Bud,
The 14.4 is true with the original tires. Changing from the 5.50x15
Dunlop Gold Seal to a 165x15 radial drops the road speed by 3.75 mph with
the original, 5.125, gearing. The original Dunlops were even taller than
current Firestone 5.60x15.
To get back to the 50mph cruise at 3500 rpm using the Dunlops, one
would need a ratio between 4.555 and 4.875 if using radials.
Bob
On Fri, 14 Jan 2000 10:15:12 -0500 Bud Krueger <bkrueger@ici.net> writes:
> Hi Lani,
>
> The answer is 'yes'. With the standard TD tires/gearing, the
> magic number
> is 14.4 mph/1000 rpm. With the 4.55 gearing that becomes 16.2/K,
> with 4.30 it's
> 17.2/K. I seem to recall that you're up in the hilly country so the
> 4.55 is
> probably a better bet for you than the 4.3 would be.
>
> Lani Spahr wrote:
>
> > I'm going to take advantage of a Moss Motors sale and buy the kit
> to fit a
> > lower ratio rear axle into my 51 TD. My question is this: when
> cruising now
> > I run around 3500 rpm at 50 mph. What kind of decrease of rpm can
> I expect
> > with the 4.55:1 ration from Moss at 50mph? Secondly, it this a
> straight
> > ratio calculation? By this I mean:
> >
> > 4.55/5.125 = 0.8878 thus 3500 * 0.8878 = 3107 rpm
> >
> > Cheers,
> > Lani Spahr 1951 TD #5550
> >
> > Bruckner Symphony Versions Discography
> > http://people.ne.mediaone.net/lspahr
>
> --
> Bud Krueger
> http://home.ici.net/~bkrueger/
> 52TD
> 77MGB
>
>
|