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curleysracecars
01-25-2016, 09:49 PM
Hey all,
Long time lurker here. I am building a 64 Fairlane and am trying to control myself, sticking to my original plan of an above average street car. Its gotten to be a bit more, but Im trying...
Anyways, ive read alot and cant seem to find a definitive answer in regards to the leaf spring angle, or better described as the leaf spring mount heights. We know factory setups almost always have the front mount lower than the rear. In reading Puhns book, it seems he suggests having the front and rear at the same height off the ground would be ideal for handling. He uses a longer rear shackle on a Pinto as an example. He explains it as eliminating the rear roll steer which was implemented by the factories.
How true is this? I had planned on a tubular crossmember and then thought maybe it would be worth it to have an adjustable front mount...5 holes on 1" spacing. Im trying to decide if this is beneficial and also if the overall consensus is to have both front and rear mounting points equal distance from the ground.

What about the width between front mounts versus rear mounts? Any ideal inward angle you want the springs to be at?

Also while were on the topic, is it always better to run a 2.5" spring versus a 2"? Id assume spring rate is spring rate, but thought maybe the wider spring would help contain lateral movement of the housing.

Thanks in advance for the info! I know Im a newb...and I come from YB, so I can take a bashing. Flame on. :)

DBasher
01-25-2016, 10:13 PM
I have no clue....if I were you and looking for answers on how to make a ford handle I'd be reaching out to Mike Maier. Mike Maier Inc just came out with a new spring pack for mustangs, he's got a ton of knowledge on making cars handle on leaf springs.
The other guy is Ron Sutton. He's recently taken another ford and put it on composite springs with a locator and JRI shocks, he's transformed the entire feel of the car.
There is a science to springs and getting them to work as designed. If you add a panhard or watts link you are now allowing the spring to travel up and down as designed without the lateral load. That lateral load messes with the travel, spring rate and causes binding, not what the spring is supposed to be doing.
Hopefully Ron or someone with more knowledge chimes in. What I do know and have seen is you don't need fancy shmancy 3-4 link set ups to be fast.

YB still around? :D

curleysracecars
01-26-2016, 06:54 AM
Thanks for the info. I will have to look up Mike and see what he has to say.
YB is still around...not quite what it once was but.... :)