Tech Tips
Racing can be a very humbling experience for many amateurs, and most weekly racers don't have a big crew and bank account to help them maintain their race car. As fellow competitors, we sometimes like to keep our "secrets" to ourselves, treating them as the advantage they can be over a newcomer to most any Motorsport. While respecting the hard work of all racers trying to get and maintain an advantage over their competition, we always need to keep in mind the need for new blood in our sport to continue a tradition of strong competition. Getting a new racer past that first and second year of trails and tribulations until they can feel some form of accomplishment and reward for their hard work is all of our responsibilities as good stewards of our sport, and many of the tips listed are designed to serve just that purpose. Thank you in advance for any lessons-learned tips you would like to forward to us as reminders to the old guard and cheaper lessons to the newcomers.
Brakes Fluid: Brake fluid should be cycled out and renewed by bleeding the brake system during the race season. Bleeding the rear brake system is especially important has most dirt race cars use mostly rear brake with aggressive pads that build tremendous heat in the rear calipers and fluid.
Brakes: As a general rule, dirt track race cars normally use a 1" master cylinder on the front, with a 7/8" master cylinder used on the rear to generate more rear brake bias. Likewise, asphalt race cars would reverse these to make more front brake bias. Hydraulic throw-out bearings and C-T race transmissions normally use a 3/4" master cylinder. External clutch slave cylinders can sometimes have their throw maximized by using a 7/8" master cylinder while slightly requiring more pedal pressure.
Fuel System: Make sure everyone on your race team knows how the fuel filter element goes into the fuel log. The filter should always have the closed end with the spring toward the fuel cell, and the open end of the filter toward the carb. This makes sure there is minimal restriction and all the filtered debris will be on the outside of the filter for easy inspection.
Cooling System: When possible, v-belt and serpentine racing pulley kits can maximize belt wrap on the pulleys by mounting the power steering pump on a block mount as opposed to a head mount. Anything a racer can do to reduce belt slippage will maximize cooling efficiency. 1 to 1 ratio pulleys are normally recommended for maximum cooling depending on the maximum operating rpm of the engine. Serpentine kits can sometimes run slightly under-driven as they traditionally have less slippage than v-belt systems.
Tools: Maintaining a race car is time consuming, so everything you can do to minimize this time is to your advantage. Standardizing nut and bolt wrench sizes saves time and makes pit repairs quicker and easier. This can be accomplished by using nuts with smaller hex sizes. Anytime a maintenance or repair is being done regularly with a constant aggravation in performing the task, time should be set aside to determine a better procedure, a better tool (possibly a bent or welded wrench/socket), or a better combination of parts allowing the task to be performed easier.
Fuel System: When building your race car with a new or used fuel cell, always inspect the tank for debris, as well as checking the pickup tube (hose or aluminum tubing) for flaws and pickup corner location so the pickup point will end up in the correct location when mounted (normally right rear corner). Aluminum tubing can be porous and rubber hose can be deteriorated. Mounting rubber fuel line with tie wraps can restrict fuel flow if pulled too tight, Broken fill cap roll over flappers can break off, and roll over valve balls can both be sucked up against the pickup making a fuel delivery problem very hard to find.