Tire question

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Captainkirk

Captainkirk

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My son has a '74 Duster 318 and is considering putting a set of (used) BF Goodrich T/A radials on...I was under the impression that suspension changes needed to be made to use radials on a chassis set up for bias tires. True or false?
 
It use to be that you had to keep radial tires on the same side and just rotate the tires front to back. I don't know if that is still valid.
 
If (and this is very unlikely) the car is aligned to the old bias ply specs, it would be to your benefit to get a modern alignment to take greater advantage of what a modern radial offers.

But that's it.
 
Only thing to watch out for is the age of the used tires. Check the DOT date on the tires. You don't want to put on 10 year old tires.
 
Alignment specs are specific to the vehicle, not the tire. It is the geometry of the wheel. Bias and radial have no different specs, but they certainly did handle different. I remember mixing bias and radials and what a wild ride that turned out to be.
 
Hahaha! I just had to drive a 61 Corvette with bias ply tires. What a treat that was. Perfectly aligned, yet the tires squealed on every turn. I had to brake moderately and the tires slid and started howling. Scared the crap out of me and the car in front of me!
 
You should definately change alignment because the car will drive much better with radials and a good new alignment, the old specs were for bias tires, That car may drive like a new one once you have a good alignment with radials.
 
Mopar to ya said:
Alignment specs are specific to the vehicle, not the tire. It is the geometry of the wheel. Bias and radial have no different specs, but they certainly did handle different. I remember mixing bias and radials and what a wild ride that turned out to be.
Click to expand...


We have countless threads that disagree with your Alignment spec statement.
 
Just had mine done after putting all new bushings up front had alot of castor added, it drives like a diffrent car now Im saying the old alignment wont wear your tires but you can definally make them drive better.
 
Mopar to ya said:
All the threads in the world makes no difference. Alignment is geometry of the wheel. Not the tire. You can't change the laws of physics, unless your name is Scotty and you work on the Enterprise.
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Sorry to argue but no, you are over simplifying things. This isn't a one size fits all world.

An alignment is a suspension tuning tool. Sure, you could simply align to a 60s spec designed for bias ply tires or you can pay the same amount of money and have the alignment done to take advantage of modern tires and driving style.

I don't care what you choose.

http://www.allpar.com/history/mopar/front-end-alignment.html
 
You simply do not align tires, you align the car. I can't make it any simpler than that. You can choose your specs for factory, or change them to tune your suspension for various things. The tires are not aligned. The car is. This thread is about questioning the need to change suspension to use radial tires. No, you do not.
 
Mopar to ya said:
You simply do not align tires, you align the car. I can't make it any simpler than that. You can choose your specs for factory, or change them to tune your suspension for various things. The tires are not aligned. The car is. This thread is about questioning the need to change suspension to use radial tires. No, you do not.
Click to expand...

And that takes me back to my first post in this thread, which apparently, you didn't read.

"If (and this is very unlikely) the car is aligned to the old bias ply specs, it would be to your benefit to get a modern alignment to take greater advantage of what a modern radial offers."

A change in suspension settings is a change in the suspension.


My guess is that you are only posting to be argumentative. Something I don't have time for.
 
1968FormulaS340 said:
Sorry to argue but no, you are over simplifying things. This isn't a one size fits all world.

An alignment is a suspension tuning tool. Sure, you could simply align to a 60s spec designed for bias ply tires or you can pay the same amount of money and have the alignment done to take advantage of modern tires and driving style.

I don't care what you choose.

http://www.allpar.com/history/mopar/front-end-alignment.html
Click to expand...

Damn it...went to all the trouble to find the same link as above. I know there is more than one thread, with input form some very knowledgeable folks, about the use of different alignment specs in regards to dinosaur (bias) & modern day (radial) rubber....
 
alignment specs in the 1960's were designed to allow the car to take advantage of the characteristic of BIAS PLY TIRES

modern radial tires have greater performance ability's and require different alignment specs in order for the car to utilize the improved ability's of the radial tires

if you put radial tires on your car and align it to bias ply specs,
you are an idiot, it is as simple as that
 
Mopar to ya said:
You simply do not align tires, you align the car. I can't make it any simpler than that. You can choose your specs for factory, or change them to tune your suspension for various things. The tires are not aligned. The car is. This thread is about questioning the need to change suspension to use radial tires. No, you do not.
Click to expand...

I can give you a perfect example. Try to unlock your mind when you read this, it is fact.

Radial tires hold their contact patch against the ground through a longer "arc of travel" than bias ply tires do. That means that a radial tire's tread will stay on the road through more of a camber arc (through a turn) than a bias ply tire.

What that means is, in order to get a radial tire's tread "in the same place" with camber is that the radial tire will require more camber, be it positive or negative because it's tread holds the ground better.

I cannot tell you the number of seminars I have attended through the years as an alignment tech that pointed this out. While you are correct that the machine heads attach to the wheels, a radial tire does require different camber settings than a bias ply tire. They also require different toe settings for the same reasons. I was beginning in the industry when bias ply tires were being phased out and radials were replacing them. This was a well known rule industry wide. Any alignment tech whose been at it a long time will tell you the same thing.

Do some reading on the differences of radials compared to bias plys. You will see the differences. They do require different camber settings.
 
caferacerx said:
alignment specs in the 1960's were designed to allow the car to take advantage of the characteristic of BIAS PLY TIRES

modern radial tires have greater performance ability's and require different alignment specs in order for the car to utilize the improved ability's of the radial tires

if you put radial tires on your car and align it to bias ply specs,
you are an idiot, it is as simple as that
Click to expand...

Uninformed or maybe too young to know perhaps, but not an idiot. no need for name calling. That was kinda harsh.
 
1968FormulaS340 said:
Sorry to argue but no, you are over simplifying things. This isn't a one size fits all world.

An alignment is a suspension tuning tool. Sure, you could simply align to a 60s spec designed for bias ply tires or you can pay the same amount of money and have the alignment done to take advantage of modern tires and driving style.

I don't care what you choose.

http://www.allpar.com/history/mopar/front-end-alignment.html
Click to expand...


Always have liked Rick. He could make a retard understand something.
 
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