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Old 02-18-2010, 04:55 PM
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Derek69SS Derek69SS is offline
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Location: Mantorville, MN
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Default Tall Spindles / Tall Balljoints explained

If you want to improve the handling of your Chevelle, you must first understand what is wrong with the original geometry. From the factory, these cars were designed to understeer. To make them do this, they used a very short spindle with the upper A-arm at a steep downward angle, which results in a backward camber curve making the tires lean out of a turn, using only the edges of the tire. Not only is this bad for mechanical grip, it's also why every stock Chevelle wears the outside edges of the front tires.

Below is a diagram of the stock geometry at rest, and then in a hard turn.


*click here if picture does not show up: http://www.chevelleforum.net/picture...&pictureid=132

Notice the severe angle of the tires. All of the cornering forces are placed on a very small area of the tire

To deal with this problem, there are several things that will help. Simply lowering the car will help to some extent, but not nearly enough to correct the whole problem. Bigger sway-bars will reduce the amount of bad camber gain, but again, it's not enough... it's like a band-aid on a gunshot wound.

To fix the bad geometry, you need a taller effective spindle height. The "effective height" of a spindle is from the pivot center of the upper balljoint to the pivot center of the lower balljoint. Tall spindles with stock balljoints, or stock spindles with extended balljoint studs will both achieve this goal.

Below is a diagram of the same car equipped with a taller effective spindle height.


*click here if picture does not show up: http://www.chevelleforum.net/picture...&pictureid=131

Notice that the tires remain near vertical using the entire tread evenly across its contact patch. This is key to getting the most grip, and life out of your tires.
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Derek Kiefer, member of Minnesota's Northstar Chevelle Club
69 Malibu Pro-Touring - 69 SS396 3spd - 23 Model T roadster pickup

Last edited by Derek69SS; 02-20-2010 at 06:32 PM.
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