virtues of Michelins, which is fine, but in our line of work that can be very dangerous as it could come back to haunt in the future.

I replied to him that the typical "little old lady" that only goes to church and to the store each week did not necessarily need to spend $100.00/tire for Michelins with a life expectance of 80,000 miles. By the time she had put that many miles on the car (if she still had the car), they'd be so weather cracked to not really be safe to drive. If, with only about 30,000 miles, one went flat due to dry-rot, she'd probably be chasing that young feller that told her how great those high priced tires were! This gets to the shelf life issues that were mentioned in a recent 1956 Golden Hawk Registry newsletter "56J".

Back in the early 1970s, I spent some free time at the Exxon service station of a friend's dad. He had one Exxon landman (or similar) that traded with him. At that time, they had a company policy that when company car tires accumulated 30,000 miles, get a new set of Exxon tires (the belted-bias of that era, which were made by Kelly Springfield). Something their safety department dictated, he said. Mr. Green didn't mind as it gave him a good set of used tires to sell.

As the repro bias ply tires can wear to the neighborhood of 30,000 miles with decent care and use, that's going to be about 5+ years of use anyway. If they're right for the car and it feels right with them, then go that way. Even at 10,000 miles/year, that's three years of enjoyment.

Sure, radials have their better wet traction and cornering power, but do we really drive our collector cars that way any more? By the same token, running the bias ply tires at the 30psi inflation pressure range, they will handle markedly better than at the "soft ride" 24psi, but probably ride a little firmer as they last longer too.

In general, radials will make a better handling/riding/performing vehicle, but it doesn't always work that way. Of course, as we've mentioned, the condition of the suspension bushings and steering components can make more difference than just the tires themselves. Afterall, bias ply tires are all that we had to drive on for years and we survived that, just like surviving without cupholders or cell phones. Might have been that we just didn't know any better?

Many things have changed markedly since the early/middle 1970s. Tires and shock absorbers are just a few of these. Just because a technology is newer doesn't make it better in all instances, by my observation.

Enjoy!

NTX5467

[Matt Harwood]

NTX, your vast knowledge of things automotive never fails to amaze me. I'm still sitting on the fence whether to put radials on my '41, but your post makes me believe that I'll be happier with the original-style bias-ply wide whites, which will not only look right, but will probably "feel" right on a vintage car like mine.

Thanks for the insight.

[55PackardGuy]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Bias ply and bias-belted were very predictable and exploitable in their "at the edge" characteristics.</div></div>

NTX,

This statement perfectly captures what I was trying to say about my preferences for the handling of the old bias ply tires. There was an "exploitable" notch that just felt really comfortable for the yahoo way I drove. I had a '65 Electra and my dad always made sure our cars had decent tires, usually slightly "oversized" 4-ply Hood brand. (Are those around any more?) I usually ran from 30 to 35 psi all the way around. It didn't make it into a sports car, but that big Buick was surprisingly agile. I drove a lot of dirt roads and could do some very fancy "power slides" and trailing throttle stuff without ever spinning out or losing control.

My dad, a mechanic, was never a friend of belted tires. As I recall, the basic structure of these was 2 ply, with one or two belts to put extra plies under the tread. He considered the side walls too flimsy. Your comments on the advantages of these are interesting.

I kinda thought, as you said, that police departments were looking to get by a little cheaper, as well as avoiding high-speed blowouts (or just losing hubcaps ). It might've been a false economy though, because of greater longevity with the radials. I imagine they researched it and decided that the radials didn't justify themselves for cost and/or safety reasons.

SO, does anyone still make bias tires other than to match collector car OEM specs? Like I said, I wouldn't mind a set that would fit my 15" truck wheels which now have 235 75R Goodyears. Also, I love the old "red stripes," "wide ovals" and other performance tires of the '70s. They'd be Something Different for my Camaro.

Finally, one thing we haven't mentioned much is Braking. Are bias tires at a serious disadvantage for panic stops, wet-surface braking, etc?

[NTX5467]

As you might recall, when the bias ply tire's tread surface contacts the road surface, the tread will flex. This flex usually results in the outer edges carrying most of the weight if the inflation pressure is too low or the inner portion if the pressure is too high. Braking will only make for more flex on the front tire's contact patch. Higher pressure can help in this respect--to a certain point. Radials or bias-belted tires will keep the contact patch flat due to the added stiffness in the tread area from the belt. The added stability in the contact patch area is also why wet weather and snow traction is usually better with a radial or belted tire by the tread staying open.

Other than those engineering aspects of a tire's braking performance, it gets to be more related to rubber compounding and frictional coefficients between the tire and the road surface.

Remember those early Goodyear PolyGlas ads where the announcer took a gum eraser and rubbed it on the asphalt roadway? Everytime a tire rotates, the bias ply tire's tread is squirming against the roadway. Keeping the tread more stable decreased the squirm and enhanced tread life, handling, braking, etc. Taking the squirm out of the tire's tread area allowed for rubber compounds that were more performance oriented but would have better wear characteristics, kind of like a "best of both worlds" situation, unlike the former "hot tip" butyl rubber compounds that stuck well but had short tread life (Atlas Bucrons and similar, for example). Taking the flex out of the tread also took heat from the plies flexing against each other out of the mix too, multiplying the possibilities with the rubber compounds and leading to longer tread life.

I mentioned "feel". A prime example might be my '77 Camaro. I did the upgrades to the Firebird WS-6 sway bars, Z-28 steel wheels, and KONI shocks. After a year or so, I found the wheels as take-offs as the stock 14" wheels/tires made the front valence panel spoiler vulnerable to curbs way too much. The first shock upgrade I did was to Delco 501 Big D shocks. Then came the BFG Radial T/As in the P225/70R-15 size and the KONIs were swapped off of a friend's '78 Z-28 the night before he traded it off. The combination of BFGs and KONIs gave the car a nice, gutsy feel and still rode well plus handled better by a big margin.

Then Pirelli came out with some P77 Radials. Assymetrical tread and compounding too. An H-rated all season radial. I found a place in Dallas that had them and took my wheels over one Saturday and got them mounted, replacing the OEM-spec UniRoyals that '81 Z-28s came with. The Pirellis felt good on there and I was happy--until things got a little too soft and I adjusted the KONIs to get things firmed back up again.

I had two sets of the Pirellis on the car and never could get them to feel firm like they used to with the BFGs. Rode like a Caprice, handled great, but just a little too soft. Other problem was weather cracking, even with protectants. One day I came out to go to lunch and saw stainless steel smiling at me from between the tread ribs--yikes. When I put the BFGs on it, the gutsy feel returned immediately and I have not put anything else on there since. Last set of BFGs went over 90,000 miles too.

What I suppose was going on is that the rubber compounds and other things inside the Pirellis were filtering out the little stuff so the shocks thought they were a smooth interstate all the time, hence no firming up when they might otherwise kick into the high-speed valving activity for added firmness and "control".

On a '67 Chrysler Newport I have, I needed to buy some tires after one of the tires that were on the car when I got it went south one night on the way home. I searched for a radial equivalent of the H78-14 and finally found some Kelly-Springfields that would do that. They did ok, but not quite what I knew it should be. I then bought some P245/70R-14 BFG Advantage T/A whitewalls from Coker (measured out as an exact match to the old H70-14 size!). As the Chryslers were supposed to be more sensitive to radial harshness, I bought the BFGs (and the previous K-S were glass belted radials) as they were all fabric instead of fabric/steel--plus the BFGs were 6-ply rated. I felt the fabric composition might be better in the long run too (this was in the later 1970s when steel belted radials were having some problems).

With those BFGs and their stiffer sidewalls, the car felt better. Never did document any better fuel economy, but it seems to take much more effort to push it around in the driveway than it does my Camaro with the later BFGs on it.

If you get into the guts of modern tire design, the more performance-oriented radial tires seem to have bead area stiffeners and a decreased flex area in the sidewall area. Plus a stiffer tread area than the other more mainstream tires (including the outer "cap" over the tread area's belt for added capabilities). Higher speed rated tires usually have these features rather than the basic S-rated tires unless they are like the Radial T/As and have some performance pedigree. Looking at the various tire websites can reveal these little differences.

I noticed that Coker will have some higher speed rated bias ply tires in the near future. That ought to be interesting! Certainly will be a compliment to their existing muscle car Wide Ovals and PolyGlas GTs and other period red-stripe tires.

From what I observed, the belted-bias ply tires were basically a two-ply tire with the added two plies of tread belting that resulted in a 4-ply tread area. There was always some debate of whether the 4-ply (4 smaller diameter cord plies) or 2-ply (2 larger diameter cord plies) were best. The stronger nylon usually went with the 4-ply tires whereas smoooother riding Rayon was in the 2-ply tires with Polyester being the best cross of characteristics regardless of how many plies the tire had (that was middle 1960s and later). Hence the name "PolyGlas" from polyester basic carcass plies with fiberglass plies for the tread-stiffening belt under the tread or "PolySteel" with steel belts replacing the fiberglass belt material. Seems like Firestone had some low profile performance tires that were bias-belted but with steel belts. Lots of choices!

Back to tire pressures for a moment. In the older Chrysler owner's manuals, like other manufacturers, they usually spec'd lower pressure for the front tires than the rear in the basic "minimum" inflation pressure. But what they added was a spec for "high speed driving", when the basic spec was raised by 4psi. That meant a base inflation pressure of 28psi. What I did from there was to figure the weight distribution (usually 55 frt/45 rear for most of the full size and mid-size cars in the '60s and '70s). The extra front weight bias would mean more pressure so that all tires have the same proportional part of the total weight reflected in their inflation pressure. That usually meant that the inflation pressure min spec ended up being 30 frt/28 rear. Having the higher pressure in the front tires also sharpened steering response and helped handling somewhat too--by my observation, plus better tread wear. Plus kept the rear tires from wearing in the middle first from having too much air for the load they were carrying. Works with radials too. Worked for me, but proceed at your own risk.

Enjoy!

NTX5467

[55PackardGuy]

Wow! For some people that might be "too much information" but for me it was fascinating. That lower-rear higher-front inflation scenario makes so much common sense, especially for vehicles that are much lighter in back, like pickups!

Is Coker the only place manufacturing red-stripe or wide oval tires? (I guess I should stop asking so many questions and start doing some research on my own.)

It's particularly good to read information that comes from EXPERIENCE. Just about everything you listed comes from personal testing as well as theory.

The "tire world" is so fickle and it seems like if you go into stores, they just want to sell you the latest fad. When I bought a set of Firestone Firehawks for my '95 T-Bird, I had to talk the guy into selling them to me. I confess I bought them mostly on looks, but also because they'd been around awhile (he claimed they were an "old design.') Well, guess what? They worked GREAT. Car handled better, rode fine, sat a little lower and they looked great. (I put 'em on with the "boy racer" raised letters showing. )

I hope others are getting ideas from this thread about putting the right rubber on their own vehicles. There are a lot of options, and sometimes it takes trial and error, but it's nice to read about what people have tried and how it worked. Sort of narrows things down and allows you to make a better "judgment call."

[jerryacheson]

You may want to check Diamond Back. They custom made mine. I'm putting 1" ww radials on my Cragar wires. You can get to them at www.widewhitewalltires.com