Reconfiguring a novelty ignition system requires a novel solution

HackMech 1960 Buick LeSabre

Oscar Zamora writes: I own a 1960 Buick LeSabre, which was the last year of the “pedal-start” ignition system on Buicks. I just had a shop install a Holley “Sniper” two-barrel electronic fuel-injection carb on the 364 nailhead V-8. The old vacuum-operated pedal-start switch was integrated into the housing of the old two-barrel carb, which was removed. The problem is this: After the car has been started and is in park or neutral and the accelerator is stepped on, the starter engages. Otherwise, the car runs fine in drive, low, or reverse. Any thoughts on remedies?

For those who don’t know, the very cool pedal-start feature let you do a hands-free start of the car by simply pressing the accelerator. It used a switch on the carburetor that made contact when the throttle was rotated about halfway open, and it had a ball inside the switch that was pulled out of the way by engine vacuum so that once the engine was running, contact was broken. But if the carburetor has been replaced, either the linkage-vacuum switch will need to be adapted to the new carburetor, or something new will need to be rigged up, or it will need to be replaced with a conventional ignition switch. If you want to keep the pedal start, I’d imagine it’s not hard to put a microswitch on the linkage that closes when the throttle is partially open and also triggers a relay to the starter. The trickier part, as you’ve encountered, is the bypass to prevent the starter from engaging once the engine is running. You need to find a vacuum-actuated switch that’s normally closed, opens (shuts off) in the presence of vacuum, and is adjustable so you can dial it in. Just wire it in series with the voltage to the relay to the starter. Or you can use one of the programmable outputs of the Holley Sniper carb and create a voltage that’s present only on very low rpm (while the starter is cranking the engine) but shuts off on idle or above. You’d then use this to trigger a gating relay that enables or prevents the voltage from the switch on the linkage from reaching the starter.

John Norman writes: What’s your opinion on cutting springs?

First and foremost, once the springs are cut, you can’t go back. If the car is original in most other ways, it is nice to keep the stock springs somewhere in a box. But I’m a practical guy, and if cutting a coil off a set of springs will bring the ride height down to where it’s visually appealing, and if that’s a better option than buying a set of lowering springs for the car, either due to high cost or lack of availability, I don’t see the harm. An important note, though, is that springs can have pigtail, square, or tangential ends. Those ends need to mate with the perches in which they sit, so you shouldn’t cut pigtails or square-ended springs, only tangential-ended ones. Cut one coil at a time with an angle grinder or a metal-cutting saw—not a torch, as this can weaken the steel. Wear eye protection, and don’t try to emulate some of the cable shows and cut them while they’re still on the car; remove them first. Be aware that although cutting springs increases the spring rate (makes them stiffer), it also reduces the total compressible distance. Cut too many coils and you can cause coil binding over bumps. In short, make small changes, then test.

Read next Up next: Piston Slap: Finding fuel in a thirsty Toyota

Leave a Reply

Your email address will not be published. Required fields are marked *