Nord-Lock locking nuts - anti-vibe fix

Nyloc nuts work well if heat isn't an issue, the only thing is they do wear out after repeated use and should be replaced after a couple of removals.

Never use actual lock nuts, the crimps on the nut are meant to cut into the threads of whatever they're attached to and stay tightened permanently. A lock nut will destroy the threads of whatever bolt or stud they're attached to.

The cam lock nuts are a good idea but getting something like that to work on small 6mm studs is highly unlikely.

If the engine is mounted properly, and I mean properly all is needed is, if you're worried about looseness, is double lock nuts or self locking nylon nuts. I change out ALL studs to a grade 8.8 (US grade 5), use lock tite and have never had a broken stud, stripped hole, or even a nut that needed re torquing. Also proper torque and a cheap mod here and there helps. All this out of 5 builds. OH and I use nylon locking nuts on the rag joint also. I also don't use a nylon lock nut but once. I buy them by a box of 100 for around 6 bucks.