valve overlap

[Gwyn Reedy]

I'm curious (not being picky). Going by the apparent meaning of the phrase
'lobe separation', wouldn't greater lobe separation mean less overlap?

Basic is good. Basic answer please.

Gwyn Reedy
Brandon, Florida
mailto:mgr at mgrcorp.com

 With a normally aspirated (unblown) engine, more valve
> overlap, or a larger lobe seperation angle, aids mid to upper rpm hp by
> allowing the outward flowing exhaust gasses to create a sort of vacuum in
> the combustion chamber when the piston is around tdc and both valves are
> open, where this vacuum starts to 'pull' the intake charge in before the
> downward moving piston begins to draw.  At lower rpms, it creates
> that lopey idle we all know and love, but robs low end torque.