Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - 4-link suspension design
View Single Post
  #11 (permalink)  
Old 03-11-2004, 04:07 AM
BillyShope's Avatar
BillyShope BillyShope is offline
Philippines Cowboy
 

Last journal entry: THE TRACTION DYNO
Last photo:
Join Date: Jan 2004
Location: Orlando, FL
Age: 78
Posts: 862
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I thought you had fabbed your links, Bullet. Didn't realize they were a kit. Anyway, if, in side view, your upper and lower links are parallel, both to each other and to the ground, the car will squat miserably on acceleration. This is because that which is called the "instant center" is at infinity.

To determine the location of the instant center (IC), visualize lines through the upper and lower links in the side view. Their intersection point is at the IC. Now, visualize a line passing through the rear tire patch and the intersection of two more lines, one a vertical line through the front tire patch and the other a horizontal line through the center of gravity. If the IC is on this line (the one passing through the rear tire patch), The car will neither squat nor rise. If below, it will squat; above, it will rise.

In accomplishing this, you don't need to worry about suspension link bind. That's why your upper links are triangulated in the kit. When this is done, it's the same as if those two upper links were replaced with a single link at the center (and, of course, a Panhard to locate the axle laterally). And, there's definitely no binding with a 3link, which is why the roundy-round boys like them.

If you're going to use bags in the rear, I would definitely recommend a no squat/no rise setup, as the low rate of the bags will accentuate the squat.
Reply With Quote