Some NASA racing classes mandate you use certain stock OEM parts on your racecar. Any solid racing mechanic can tell you not all stock parts are created equal. The trick is to use the best stock parts to make your racecar legal and as fast and efficient as possible. To do this, you want to do something called “parts-bin tuning.”
I learned the fine art of parts-bin tuning back in the old Cub Scout days racing in the prestigious Pinewood Derby. If you wanted to legally win the Pinewood Derby, you needed to purchase about 10 Pinewood kits. Sifting through all of the different wheels, you would find some wheels were junk. Some wheels were perfectly round while others had impurities from the molding process, making them not as round and thus not as fast. Putting together the best four wheels out of 10 kits could ensure a victory in the gravity-powered downhill race. How much difference does this process make? Well, the proof is in our trophy case: This method earned my son a district championship.
We decided to use this same method for finding the best stock fuel injectors. In NASA’s Honda Challenge 4 class, rules specifically prohibit the upgrading of fuel injectors from non-OEM parts. Instead of just resting on our laurels and driving a car with four stock fuel injectors of unknown performance, we decided to inspect our injectors, flow test them, and then use the parts-bin tuning method to install four high-performing matching injectors.
Our first step was to go to NASA racer AJ Gracy’s shop, Performance In-Frame Tuning, in Napa, Calif. AJ owns a cool device that lets you test injectors, see their spray pattern, and verify their output. He also can clean injectors to improve their performance. We ripped the injectors out of our Acura Integra and put them on his machine to see where our baseline was.
We saw some concerning data. The spray pattern on one injector didn’t look healthy while another injector wasn’t pushing as much fuel as the rest of its teammates. This creates a bad situation where one cylinder could be running lean, causing less performance, over-heating issues, and possible damage to the engine block.
This sent us to our local Pick-Your-Part to grab as many stock OEM fuel injectors out of Acura Integras as we could find and then start the process of parts-bin tuning to get the best-matched four injectors possible. If you are a dedicated wrecking yard nerd, like myself, a nice inexpensive toolkit with a carrying case is a must have. Never head to the wrecking yard with only the two wrenches you “think” are all you need to remove a fuel rail. Inevitably, you will need another tool. Bringing a small basic tool kit is a life saver. I never leave home without it.
After our little scavenger hunt, we checked each injector with a volt meter to ensure it was the correct one for an Acura Integra. You never really know what you will get at a wrecking yard. After determining the injectors we mined were correct, we were back to the flow test to match four good injectors. AJ cleaned the injectors, put them on his machine, and after a few different tests, and some swapping around, we found four matching injectors.
We replaced all of the seals with brand new rubber and slapped our matched set of injectors into our Honda B18A1 engine. We put the Integra on AJ’s chassis dyno to measure our improvements. The good news is we made more power and we were able to do it legally and inexpensively, a win-win in our book. More power from a few parts from a wrecking yard? How can you beat that?
To read more from Rob Krider, or to contact him, go to www.robkrider.com.