Rev limiter story.
Back in the 70s, a good engine builder friend was into 1/4 mile boat racing, and had a blown alcohol hydro with a 504 cu. in. Arias Chevrolet motor. They decided to go with a newer better engine, so the old one sat in the shop waiting to be sold.
Tractor/4WD pulls were just becoming extremely popular, and he also built the engine for one of the top 4WD pickup pullers that was running a cast iron 454 in a Chevy pickup. They decided to "partner up" for an upcoming pull, and dropped the Arias under the hood, de-tuned it a bit, filled it with methanol, and took it to the fairgrounds. Wifey and I went along with them.
When he first warmed it up in the pits, it caught everyone's eye. No one had used this type of motor yet, much less running on alcohol. He pulled it out on the track, backed up to the sled, and started the pull. In the beginning he just barely cracked the butterflies and the pull started. When the weight got about halfway to the front, it started to bog just a bit, and he rocked his foot into it. Unfortunately, he wasn't used to all that extra power. And, unbeknownst to the engine builder, he had connected the rev limiter. The butterflies opened, the RPMs went up, hit the limiter, it killed the motor, then lit it back up when the RPM dropped. Unfortunately, the whole time there was no spark, the 14-71 Mooneyham blower was pumping alcohol and air into the cylinders. Add spark and KA-BOOM!!!
One spectator in the stands was hit by a piece of the aluminum block. Fortunately, not seriously hurt. When we got back to the pits, if you looked inside the front fenderwell, you could see people walking on the other side thru the block. Two rods had broke, and literally sawed their way out of the engine.
That was over 40 years ago, and I'm sure rev limiters are more sophisticated now, but the use of that particular one proved costly.