The 2006 HC Official Rules have been released. Hot off the digital press here:
Honda Challenge | changes (Updated for 2006!)

Summary of 2006 Honda Challenge Rule Changes


a) Added 50lbs to certain cars in the H1 class
b) Adjusted H4 weights and added Prelude, Accord and Civic to class
c) Allowed another 50lbs of ballast
d) Allow Remote Reservoir shocks in H1 with 75lbs weight penalty
e) Allow Composite Hatch/trunk in H1
f) Disallow Canards, etc
g) H1 Restricted Prep cars get a 75 weight reduction for big brakes since we bumped base weight
h) Allow tire rod ends/bump steer kits in H1
i) Allow aftermarket control arms of identical configuration as OEM in H1
j) Allow Data Aq systems up to $1800 in H1

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