Yes, it makes a difference even for the street.
I have tried this in an L28. Not a big deal but
less wear on the piston skirt too. U & R engines
already have very long rods compared to what
later engines have.
Thomas
Vicki Burrows wrote:
> And there is lots of theory, but what actual real-world, documented HP
>difference
> on a street car is there? Outside of extreme differences in rod length,
>probably
> not much...
> Greg Burrows
>
> Thomas - Sweden wrote:
>
> > If the piston stays at TDC and BDC for too long the
> > engine will loose some power. Specially in engines with
> > less than 8 cylinders. This can be reduced by using shorter
> > rods but if the rods are too short the friction will increase
> > due to the side loads on the piston caused by the rod being
> > in a greater angle to the cylinder, halfway up or down in the
> > cylinder. Somewhere there is an optimal rod vs stroke length
> > and by looking around a little it seems like many of the high
> > performance engines are close to the 1.70:1 ratio.
> >
> > Thomas
> >
> > datsunmike wrote:
> >
> > > I think it has to do with how much time the piston stays at TDC and the
> > > speed of the piston during the stroke a/k/a piston speed.
> > >
> > > I've read many articles and everyone has their own opinion with what's
>best.
> > > Since I don't own a car that you can get different rod lengths for, it
>went
> > > in one ear and out the other, but then again I don't remember too much
> > > anyway - if I did I never would have bought another old car :)
> > >
> > > Mike
> > >
> > > ----- Original Message -----
> > > From: "Gordon Glasgow" <gsglasgow@attbi.com>
> > > To: <datsun-roadsters@autox.team.net>
> > > Sent: Thursday, January 23, 2003 9:04 PM
> > > Subject: RE: Connecting rod length (somewhat OT)
> > >
> > > > Smokey Yunick thinks you should run the longest rod you can fit in the
> > > > engine (and he has some fairly compelling evidence to support that
>claim).
> > > >
> > > > The NASCAR guys have experimented with it and come to the same general
> > > > conclusion. I can't point to the exact issues, but I remember seeing
>some
> > > > articles in Circle Track about it a while back.
> > > >
> > > > Dave Coleman made the "1.70:1 is optimal" claim in Sport Compact Car a
> > > while
> > > > back, but their online archives don't go back far enough.
> > > >
> > > > I searched Google on "automotive engines connecting rod length" and got
> > > back
> > > > over 2000 hits.
> > > >
> > > > Gordon Glasgow
> > > > Renton, WA
> > > > www.gordon-glasgow.org
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