I think what Fred is saying (I haven't done the calculations to know
for sure) is that 2.957 in 1st with 3.70 rearend rotates the tire at
the same rate as 3.117 in 1st with 3.90 rearend. In reality 2.957 is
2.957 - that defines the ratio of driveshaft rotation to engine
rotation; the driveshaft turns once every 2.957 turns of the engine,
right? But then it goes through the rearend and turns the wheels, and
the wheels cover so much distance depending on their cicumference, so
speed of the car at a given RPM, gear ratio, and rearend ratio changes
once again.
Ugh! I think I'll leave my transmission and rearend alone and get some
15x6 Panasports and 195/50/15 tires because they "look cool". By the
way, anyone have the exact offset (if any) needed for 15x6 Panasports
on a 1970 Roadster with stock rear springs and comp front springs?
Thanks,
Adam
1970 SPL311-28181
1967 SPL311-08240
--- "Patrick P. Castronovo" <slick1@mohaveaz.com> wrote:
> You have the gearing wrong. 5 speed:
>
> Fred
> Chilton
> book
>
> 1st 3.117 2.957
>
> 2nd 1.958 1.858
>
> 3rd 1.382 1.311
>
> 4th 1.054
> 1.000
>
> 5th .898
> .852
> Pat
>
> -----Original Message-----
> From: Fred_Katz@ci.sf.ca.us <Fred_Katz@ci.sf.ca.us>
> To: datsun-roadsters@autox.team.net
> <datsun-roadsters@autox.team.net>;
> Michael Poorboy <bitterrootprop@nidlink.com>
> Date: Thursday, February 08, 2001 2:18 PM
> Subject: Re: Roadster gear ratio's
>
>
> >Mike,
> >
> >So if you have a 1600 rear end 3.9, with a 5-speed trans then you
> get the
> >following?
> >
> >5-spd with
> >1600 Rear end standard : 3.9
> >
> >1st Gear : 3.117
> >2nd Gear : 1.958
> >3rd Gear: 1.382
> >4th Gear: 1.054
> >5th Gear: .898
> >
> >And with smaller than stock wheels, that moves the 5-spd values for
> 1st,
> >2nd, 5th even closer to the stock 4-spd values for 1st, 2nd, and
> 4th. Very
> >interesting!
> >
> >Fred - So.SF
> >BADROC
> >'66 with 2000/5spd.
> >
> >___________________ Reply Separator _________________________
> >>Subject: Roadster gear ratio's
> >>Author: Michael Poorboy <bitterrootprop@nidlink.com>
> >>Date: 2/8/2001 12:43 PM
> >>
> >>List,
> >>I found my manual so here are the numbers for the Roadster:
> >>
> >>1600:
> >>
> >>Rear end standard : 3.9
> >>
> >>1st Gear : 3.382
> >>2nd Gear: 2.013
> >>3rd Gear : 1.312
> >>4th Gear : 1.00
> >>
> >>
> >>2000
> > >Rear end gear standard : 3.70
> >>
> >>1st Gear : 2.957
> >>2nd Gear : 1.858
> >>3rd Gear: 1.311
> >>4th Gear: 1.00
> >>5th Gear: .852
> >>
> >>And the calculator link again is :
> >>
> >>http://www.geocities.com/z_design_studio/
> >>
> >>Thanks,
> >>Mike
> >>Nowroc
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