• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Radial vs. Bias Ply

mvent

Well-Known Member
Local time
2:35 AM
Joined
Nov 13, 2009
Messages
133
Reaction score
47
Location
usa
Need to replace my 215-70-15 radial B.F. Goodrich Silvertown red lines on Magnum wheels. Really like the look of the bias ply tire but I'm concerned of what I'd be giving up in terms of ride and smoothness. Been a long time since I drove a car with bias ply tires. Never seem to get a good balance job with these Goodrich tires, even when they were new in 2006. All feedback and suggestions appreciated.
 
I put radials on my ‘68 Satellite daily. It was day and night. The car felt like it had a rebuilt suspension.
 
I found that bias ply tires nibble at every imperfection in the road. Driving was not a pleasure. I have radials on both cars and they drive/handle much better.
 
I hope these are not the same tires that were installed in 2006 ! Driving on 16 year old tires is rolling the dice on needing fender/body work.
Proper wheel balancing requires weights to be added wherever they are needed to both statically and dynamically balance the tire/wheel assembly.
Many people try to "hide the weights" on the rear of the rims.
Look at a real race cars wheels. Weights on the outside and even duct tape over them on Indy type alloy wheels.
Balance problems are usually caused by excessive wheel runout or improper balance. Very little training done today.
Tires must be match mounted and if the machine calls for anymore than 1 1/2oz. at any point on the rim, try rotating the tire 90 ° and try again.
The lowest quality tires made today are generations better than the highest quality of 20 years ago.
Bias ply tires had an average life of 20-25K miles. Bias belted 30-35K. The original radials were rated for 40K. A lot for the times.
Now 40 k is a low mileage tire. This is of course for standard passenger tires, not soft compound high performance tires.
Radials are much smoother, higher traction, safer tires than any bias ply. There are several reasons that the bias ply tire is a thing of the past, just like front drum brakes and carberators...
 
I hope these are not the same tires that were installed in 2006 ! Driving on 16 year old tires is rolling the dice on needing fender/body work.
Proper wheel balancing requires weights to be added wherever they are needed to both statically and dynamically balance the tire/wheel assembly.
Many people try to "hide the weights" on the rear of the rims.
Look at a real race cars wheels. Weights on the outside and even duct tape over them on Indy type alloy wheels.
Balance problems are usually caused by excessive wheel runout or improper balance. Very little training done today.
Tires must be match mounted and if the machine calls for anymore than 1 1/2oz. at any point on the rim, try rotating the tire 90 ° and try again.
The lowest quality tires made today are generations better than the highest quality of 20 years ago.
Bias ply tires had an average life of 20-25K miles. Bias belted 30-35K. The original radials were rated for 40K. A lot for the times.
Now 40 k is a low mileage tire. This is of course for standard passenger tires, not soft compound high performance tires.
Radials are much smoother, higher traction, safer tires than any bias ply. There are several reasons that the bias ply tire is a thing of the past, just like front drum brakes and carberators...
Trying to find someone to use a Road Force balancer correctly is tough. We had one of the Hunters when they first came out Bitchen machine. Along with their hi-zoot tire changer it made match mounting a breeze.
 
On the street? Radial. Especially today's tire technologies. On the strip with slicks? Bias. I tried a set of radial slicks on my 10 sec Duster. Ran same times. But did spin them once that was unexpected. I believe they don't flex as well. I was told they last longer, but I wanted them off.

I'm sure others have had different results. But just my experience.
 
In my humble opinion.....
If you have a hemi car or a Sixpack car, restored, it needs bias redlines, (and they should be goodyears, and Goodyear only). If not, get the redlines you want. I would get the radials.
There have been several stories here about the poor quality of the repop redlines, both bias and radial.
I would check with Diamondback Tires. They do lots of specialty tires, including making redlines out of drag radials. I would trust their recommendations.
 
I changed the third rate BFG T/As on this car for the much better looking Polyglas GT's. It was a Hemi car so that's how I justified it but I can tell you I will never again install belted or bias ply tires on a car that I own. Simple as that. I prefer driving them to looking at them.

hemicharger.jpg
 
I'm not sure but are poly glass a bias design ?
 
Yeah, I used to run radials on the front and bias ply on the rear. Like mentioned, non radial tires like to grab uneven pieces of the road and I hate that too but the rear didn't matter so much......and I liked the little bit of added oversteer it caused too. Most of these old cars have a ton of understeer so doing it my way worked fine. The only factory car that came close to being neutral was a 71 340 Cuda and it had a bit of oversteer with radials all around. Maybe it was because of the 275-60-15's on the back and don't really remember what the 14's were on the front.
 
I just finished driving a few hundred miles on the Goodyear bias redlines as I was taking several pictures of my car and wanted the look. Well, they do look awesome! But drive like crap. They pick up the cracks in road and that feels harsher than a radial, the don’t balance very well and seem to shake more, and they LOVE to climb out of every road crown and rut, with force! The second I put my mags and radials back on I could drive the car with ease, it ran smooth and straight, no vibrations.
= bias redlines are for the look and or shows really, or if you never get your car above 30 miles an hour and just take it to the grocery store and back. Maybe the originals were better quality than the newer re-pop ones, I don’t know. All around my vote is for radials.

Just for show! ⬇️
4D1E8AA9-92FB-459F-BCA3-7B43BE45269D.jpeg
 
The first time I experienced radials was in Germany in late 71. I bought a 66 Opel Rekord and it had them all around and man, it handled the crappy roads with ease and didn't dart all over the place.
 
In my humble opinion.....
If you have a hemi car or a Sixpack car, restored, it needs bias redlines, (and they should be goodyears, and Goodyear only). If not, get the redlines you want. I would get the radials.
There have been several stories here about the poor quality of the repop redlines, both bias and radial.
I would check with Diamondback Tires. They do lots of specialty tires, including making redlines out of drag radials. I would trust their recommendations.
Back in the day these cars did come off the factory line with the redlines. But they were crap. And most dealership's changed them to a newer (and typically wider) than the 5.5"? Today's spare donut is as good as the late 60s redlines?

I understand the "Blue blood's" wanting the factory "Look." But I don't remember any actually driving them back in the day? If the dealership didn't swap them out. Any respectable street guy did.
 
A number of the tire manufacturers make bias look radial tires. Maybe try that route?
 
I believe we are missing the point today? I was a child of the 70s. And my high school car was a 66 GTO. I would have been laughed off the parking lot had I swapped my Cragars with wider stance for redlines on steelies?

I'm not suggesting go with today's 20 inch on a wagon wheel rim. But I honestly do not believe you gain any value on the thin redlines? I run period correct rallies on my 69. Looks and performs far better. (Upgraded rims was really the only "Bling" option we had?)

 
Last edited:
Simple. Unless the car is stationary, radials absolutely. Get the size you want in a redline radial from diamondback tire.
 
Back in the day these cars did come off the factory line with the redlines. But they were crap. And most dealership's changed them to a newer (and typically wider) than the 5.5"? Today's spare donut is as good as the late 60s redlines?

I understand the "Blue blood's" wanting the factory "Look." But I don't remember any actually driving them back in the day? If the dealership didn't swap them out. Any respectable street guy did.
One of the first things I did to my first car (and many others afterwards) was swap out the 2 dollar factory shocks and do something about the stock steel wheels. Couldn't afford aftermarket wheels so the 'deluxe' hubcaps came off and baby moons when on. My car was yellow with a black vinyl top and the wheels were also black and the moons were a nice touch imo. About a year later a buddy pulled the factory road wheels off of his 69 AMX (not sure what AMC called them) and sold them to me for what I thought was a more than fair price. Looked like a nice up grade to me. Bought a pair of White's Magic 50's for the rear that had the red lines on one side and white lines on the other. Thought it looked ok with the red out.
 
One of the first things I did to my first car (and many others afterwards) was swap out the 2 dollar factory shocks and do something about the stock steel wheels. Couldn't afford aftermarket wheels so the 'deluxe' hubcaps came off and baby moons when on. My car was yellow with a black vinyl top and the wheels were also black and the moons were a nice touch imo. About a year later a buddy pulled the factory road wheels off of his 69 AMX (not sure what AMC called them) and sold them to me for what I thought was a more than fair price. Looked like a nice up grade to me. Bought a pair of White's Magic 50's for the rear that had the red lines on one side and white lines on the other. Thought it looked ok with the red out.
Yup. I remember couldn't wait to make upgrades. Now? A whole different ball game.
 
Auto Transport Service
Back
Top