It’s Spring, and That Means Tune-Ups. Are You Ready?

I have three kinds of vehicles. The daily-driver Silverado, the beach-toy 1975 Bronco, and the 9.08-second 1971 Dodge Demon. The Silverado needs oil changes and, someday, spark plugs. The Bronco has a Ford Racing Z460 engine that has ported RHS heads, a sizeable roller cam, and makes 604 hp. It has a few quirks—like a hunger for neutral safety switches and, for a while, cam gears—but is a semi-reliable vehicle for donut and beach runs on the weekends. The Demon has a twin-turbo 6.4L Hemi that makes 1,050 hp. All three need routine maintenance.

If and when the Silverado needs a tune-up, it will be about gapping and threading-in some reasonably priced spark plugs and pushing a reset button. Maybe I will clean the air filter while I am at it. It’s a reusable K&N. That’s it. There is no distributor cap, rotor, carb, or anything else that requires consumable replacement parts.

The Bronco is a little more complicated. It will need a cap and rotor, a carburetor adjustment via a lean roll or similar operation that requires a vacuum gauge, tach, or better yet an 02 reader to really get right. The plugs are behind headers, of course, requiring the special 5/8 that I made with a bandsaw and a welder. There are two fuel filters, one on the frame, pre-pump, and one under the hood, plus float bowls to look at and minor leaks to address as the rowdy engine shakes things loose. The investment is about $100 and two pleasant hours in the garage.

The Demon lives up to its underworld name. When it needs maintenance, I need to be mentally prepared. This year, the 10-year-old fuel pump failed to keep up with the new engine’s power output, spiking the injector duty cycle to 200 percent. Changing the pump meant changing the actual fuel pressure in the Holley Dominator EFI by about 15 pounds to meet the combo’s VE requirement. That made the existing fuel maps completely worthless, requiring a couple of hours of base map learning. I live in Los Angeles, a place where there is a red light about every 500 yards stocked with angry people with somewhere to go. I get the horn and the finger when the car goes rich and stalls in the middle of an intersection. I won’t even mention the neighbors listening to me start and stall trying to sort out the cold-start sequence. The spark plugs are about $200 per set because there are 16. Springtime maintenance has cost me close to two weeks and $1,500 to get it right.

So spring maintenance is a hassle. So what? Would I give up any of these cars? Nope. Each has a special purpose, be it fast, fun, or reliable. One car can’t do it all, so I will drive the one that’s currently working and be happy with it.

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