No +-40 is pretty darn good. I don't think most Tachs are that accurate to really give +-40. I would be happy if it was +-100. If it bounces 40-41-40-41 I would say its pretty close.

The next test is the ear test. Thi si shte one that is a gut feeling and guys that have run them a long time know. Does it sound hollow or detonate when at any point as its throttling up. If it does....then its a smidgen and I mean a smidgen lean on the regulator.

If the engine is just increasing RPMs and the only thing owling is the prop noise then you are golden.

Troy Newman
Team YS Performance