Scrappy's new British Spring leafs dropped on me in last year's Great Race.
The replacement set also headed south. British Spring is a quality supplier,
and I couldn't figure out what the problem was.
I think I know now. The leaf ends appear to be cut with something like a
brake or shear. They are cut 'up'. This leaves a sharp edge rubbing against
the leaf above it. After only a few thousand miles the lower leaf ends had
all cut into the leafs above them, as deep as .003-.005! The friction surely
generates localized heat, and over the course of 12 hour driving days, the
main leaf began to sag right where the #2 leaf was hitting it.
The fix was simple enough. The old hot rodders used to take their Ford
springs and radius and chamfer the edges that rubbed. I did that, and added
Teflon rubbing strips, again designed for Model A Fords (same leaf width).
This allows the springs to slide easily, reducing friction and heat, plus
giving a more supple ride.
I also made a full span #2 leaf, by taking an old main leaf and cutting off
the eyelets. This gives better support to the main leaf, and with the Teflon
strip the ride is not stiffer, but capable of supporting a full load (gas,
trunk 'o spares and tools, and two up). Smoother spring action is better for
sucking up rough roads, but I'll settle for them holding their arch!
The springs come apart easily enough: remove (always the trick, except mine
have been out so often lately...), take out the center bolt, bend the clamps
back, and separate the leaves. Simply grinding down the tips and reassembly
should help. The Teflon strips are available at hot rod shops, or Ford
specialists like Bob Drake. It's under $20/roll, enough for both rear leaf
springs, and you really only need to add them to the top 3 leafs.
I also use motorcycle chain lube to keep the metal on metal leaves rust free
and supple.
Steve & Janet Hedke
1957 TR3 "Team Scrappy"
Great Race #45
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