The Snowball effect of a blown tire. - Printable Version

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The Snowball effect of a blown tire. - Carolina_Mountain_Mustangs - 07-04-2019

We all know how working on one of these cars runs into what I call the Snowball effect. You start with one little thing that turns up two more that turns up 4 more projects.
Well last Saturday I took the 73 vert on it's longest trip to Charlotte to the MOM for a show and to check on the Mach 1 in the museum.
It was blazing hot and I was running down I-85 going 70+ at times. I do not know how old the tires are on the car got them off the crashed vert I bought about 3 years ago. The are Kelley tires made in South Africa so not a great quality product but they looked good and period correct narrow white walls. I had polished up and restored a set of 4 Sport Wheel cover took 11 covers to make 4 decent ones. Hours and hours of polishing and masking off to refinish the argent paint.
So just at the exit for the MOM the car starts to shake violently and I slow way down. I take my exit and pull into a Wendy's parking lot and boom the right front tire has steel belts sticking out. So I limp the couple miles to the MOM and park at the show and get out and watch the tire go flat.
Steve, runs the museum, came over and told me where the closest tire store was. I spent a couple hours in the museum wiped down the Mach 1 and talked to some of the show entrants. I packed up about 1:00 and headed to find a spare tire. There were no 14" tires to be found in Charlotte. Nobody keeps them in stock have to order them due to no demand. So I headed home and reduced speed to 55 with no spare.
To keep the tires matching I need a new set of 4 tires and probably should get 5 in case it happens again. So I decide to keep the other three good tires for rollers and polish another set of the forged aluminum wheels for the 73. I pick through the one's I have and pick the 4 best.
It takes about 8 hours to get 4 wheels ready to polish. File the rough spots, clean all the tar off and the back side of three of these had been painted so that took forever to get off. Have several sizes of wire brushes to get into all the areas on the back and special care of the bead lock area so they do not leak.
I got the 4 cleaned and ran one through the blast cabinet to even out the look of the back side.
Then to the drafting table to sand with 1,000 grit and water and then polish. I get the buffing heads at Harbor Freight, cheap but will do 4 wheels then toss. So got one polished yesterday will do the other three today and decide if I want to do one more for spare that I can rotate out just in case.
Oh btw the spare in the vert had never been on the ground so before I went to the MOM I swapped it out for another roller. Glad I did a 46 year old tire might be a little fragile. Looks good at show though.
It was almost 100 deg. and the 351 C with .050" over bore, came, flat top pistons and AC did not have any heat issues, hurray. I had installed a Hayden transmission oil cooler to take a little more heat out of the radiator. At least now I have some confidence in longer trips in the car. Sat for 27 years because the PO had put the R.H. head gasket on backwards.
When I looked up the tire size for an F-70 X 14" the chart said 205 but I know the tires on the steel wheels were 215. Can you push it any farther with only a 6" wide wheel or are they going to round out? Going to go with just the Cooper Cobras this is not a show car my driver.
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RE: The Snowball effect of a blown tire. - Don C - 07-04-2019

The section width of a 225 is approximately 1/2" wider than an F70, so that shouldn't bulge too much. The ideal rim width for a 225 is about 6.5", so not that much difference. One chart I have shows a 225 as being a replacement for an F70, while another one has it as a 195.

RE: The Snowball effect of a blown tire. - 7173Vert - 07-04-2019

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I have these tires on my '73 vert. 215/70/R14" I personally would not go larger then this on these rims, plus, they look fine.

RE: The Snowball effect of a blown tire. - Hemikiller - 07-05-2019

This is what I would consider a teachable moment. Always check the DOT date codes on tires if you din't purchase them yourself. Lots of these cars get driven very little and just because the tires "look fine" doesn't mean a darn thing. The tires I just pulled off my 71 were bought from Tire Rack in 2007. They look as good as the day they were put on, but by driving them I could tell they were not. Manufacturers recommend replacing tires over 6 years old. A set of tires is lots cheaper than repairing bodywork if one blows and takes out a quarter panel, or causes an accident.


This is what I use to cross to radial tire sizes.

E70 - 215/70
F70 - 225/70
F60 - 245/60

Section width is more or less irrelevant due to the construction differences between radial and bias/belted tires. Best match is simply to go with the correct diameter and aspect ratio.

Firestone Wide Oval F70-14 is 26.2" diameter


Cooper Cobra 225/70R14 is 26.3" diameter


I ran 225/70s on my stock steel 7" wheels. They fit and looked fine. Upgraded to 15" rims and have Cooper Cobras on now. BFG are about $50 more per tire and not worth the cost IMO.

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RE: The Snowball effect of a blown tire. - Carolina_Mountain_Mustangs - 07-05-2019

I got all of the wheels polished and done yesterday. I went into the hoard and found the last 4 NOS center caps I had. The purchase ticket was in one of the boxes. The two that came from Ford part # D3ZZ-1130-A had a list price of $18.90 and my price back in 1981 was $14.00. They were the three screw version by then. The other two I had were 5 screw and I guess I got at a swap meet price on box is $50.00 each I probably paid a little less.
So today I head to friends shop to use the Bridgeport mill to drill the broken screws out. I did soak them in P oil hope they screw out when I start drilling from back.
I will use SS screws going back.
Then off to Discount Tire to see when they can get them in. Sure they will not have in stock.
Here is a scan of the ticket. Looks like I bought couple weather strips and some kind of pad for 65 Mustang also. I was always buying stuff and putting up I knew it would go away. I think the 15 screws were for installing the ram air plenum.
On the width I will see what they say. The aluminum wheels are only 6" so not so wide.
I saw Hemikiller's note on tire age. The oldest set of tires I have on a car in the garage is the original 1950 Ford. Has it's original tires on it but they had tubes back then and they stay pumped up all the time.
My 84 mustang has some TRX tires on it from the 80's and they stay up and do not leak.
The UV light is big killer of tires and some say ozone?
That flat was my first flat in many many years. I am going to get 5 tires and get the spare to match but on steel wheel.

RE: The Snowball effect of a blown tire. - detritusmaximus - 07-05-2019

Yeah, UV, ozone, acid rain and oxygen all conspire to kill tires. Plus, the rubber itself ages, no stopping it. Sealed up in black plastic bags will extend their life. The tires will go from being nice and pliable to almost as hard as skateboard wheels and still look perfectly okay. Good for a museum or doing burnouts, but no traction.

I used to do urethane molding and casting and we would use pure nitrogen to displace the air in the containers of unmixed resin and urethane. Otherwise it would absorb moisture and crystalize. that made me think about the benefits of using nitrogen in mounted tires as a preservative (even though that is not why people generally put nitrogen in their tires)....then into a black vacuum bag.

RE: The Snowball effect of a blown tire. - Carolina_Mountain_Mustangs - 07-06-2019

So two of the wheels I polished were Maverick so the center hole is correct size to fit Mustang front hub and rear axle. The other two were for Mercury so the center hole is way larger. I will order some aluminum to turn a ring to put in the wheel so that the hubs fit. If you run these or any wheel and the center hub does not fit the front hub and center on the rear axle you can get in trouble. That is what supports the weight of the vehicle and centers the wheel the lugs just hold the wheel to the rotor or axle. If you depend on the lugs to locate they will never be on center and can work their way loose much easier. I always use a torque wrench to install and 100 - 105 ft. lbs. with some lube on the threads also.
I got all the screws drilled out one had 4 broken screws. I also recut all the seats for the lug nuts. Aluminum wheels suck in that area.
Got the SS screws for the caps but did not get by Discount tire to order the tires.
So did some trading with one of the members for a set of used lugs so at least have some to install hope to be on car next week.
If you look at the back side of the wheels Ford did some engineering on the mounting surface. There is a relief forged around each lug. They also do not have full bearing on the mounting surface some of the center area is relieved. I am thinking that allows the wheel to give and act like a lock washer to help them stay tight. Difficult to see in the picture but on the bosses around the lugs you can see like an eye brow on the outer edge above the
center line of the lug hole. From there to the center the wheel is relieved. I have 5 sets of these and all are that way so not a machining error. They all have a serial number stamped into them, see inside the triangle recess. Ford must have feared issues to come from them to do all that.
I know Cragar mags had a bad name here for the centers breaking easily and caused several friends to crash. They were cast and these are forged which should be about twice as strong.
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RE: The Snowball effect of a blown tire. - Carolina_Mountain_Mustangs - 07-10-2019

Got the new tires mounted yesterday. I used Discount tire for several reasons. Price was good, you can make an appointment and they keep it. They were very careful with the wheels and when I got home I washed them and looked for bubbles around the beads, all were good.
Got them on the vert and caps installed  Now I have to find more original lug bolts. You can use the standard nuts a socket clears in the wheels. I put the anti seize on all the screws in the center caps. Will get some pictures later.
The paint was not dry enough on the spare rim to allow them to mount it will take over on Friday and get it mounted. So I will have 5 new tires should be ok for several years.
They did not put wheels on the car but as I sat there and watched them working on the cars it is always good to see them use a real torque wrench when they tighten the lugs down.
They were putting new rims on a newer Camaro and they actually installed rings around the hubs to make the center hole fit the hubs as it should.
I have to turn two rings to go on the two rear wheels I have since they were for Mercury have a larger hole. The two fronts were off a Maverick so they are correct size and fit the hubs snuggly.
For reference the diameter of the center hole for the factory forged aluminum wheel is 2.440" - 2.441" I checked with telescoping gauge and micrometer when I recut the lug holes and drilled the broke screws out.

RE: The Snowball effect of a blown tire. - rackerm - 07-10-2019

I went with five Firestone GR70 Radials on my 73 vert. They fill the wheel well nicely and ride great, I am very happy with them. The car originally came with GR78 14s radials from the factory.

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d20 dice

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RE: The Snowball effect of a blown tire. - Carolina_Mountain_Mustangs - 07-10-2019

I did not want to spend the money for OEM type tires since this is my beater driver car. The Firestone tires had a really bad reputation back then. When I ordered my 73 I requested Goodyear and I got new ones for it to sit in the museum.
I got the tires on the car and drove around town and through some back roads. I am pleased with the ride but still have to watch it on starting or I spin the tires, lol.
225 is the widest they wanted to put on the Factory 6" rims.
Will see how they do because I will be driving this one more than most. Might come up to Michigan for the Ford show. I do need the factory lug nuts. Got 10 from one member but they came after I had the wheels on the car. I could use 40 NOS lugs if anyone has them.

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