I've been pondering the question of wheel rates on my Merlyn Mk6a sports
racer, which is essentially a Merlyn F2/F3/ FFord type chassis that happens
to seat two people. What I've got is a bad oversteer problem that I can't
tune out with bars or camber type adjustments, so I plan to go with stiffer
front springs to attempt to get a better balance in the car. I also have a
bit too much roll, which is why I'm tending towards stiffening the front
rather than softening the back.
So, I've been reading the threads in FFord 101 over on the FFord
Underground site, and some very experienced guys there say to start with
wheel rates about equal to corner weight and go up from there, to as much
as twice corner weight. Given a corner weight of about 225#, and a 2:1
motion ratio, getting a 225# wheel rate would have me putting about 900#
springs on my Merlyn, which is a bit stiff since it has 200# springs
now. But these guys are serious that they run those sorts of rates on
their modern cars.
So, if it's not too presumptuous of me, what kind of wheel rates are people
using on their vintage formula cars, especially guys using Dunlop FFord
spec tires? Any logic to the choice, or is it what the previous owner put
on the car?
TIA, Brian
Wheel rate = spring rate / Motion Ratio^2, BTW, so 225# = 900# /
2^2. I'm pretty sure that's the correct formula. Motion Ratio is wheel
travel / shock travel.
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