Originally posted by B4
Wouldn't having LSN richer mean that more pre-tension was required so the the engine would be able to build revs before clutch engagement.
Yup. That's what I thought too.
The way I interpret is like this... When your bottom end LSN is lean, then you have plenty of bottom end power. When the clutch engages, it does not bog down the low end and because of the good launch on the low end (because of it being lean), you may set the pre-tension nut loose.
When you set the LSN rich, the engine may seem to bog down when the clutch engages. Seemingly not enough power or RPM to pull the car in first gear.