Products to Compare (max of 3)
Compare These Parts

Can I Mix Bias and Radial Tires?

Add Article To List
Tags: Tech

Everyone has that special voodoo that they do. From those special driving gloves, to making your significant other take off their shoes, to the fuzzy dice handed down from your grandpappy, we all have our little quirks that we think help our vehicles perform better. Sometimes you heard about it from a buddy over cards, sometimes someone at a show told you they heard it from their brothers’ sister’s third cousin twice removed. (It’s happened.) We are going to address one of those quirks right now.

What’s the big deal with mixing radial tires and bias-ply?

The main difference between radials and bias-ply tires is in the construction. Radials are built with cords basically running at right angles compared to each other when compared to the tread pattern center, and have reinforcing belts of either cording or steel. Bias-ply tires are constructed using overlapping cords placed in a crisscross pattern of 30°-40°.

Due to the respective construction, the bias ply tire will have significantly less sidewall flex than the radial. The contact patch will be less, and in result you will not be able to transfer as much power to the ground. The tire is also less flexible when mounted, which provides for the major disadvantage of a bias tire, as more feedback is transferred back to the car on rough surfaces.

Radial tires will have more sidewall flex, allowing for more efficient transfer of power to the ground. Increased efficiency in power transfer means better fuel economy. Radials also last longer than their bias-ply counterparts, and are more resistant to punctures and tears. You will also reap the major benefit of the radial tire: better steering responsiveness.

What this means is that at highway speeds, the bias-ply tire will heat up and actually lose traction. While it is not recommended that you not mix radials and bias-ply tires on the same vehicle, some do in race applications. If you so choose, be certain that the radial tires are placed on the rear axle, and the bias-plys on the front. In a race situation with bias-ply tires on the front axle you will experience under-steer. Be aware that the difference in construction will make the tires react very differently, and result in the vehicle being very unstable.

In the end, we will leave you with one last bit of advice. Tires of different sizes, constructions, and wear history can and will affect the stability and handling of your vehicle, and potentially endanger you and those around you. We say don't mix them.

Products Featured in this Article

Related Articles

Selecting The Best Performance Spark Plug Wires
by Jason Lubken - Posted in Tech
Learn about some of the differences between factory plug wires and the improvements you'll receive with a quality set of aftermarket performance wires in our spark plug wire buyer's guide
Murray Vintage Pedal Car Identification
by Speedway Tech Team - Posted in Tech
Murray Ohio Manufacturing Company started producing pedal cars in the 1930’s. Here’s a guide on identifying Murray vintage pedal cars by body styles and various features.
Garton Vintage Pedal Car Identification
For 95 years, Garton Toy Co. was the largest wheel goods toy factory in the world. Follow this guide on how to identify various Garton vintage pedal cars including the Kidillac and Tin Lizzy.
Installing ICT Billet LS Motor Mount Adapters
by Jordan Evans - Posted in Tech
Jordan shows us how to use ICT Billet motor mount adapters to bolt a 6.0 LS into his 3rd-Gen Firebird.
How to Install a Billet LS Alternator Bracket
by Jordan Evans - Posted in Tech
Follow this guide on installing a Speedway Motors Billet LS Alternator Bracket. If you’re looking for a simple solution that looks good while solving positioning issues from factory brackets, then these brackets are for you.
Gen III/IV LS Engine ID Guide
by Speedway Tech Team - Posted in Tech
Looking to swap the venerable LS engine into your hot rod, muscle car, or classic truck? Take a look at our detailed identification guide for Gen III/IV LS engines before you hit the salvage yard or swap meet!
Head and Neck Restraint Systems
by Marcus Kennedy - Posted in Tech
To prevent injury, your racing safety gear must meet the SFI 38.1 specification and fit properly. Learn how to choose a head and neck restraint system for competitive motorsports in our buyer's guide.
LS Radiator Guide
by Joe McCollough - Posted in Tech
The radiator is an important part of that LS swap. Here are some options from the Speedway Motors catalog.
Chevy Small Block - Short vs Long Water Pump
by Jason Lubken - Posted in Tech
Small block and big block Chevy engines were designed with two styles of water pumps, short and long. Before you purchase a new pump, it's important to determine which oneyou have.
Chevy Small Block Casting Numbers
by Speedway Tech Team - Posted in Tech
Decode small block Chevy engine suffix codes and block casting numbers with our SBC decoding info guide. Learn how to find and decipher your small block Chevy engine codes quickly and easily!