Cactus Classic: Stock Racers Get Creative To Shave Grams and Lap Times

Stock racing has always been a very popular and competitive class, but with the rhythm section in the center of the track being so critical, racers are resorting to some very creative ways to gain an edge. Working within the rules, racers are pushing batteries, motors, drivetrains, suspension and other tweaks in order to make the treacherous double/triple. At this point, there are only a few drivers able to do the feature consistently. Local Jeff Kulp is one of them giving it a go and his milling and lightening of his transmission is just some of the things he and others are doing to gain fractions. Start by milling an already lightweight aluminum layshaft, install those ceramic bearings dry with just one drop of oil, swap the idler gear shafts for carbon fiber ones, use cut down idler gears to reduce friction, gut the slipper and go direct drive, install titanium screws…the list goes on.

But, let’s not forget about the motor.  Cherry pick a good one, run it on a dyno and test gearing, rpm, and efficiency. Make sure you set your buggy up so you don’t have to use brakes, because brakes build heat and reduces efficiency in your motor over a five minute run. Fine-tuning and testing is the rule and those off a tooth on the pinion run the risk of coming up short on the triple.

And finally the batteries; cycling the packs is important in breaking down that internal resistance and getting the chemicals active. Discharge hard and charge hard, but only if you are timing the final charge to peak as you approach the drivers’ stand. Reminds me of the old NiMH sub-c battery days. Are we really back to those days of cycling and timing charges with limited lifespan of packs? Ugh.