Xtreme R/C Cars just did a big spring test article. Your findings (actual rates don't match advetised rates) are pretty normal. The really shocking thing is the discrepancy you can find in pairs or springs! Ray Speed and Schumacher are the only companies whos rates are correct and have closely matched pairs.
Tamiya sells kits of matched springs 49xxx, so its just a matter of waht do u want
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