Bias Ply vs Radial

[mopar jeff]

Originally Posted by BlueOval Ralph

Anti-dive and anti-squat
Anti-dive and anti-squat are expressed in terms of percentage and refer to the front diving under braking and the rear squatting under acceleration. They can be thought of as the counterparts for braking and acceleration as jacking forces are to cornering. The main reason for the difference is due to the different design goals between front and rear suspension, whereas suspension is usually symmetrical between the left and right of the vehicle.

Anti-dive and anti-squat percentage are always calculated with respect to a vertical plane that intersects the vehicle's center of gravity. Consider anti-dive first. Locate the front instant centers of the suspension from the vehicle's side view. Draw a line from the tire contact patch through the instant center, this is the tire force vector. Now draw a line straight down from the vehicle's center of gravity. The anti-dive is the ratio between the height of where the tire force vector crosses the center of gravity plane expressed as a percentage. An anti-dive ratio of 50% would mean the force vector under braking crosses half way between the ground and the center of gravity.

Anti-squat is the counterpart to anti-dive and is for the rear suspension under acceleration.

Anti-dive and anti-squat may or may not be desirable depending on the suspension design. Independent suspension using multiple control arms can be an issue if the percentage is too high (say over 30%). A percentage of 100% in this case would indicate the suspension is taking 100% of the weight transfer under braking instead of the springs. This effectively binds the suspension and turns the independent suspension into no suspension like a go-cart. However, in the case of leaf spring rear suspension the anti-squat can often exceed 100% (meaning the rear may actually raise under acceleration) yet because there isn't a second arm to bind against and the suspension can freely move. Traction bars are often added to drag racing cars with rear leaf springs to increase the anti-squat to its maximum. This has the effect of forcing the rear of the car in the air and the tires onto the ground for better traction

Awesome explanation, and thanks for taking the time to do that. How do you come up with a measurement like "144%" though? Do you go by photos, and draw some lines on them?

[Alan Warman]

Kenny
What back spacing do you have on your new wheel's.

BlueOval
Thanks for the post there's a lot of info there.

Greg
What back spacing do you run.

Tony
I did not no Alf Weibe made a kit for the G-Body. The shocks I have now are a worn out Koni's. The adjustment does not work anymore. Thanking about Afco's.

Jeff
I drew mine out on paper. But you can go to a hobby supply store and buy poster board, and you can drew it out full scale. Also there are programs you can buy. Just plug in the numbers and it does the rest. Go to yellowbullet.com they talk about it all the time.

Thanks for all the input guy's not only did you help me. But you help Jeff also.

Here is a picture of the car at Dallas

[Dennis Paz]

Anyone have any idea how much a typical bias tire grows compared to a radial?
Alan
I am a little new at this class stuff but my ss/ma car dont care if I leave at 7000 or 5ooo with the radial it will not spin either way and will 60 the same.

[BlueOval Ralph]

I am not that smart I just Web Search - powered by Google it and thats what came up it is amazing the info on the InterNet
Ralph



Ia

Originally Posted by mopar jeff

Awesome explanation, and thanks for taking the time to do that. How do you come up with a measurement like "144%" though? Do you go by photos, and draw some lines on them?

[mopar jeff]

Originally Posted by BlueOval Ralph

I am not that smart I just Web Search - powered by Google it and thats what came up it is amazing the info on the InterNet
Ralph



Ia

Well I appreciate it either way. I will have to look into this more. Thanks.

[mopar jeff]

I looked into this a little, and it seems like it's more of a 4 link or ladder bar thing, as far as adjustability goes. With my mustang, and only being able to adjust pinion angle, it doesn't seem like this will really pertain to my car. Is that right, or am I missing something?

[Kenny Wigington]

Alan, 15 X 10 with a 5"BS.

[Caperat]

The radial needs to be used on a track that has excellent hook. If you break loose, the radial won't recover like a bias ply will.

[Chipper Chapman]

I found the radials on the camaro dead consistent Kev, we weren't making big power but 18-20 pounds and would hook on snot, the same every pass.