How about "There's no replacement for displacement!"
One thing that OHC brings to the table is improved ease of cylinder head
design. One big drawback to the old hemi was the complexity of the
pushrod path to get the rods spayed to get to the splayed valves. With
an OHC design, pushrods are eliminated, obviously. OHC designs are also
easier to equip with multivalve combustion chambers. Harry Westlake, an
English engineer, designed a four valve pushrod head for the small block
Chevy back in the '70s, but the complexity was impossible to overcome.
Skip
SoCal DOC
Patrick Delgado wrote:
>
> Given the same size and flowrates, The method(ohc v.ohv) of operating
> the valves has NO EFFECT on hp/tq. That is controlled by cam profile.
> OHV's are cheaper to make, OHC's are better from any mechanical point
> of view. Ignition, fuel control, cam profile and the mass and balance
> of the rotating assembly(not valve train) dictate how an engine will
> "lug".
> You're right about displacement. BRING ON THE 6.1's.
> Dr. Pat
> ----------
> >From: Shaun.Hendricks@bergenbrunswig.com
> >
> the very thing that limits the pushrod engines in RPM's is
> > the same thing that gives them good torque. The additional mass in the
> valve
>
> The problem is, we lost engine size as
> > well, and in the end, that's what really hurts... as the saying goes:
> there's
> > no substitute for cubic inches! (or even: SIZE DOES MATTER!)
> >
> > Shaun H.
> >
-- Shadowcatcher Imagery http://members.tripod.com/~shadowcatcherimagery/index.htm
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:19:03 EDT