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Again, consideration of using a rear sway bar will factor into deciding the springs to get. In general I'd say go softer then add sway bar sizing to dial things in or you could go heavier and not use a bar at all. For a ball park guess, I'd say 160# if using a rear sway bar, or 200# with no bar.




Sorry. I guess I buried this in the middle of too long a response earlier.

The Alltime guys definetly know their stuff, but they do tend to be pricey.

The SS springs may not have "a lot" of arch but the point is for a handling application, the spring should be flat. Even the old DC and MP manuals say flat is mandatory for maximum cornering effort. While you can use hangers and shackles to get a SS spring to a decent ride height, it still has some arch to it which can create a lever arm against the mounting points. A flat spring reduces this leverage. Think of it this way, breaker bars are longer than ratchets to give you more leverage for breaking loose those stubborns bolts. Side loading a leaf spring with arch would work the same way.

Speaking of which, adjustable front hangers are a great way to get two inch drop from a mounting point. Another is to replace shackles with sliders. A slider is a u shapped frame with horizontal slots running down the sides. A bearing runs in two track the length of the slots on each side. The rear of the leaf spring is bolted in between these two bearings. Instead of pivoting like a shackle, the leaf slides back and forth on the bearings. This is a 2" drop in mounting point over a shackle. I've only ever used these in copetitin, so I can't say how they would work in a street application.

Another advantage to solid or bushing mounted leaf spring is the width of the spring resists twisting as well which helps increase roll resistence compared to a coil spring.

However, as mentioned in an earlier post, if you simply want to use a leaf spring as a spring and not the whole suspension locating system, you can swap out the front bushing for a spring eye pivot. This allows the spring to twist and roll with the car and not resist twisting. Once it has this freedom of movement, sway bars and panhard bar/watts link become a requirement to locate the suspension and provide roll resistence. The advantage of doing this in a track application is that the rear roll center location can be easily changed with just minor adjustments. This can have a tremendous impact on how a car will hook up exiting a corner. It also allows you to run a lower spring rate since the leaf now acts exclusively as a spring and not a roll resistor. FYI, this is how the trans am cars of 1970 were set up and they continue to use this set up in vintage racing to this day.

As an aside to drag racing with a handling set up; yes, you reduce the effeciency of weight transfer and suspension movement, and consequently, will increase you e.t. over a similarly powered car built exclusively for straight line performance. However, a handling set up will be less sensitive to track, tire, and atmospheric changes and will be deadly consistent in later rounds where cooling things down in an effort to maintain consistency becomes a factor. Not to mention that turn on the return road is a lot less scary.