Do I need a rear sway bar?

[69496]

Ok I have the ATS spindles 675lb and 175lb springs front and rear and varishock single adjstable shocks. I have a 15/16 or a 1 1/14 front sway bar available. The car is a 69 Chevelle and has a big block with aluminum heads. I want the car to handle as well as reasonably possible. I am a novice with both driving performance cars as well as setting them up so any help would be appreciated. My questions are...


Will one of the front sway bars I have work or should I buy something inbetween?
Do I need a rear sway bar?
What will a rear sway bar do for me?

[John Wright]

With a BBC up front and being that chevelle is a fairly large car...I would use the larger of the two front bars that you listed, and look into an adjustable rear bar so you can tune it to your driving style, see...if it is pushing you can add some rate to the rear bar, if it is too loose for you, then you can take some rate out of the rear bar.

[BMR Tech]

John pretty much explained your answer in a nutshell and I agree, use the bigger bar. We use a 1.25" front bar and a 1" rear bar for our A-body applications. These sizes were determined using a test car equipped with an all-iron small block w/air and the car was pretty neutral (minimum oversteer or understeer). A big block with aluminum heads weighs about the same as an all-iron small block with air so you should be fine using your 1.25" bar.

Our current 1" rear bar is an OE design that bolts to the control arms. With our swaybars and springs, AFCO shocks, and ATS spindles we were able to pull close to a G at the Super Chevy Handling Challenge and turn quicker lap times than the C5 Corvette bench mark car. While the rear swaybar rate has been matched to our front bar and will work really well for the majority of applications we realize that there are various vehicle combinations and driving styles that necessitate a variable rate bar. For this reason, we are in the process of developing an adjustable rear bar with frame mounted end links. This design works more efficiently and doesn't allow body separation like the OE design does....

[68Formula]

A lot of factors are involved. I'd follow the advice above about using the larger front sway bar. Then try running the car without it to determine if the rear would be necessary before you purchase.