Hot Rod Forum banner

Rear Leaf spring questions

2K views 2 replies 3 participants last post by  kso 
#1 ·
Rear Leaf spring questions

Q: Why is rear leaf spring Datum Line higher at the rear of leaf spring or same height as front?
Q: Should the front leaf spring eye be on the same center line as the rear end at ride height?
Q: Why is the rear axle mounted closer to front of spring and center of springs on others?
Q: Leaf springs non- parallel being closer in front than rear.

I my case I’m looking for information regarding the 36 ford truck picture I use in my post.
It’s tough I consider it a Restomod not a monster truck or a rock crawler but more like a 1 ton hot rod.
So most of the Forum and information I read don’t fall as close to center for my build as I would hope.

A lot of people in these forums can design and build most anything if they know why something is done the way it is.
I think a lot of members or browser here would like to know why there doing things a certain way enabling them to make better choices for their personal build.

So if anyone could answer one or all the questions not in terms of off road applications but general car or truck applications.
 
See less See more
#2 ·
axle position.

It's been over 50 years since my Suspension classes. If I remember right the off set axle mount was to give a progressive spring rate and to minimize harmonic "POGO STICK" bounce tendencies . also mounting locations of the spring ends was for ground clearance-body design. and the lengths of secondary spring leafs, non symetrical lengths for progressive and harmonic controll.
 
#3 ·
I can answer why rr leafs are lower at the front than the rear (besides packaging reasons)...when the body leans during a corner there results a slight steering effect that enhances stability. It's not much but becomes important at higher speeds, essentially in a corner body roll steers the axle into the corner reducing the angle difference between the front and rr wheels, i.e. any sudden bump or such will cause the steered angle difference between the front and rear wheels to reduce slightly and the vehicle won't be darting around so much.

Compare to a vehicle that steers more when you lean it...a skateboard...which of-course is controlled that way but then the natural tendency is to oscillate or wobble back-and-forth at high speed unless the "suspension" is tied down very tightly.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top