Check all your wiring to detect...
Check all your wiring to detect worn or frayed wires. Where the wires pass through the firewall or other partitions are areas of concern. Replace the rubber grommets and wiring if necessary to feel comfortable that a short will not ruin a good night of racing.
Crush Panels and Overall Cockpit Sealing The driver's compartment should be isolated from the engine heat, the exhaust fumes, and fire (should the engine or fuel cell catch fire). The panels that mate to the fenders, floor, and rear deck are supposed to be sealed.
Recheck these seams and reseal if necessary. Replace bent or otherwise damaged panels. Now would be the time to add heat barrier material to the panels near the driver to reduce transient heat from the exhaust passing through to the driver.
Rear End The rear end should be removed, and all mounts cleaned and inspected. Replace all grease seals, axle bearings, and pinion bearings where necessary. Check the axle tubes for damage and to see if they are straight. Shock brackets and trailing arm brackets need to be inspected for damage or wear. All Heims should be examined and replaced if worn excessively. Don't forget to look at the third link, or lift arm, too.
Look over the Panhard bar mounting brackets to see if they are bent or cracked. These mounts take a beating, especially when small hits are experienced during a race. Not much attention is given after the race, but we can all remember incidental contact that might have caused some damage.
When replacing the fenders,...
When replacing the fenders, reseal the panels that isolate the driver from heat, carbon monoxide, and fire.
Fuel Cell After removing the fuel cell, inspect the container for rust or damage that may compromise the cell itself. The fill tube assembly and foam should be removed from the cell. Clean the inside of the cell and get rid of dirt or other foreign material.
The foam should be replaced, and the fuel pickup should be inspected and cleaned. If you have a fuel pump that pushes fuel to the engine, as some cars do, inspect the wiring and general condition of the pump.
Fuel cells have a certain life span. Some newer fuels have been known to eat at the seams under certain conditions. Inspect your cell to make sure this is not a problem. (More information on fuel cell maintenance can be found in the article entitled "Alcohol Maintenance," Feb. '07 Circle Track.)
Rollcage If the body has been removed, the rollcage can be easily inspected. Look closely at all the welds. If the car is older, inspect the inside of the tubing for corrosion, which would weaken them.
If the car is unfamiliar to you, checking the wall thickness of the tubing would be a wise idea. Some racers get carried away with weight issues and might circumvent rules that require a minimum wall thickness for rollbar material. If you find weak or thin tubing, replace it. To not do so may be considered criminal in some courtrooms.
Fender braces and other connectors...
Fender braces and other connectors should be replaced. These cheap units are usually bent and abused during the season.
Body Mounts and "Glass" The overall condition of the car's body can be evaluated during this process. Any panels, fenders, rivets, or body mounts that might have been damaged throughout the year can now be replaced. Those who race hard will have some damage to the body parts. Parts made of fiberglass will be weaker as a result. New parts offer more resistance to being "leaned on" in the coming season. Also, loose body parts can ruin your aerodynamic advantage.
If you decide to replace the whole body or parts thereof, take advantage of newer designs of nose pieces, fenders, or hoods. When replacing any of these parts, check to see if a more aerodynamic piece has been developed. Don't settle for last year's design.
The key points to remember are as follows: find any structural or mechanical problems with the chassis or components that are bolted onto the chassis; correct any safety-related problems that involve wear or age of the seatbelts, restraints, fire-suppression system, helmet or seat; and make sure the driver's compartment is sealed properly against heat, carbon dioxide, and fire intrusion.
After each season, go over your race car during the winter months so that when you hit the track again in the spring, it will be just like a new car. You can avoid failures that may have dire consequences if you do this job the right way. And anyway, getting there is more than half the fun.
 This panel in the rear of...  This panel in the rear of the car was cut to fit around a piece of tubing. The cut was too large to fit closely and was never filled in. If the fuel cell were to burst, this is where fuel could possibly enter the driver's compartment. It doesn't take much to cause a lot of problems. |  Go through the rearend and...  Go through the rearend and replace bearings, seals, locker spring, and so on. Some differentials are more high-maintenance than others. This kind of maintenance should be done more than once a year. |  Inspect all the rollbar joints...  Inspect all the rollbar joints for broken welds or other types of fatigue. Pay close attention to where the rollbars attach to the framerails and where trailing arms and rear shocks are connected. |