[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: 2.5/2.6l (was k24/26 hybrid aka RS2) - Crank, Rods &clearances??
> What are the negatives to using shorter rods?
The rod length itself isn't really the issue but the *ratio* of the stroke to
rod length ... this determines the acceleration rate of the piston assembly,
the length of time it dwells at the top and bottom of the stroke, the degree
of angularity it has during the power stroke, etc. All of these factors will
also influence cam design, valve sizing, etc.
Deciding which ratio is best for a given application means deciding which
compromises are most and least important ... I'm not trying to evade
answering your question but books could be written on this subject and I'm by
no means an expert. This is why I'm still holding onto the Eurovan blocks
until I determine whether I've built the best 2.5L motor for my needs ... if
not, I can have new rods or pistons (or both!) made and see how well a motor
built around a longer rod ratio works.
In theory, anyway ... I'm not sure I want to make a career of R&R'ing turbo
motors from Audis!