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Old 10-16-2002, 03:19 PM's Avatar is offline Moderator
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Don't know of any book w/ all the answers but there are some basic principles that must be followed. If you have parallel leaf springs, bump steer is unavoidable, but can be minimized. I have it in my stock '53 Chevy pickup. First, DON'T raise the front end by arching the springs. Keep them as mildly arched as possible. This is because when a leaf spring is compressed it gets longer. As this happens the axle is moved away (front shackles) or nearer to (rear shackles) the steering gear. If the driver is holding the steering wheel steady, the pittman arm will steer the wheels left or right causing an unexpected change of direction of the car. Old gassers crashed at the end of a run due to this phenomenon because when the parachute was deployed at 160mph the car nosed over and the car steered violently left or right and into the guard rail. Use straigh axles or riser blocks to get the height you want. On my Willys, I use a stock axle 'cause it looks great drilled and chromed but has quite a drop. Thus I added 3" riser blocks and increased the axle shackle bolts from 5/16" to 3/8" to handle the higher stress on them. I have a little bump steer but in 5 years have never had any control problems. I subconsciously accomodate it. Some gassers went to a Ford type transverse single spring (Altizer, Finders and Kibler 'Traveler' '33 Willys gasser) which gets rid of bump steer. By keeping the springs relatively flat they can be a little softer and give a better ride. Don't worry too much about camber and caster 'cause front end shops can use wedge shaped shims and axle bending to set these up. This is SOP for them. What ever you do, don't get more height by using longer spring shackles. This is not only ugly, it is dangerous because it destabilizes the whole suspension.

Other than that just pay attention to keeping things strong and avoid interference problems such as pittman arm hitting left tire in a hard left turn, or binding of brake hoses. Of course, if you use cross steering (not Gasser standard practice) instead of parallel pittman arm steering, then clearing oil pan and frame stuff is a concern.

I recommend you look at a lot of '60s rod books to get ideas of how to set it up. Try and post pictures of your project.
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