At the last race I attended I started my car in the paddock and drove it to the grid, shut it off, went to restart it and the fuel pump didn’t run. The relay had gone bad just that fast with no warning.

Relays are used in production cars because it is not practical to run wires to the dash through large switches to carry the current necessary to run things like lights windshield wipers etc. and auto makers want the dashboards to be pretty, small, low current switches and push button controls. We are not driving your grandma’s Escort to bingo. We also have plenty of room under our dash for a switch large enough to carry the 1 or 2 amps our fuel pumps require. (That’s a guess based on the size of the wires that are attached to the pump).

I have read here and seen several times at the track where people have had issues with untimely failure of the fuel pump relay and started to wonder why we just don’t get rid of them.

I am sure I could go the radio shack or an auto parts store and buy a dpst switch rated at 15Volts and 10 amps that would fit behind the dash. Then replace the current ignition switch. On one side of the new switch wire it as the old one is currently. On the other side of the dp, switch run a wire from the harness on the power input side of the fuel pump relay up through a new heavy duty switch and back down to the harness to the power out side of the relay back to the fuel pump and throw the relay in the trash! Now when I turn on the ignition switch the fuel pump will come on just as it does now and we will never hear about problems with those pesky unnecessary and unreliable fuel pump relays again. If you are concerned with the switch failing, pig tail all the wires and wire a second switch in parallel. If one switch fails shut it off and turn on the back up and away you go. Then replace the bad switch. Still much cheaper than those relays!

I see race cars all the time that have switches on the dash to turn on the fuel pump. Those relays are a weak link that can be cheaply and easily eliminated. Is there something wrong with my thinking?

PS I owe a public thanks to the guys from Alliance Autosport for running back to their trailer, getting a new relay and getting me on back on the track only a few laps down. Not the kind of service a guy sitting at the back of the grid in a Major race expects. You guys are awesome!

This is a spec class Properly securing the relays will minimize the risk of failure (e.g. bouncing around loosely against the bottom of the car.) Every part is subject to failure and building in redundancy and additional workarounds in a spec class can get out of hand quickly. Major issues, like fuel pump failures, have been taken care of in the course of time without the need for "one-off" fixes.

Also, in this case, the relay is what the ECU is using to control the fuel pump. Which is why the pump shuts off after a few seconds after you turn on the ignition. More importantly, shuts it off if the engine stops running.

Thanks for the explanation Dave. I was not aware of that relationship.

EVERY Spec Racer is considered a member of the group. It doesn't matter where on the grid you sit if you are important or not. The CSR's are involved in this class to help you race. Glad to hear they were able to get you on track.