Recommendations on Street/Track Tires

[shelbydoug]

Shelbydoug - those tires seem to fit nicely! What are the rim widths and backspacing on those 10 spokes? I assume they are 15's?


Do you have stock brakes? The reason I ask is that mine has Wilwoods all around and need a little bit more clearance for the calipers.


~Kevin

Ah hah! Welcome to my web say the spider.

To answer your questions.

1) No, the brakes are not stock.
2) The front wheels are reproduction 15 x 7 Shelby 10 spokes
3) the rear wheels are early 15x7 original 10 spokes

Explanations:

1) The front brakes are what are referred to as Shelby Trans-Am brakes. What that means is that at some point in Shelby's production of Trans Am Mustang race cars, they enlarged the front disc brakes using the 67 Galaxie/Thunderbird/Lincoln brake calipers and 12"x 1.25" vented rotors.

To use that on a Mustang it requires a special adapter and a switch to the production 68 BIG diameter drum brake spindles.

This is what is on the front of my car, i.e., vintage legal Trans-Am front disc brakes.


2) The rear. What I initially wanted was a rear disc brake set up. WELL before virtually ANY of the current aftermarket kits existed, I discovered the 76-78 Lincoln Versalles disc brake assembly.

If you are unfamiliar with this entire rear assembly, the entire thing is unique. It mounts a unique caliper, via a unique adapter welded to a unique 9" rear banjo.

It is narrower then the stock 67-8 banjo by 2" (and the same width as the 65-66 banjo) BUT the spring perches match up exactly to the 67-8 springs. It's a bolt in.

So the effect of using this rear is to move the outer edge of the tire inboard a full one inch. The effect of the clearance is shown in the picture I posted. You can put your hand between the fender lip and the edge of the tire.

That's a full 12" tread plus the thickness of the sidewall. It tucks in so nice, most people miss the detail and think it is stock.

Now the only change that I made to the Lincoln rear was to change from the 28 spline Ford axles to 31 spline Strange axles.

So you might see my interest in this tire discussion going on here. Replacing the BFG's with the Avon's disguised as Goodyear blue streaks? Then again, maybe not.

The Lincoln rear is already equiped with a parking brake, again of a unique design and what makes people crazy is the big FORD script that they see when the wheel is off. Lots of head scratching.

..and yes, there are Porterfield R4S "street pads" on it.

When my trunk is open, pay no attention to that blue bottle in the corner, it ain't nothing important. 

[CSX2259]

John, when you shave the Avon sidewall to clean it up, is it smooth or slightly scuffed in texture?

It is smooth, the process is a multi step procedure that removes original tire sidewall details and allows us to apply the requested graphics or striping. The sidewall treatment is up to our clients, stripe, no stripe, "Polyglass script" can also be applied as well as other manufacturers logos.

[kjspeed]

John Barnes indicated that my car has the "big" front spindles, so that may mean he used the drum spindles. Using the narrower Lincoln rear end would definitely help tuck the tires under. Mine is the stock width Mustang housing but with Wilwood disks, Moser 31 spline axles and a 4 pinion diff. I could tuck the tires under further by using wheels with 1" more back-spacing. These aluminum ones I have measure 3.75". It would be nice to get more rubber out back than a 225/60R15. The Avon CR6ZZ's jump from 225/60 to 245/60 to 275/55 to 295/50 as far as I can tell from the dealer sites.

[427heaven]

Now we are deviating from tires, to car modifications for a car that will see little track time. There is a whole bunch of track modifications that could put a smile on your face but as you stated you were just looking for a little more grip. Take your car out to a few open track sessions and see if you want to make your car more track worthy or just put a set of STICKIES on it for that occasional outing. That will help guide you...

[shelbydoug]

John Barnes indicated that my car has the "big" front spindles, so that may mean he used the drum spindles. Using the narrower Lincoln rear end would definitely help tuck the tires under. Mine is the stock width Mustang housing but with Wilwood disks, Moser 31 spline axles and a 4 pinion diff. I could tuck the tires under further by using wheels with 1" more back-spacing. These aluminum ones I have measure 3.75". It would be nice to get more rubber out back than a 225/60R15. The Avon CR6ZZ's jump from 225/60 to 245/60 to 275/55 to 295/50 as far as I can tell from the dealer sites.

You can't use the drum spindles with the Ford disc brake calipers. One of the reasons to go to the
Tbird calipers is that they have four pistons vs. one for the 68 Calipers. They are also huge and increase the clamping force on the rotor.

The caution on the rear change is that there is a maximum you can go to with negative offset on the wheel. What will happen is that you will eliminate the tire interference on the fender lip but you will get tire interference on the inner fender side.

Using the early 67 15" ten spokes, there is an additional 1/4" backspacing to gain over the later ones with the cast in wheel spacer.

I also doubled the long upper leaf spring. If you investigate, you will find that most of the "R" models did that as well. The difference with them was that they mostly used the Koni rear shock.
I found that a MUCH better shock to use was the Cure-ride.

It's a bigger piston then the Koni and as a result with the other changes, the car is smooth in the rear rather then harsh.

If you want to make these cars handle, I think that's the way to go.

Also, regardless of what the factory did with the Boss 302's, a rear anti-sway bars on these cars is a no-no. Frankly, use the 1-1/8" front bar (from the Granada), konis in front, the "trans-am" cut down coils in front and you eliminate the need for one.

I disagree that this is a departure from the intent of the original poster. The intent was what to do with the rear in particular and the Avon's appear to be a plus BUT under certain conditions AND what I just listed is a way to make the car ride like a Lincoln and handle as well ON THE STREET.

It just spills over on to the track and unless the car had these mods, you'd never know what you were missing. You would be saying to your passenger, "the cars are light in the ass. That's why they hop all over the place like this". That's your choice. Not mine. 

John stayed with that set up because of the LOOK of the Goodyears. Frankly that's all they are good for, the look. They don't belong on the street and certainly are a handful on the track needlessly, if not lethal?

[2112]

If you are not doing concours, you can solve a lot of problems like they did in the 60's and 70's;

[1109RWHP]

You can use drum spindles with the Ford Kelsey Hayes T Bird calipers. I have 70 drum spindles, custom caliper bracket, 67 Mustang disc brake hubs, 69 LTD rotors and 67 T bird  calipers. You need 70 outer tie rods to use the 70 spindles on an older car that has the smaller tie rod end. Cobra Automotive and Street or Track sell the bracket.

[98SVT - was 06GT]

I really appreciate the feedback gentlemen! I hadn't given a thought to the mags not passing tech because of age. I did check for cracks but wasn't aware that magnesium got more brittle with age. So....

When I was crewing on 5R001 I sprayed a wheel to clean it and saw a neat row of bubbles coming out of a crack that went all the way around the spoke. These had been crack checked about 6 months earlier.

[zray]

"........Also, regardless of what the factory did with the Boss 302's, a rear anti-sway bars on these cars is a no-no. ......."

^^^^^^^^

I have yet to see a rear sway bar (on a 65/66) that actually helped anything.

Z

[427heaven]

^^^^^   The big AADCO 3/4 inch bar works best...  And away go body roll troubles down the drain. Ask Cobra automotive they run the bars.

[shelbydoug]

^^^^^   The big AADCO 3/4 inch bar works best...  And away go body roll troubles down the drain. Ask Cobra automotive they run the bars.

I can't disagree with how they set up THEIR cars.

I have had my car since April 4, 1972. It has had close to every possible combination on it that ever existed.

IN MY CASE, a 3/4" REAR bar IN ADDITION to everything else, made it close to impossible to even go through the "eSSes".

Take it off and you can steer through with one finger on the steering wheel.

In my case, I AM NOT an alchemist. I can't speak for the Curt and his crew.

The minimal I can say is, you do not need a rear bar. In my case though the addition of the rear bar was DETRIMENTAL.

[zray]

"......In my case, I AM NOT an alchemist. I can't speak for the Curt and his crew......."

I think alchemist misses the mark a little.

at any given time they they are best described as spell-casting sorcerers, witches riding 500+ HP brooms, or wicked warlocks with 0w-50 in their veins, and in any case,  always capable of inducing mass hypnosis at any given racetrack, if you get in their way.

Like this

or this photo of Curt & crew, shape shifting, and having a slow driver for lunch

Z.

[shelbydoug]

It is my understanding that an alchemist is one who attempts to change lead into gold.

That is not the same thing as a survivalist. There are survivalists that insist that eating raw meat is essential to keeping ones resistance as high as possible. If that's the way they feel, that's their choice. I'll just stay out of the way. 

Your pictures are showing a pack of wolves and/or wild animals consuming a deer. You sound like a competitor to the Cobra Automotive prepared cars which have often called foul. Kind of like the Corvette racers did when the Cobras showed up.

It was said that they would actually cry, say the Cobras had an unfair advantage, not even take the Corvette off of the trailers and just turned around and went home.

I'm sure that knowing Curt, that is a level he aims to achieve? He will probably take those pictures as a compliment and the Corvette racers as a reminder?

[zray]

the symbolism in the photos is not that that hard to follow. The friends I cared for for many years are just doing the same thing Curt does on the track; dealing with a creature who was just too slow to survive.

Not complicated.


Z

[shelbydoug]

the symbolism in the photos is not that that hard to follow. The friends I cared for for many years are just doing the same thing Curt does on the track; dealing with a creature who was just too slow to survive.

Not complicated.


Z

Sorry. I guess I am just to simple and don't see it? Me bad.