How do Identify the rear end gear ratio in my 67 series V

[Blue12]

How do identify the rear end gear ratio in my 67 series V without tearing into it?

 

[Wayne67vert]

Jack the rear wheels off the ground. Spin the rear wheel one revolution and count the number of revolutions the drive shaft spins. Using a chalk mark on the driveshaft makes it easier. The number of driveshaft revolutions is your ratio.

 

[Tom H]

Follow Wayne67's suggestion BUT, note: the ratio will be either 4.21 or 3.89, both numbers are close to 4 so it's just a bit tricky. I recommend putting a chalk mark on the tire and on the drive shaft, then rotate the tire precisely 1 rotation, and watch which way the shaft turns (depends on which way you rotate the tire, of course) Look at the chalk mark on the driveshaft and you will see it will not come back to the starting point. If t it comes up almost a quarter turn past the original starting point, that's a 4.21 axle. If it comes up a little short of the starting point, it's a 3.89.

Tom

 

[ALC 68A]

How do identify the rear end gear ratio in my 67 series V without tearing into it?

As original, non overdrive Series V cars had the 3.89:1 differential and overdrive cars had the 4.22:1. It is possible that whichever is the correct one for your car, it could have been swapped for the other (or even a diff from some other car in the Rootes range), but if so the speedometer would read incorrectly. If it doesn't, then you probably have the correct one, but worth carrying out the check anyway.

 

[65beam]

As original, non overdrive Series V cars had the 3.89:1 differential and overdrive cars had the 4.22:1. It is possible that whichever is the correct one for your car, it could have been swapped for the other (or even a diff from some other car in the Rootes range), but if so the speedometer would read incorrectly. If it doesn't, then you probably have the correct one, but worth carrying out the check anyway.

The series 5 Alpines that came to the states had 4:22 gears as standard. That includes non over drive cars. This is stated on the many pieces of dealer literature that I have. The mix of the two ratios was used on series 1 thru 4. If you ordered a car you might have been able to get the 3:89.

 

[jumpinjan]

If you ordered a car you might have been able to get the 3:89.

If anyone, I think the dealer would install it. Could one actually order a car...from the UK or the US Rootes importer? I never really thought about it.
Jan

 

[65beam]

If anyone, I think the dealer would install it. Could one actually order a car...from the UK or the US Rootes importer? I never really thought about it.
Jan

Tiger Tom had a series 4 GT that was a special ordered car but that was prior to the Chrysler days. Wally Swift said that under Chrysler generic cars came into the states and the master distributor sold them to sub dealers. Options were installed by dealers. It would probably have been expensive to have a dealer install a 3:89.

 

[jumpinjan]

When my older brother purchased a used Series I in 1965, it had no heater motor (an option?). He had one installed at Lewis Auto sales here in Dayton. I actually have the original service bill that my brother received.......I also have that series I still.
Oh, the original 1500 was replaced with a dealer supplied 1600 short block (no serial numbers) when he purchased it. Just as well...
Jan

 

[Warren]

Still have a free Alpine rear end out of a automatic car in 92028

 

[ALC 68A]

The series 5 Alpines that came to the states had 4:22 gears as standard. That includes non over drive cars. This is stated on the many pieces of dealer literature that I have. The mix of the two ratios was used on series 1 thru 4. If you ordered a car you might have been able to get the 3:89.

Oh sorry - I didn't know that the US spec was different from the UK spec. Live and learn!

It seems odd to standardise on the 4.22 ratio in the US, since that gives increased engine revs at highway speeds, especially on a non O/D car. Perhaps, under US marketing conditions, Rootes considered acceleration times to be more important than maximum speeds.

In the UK, we tend to think that US driving conditions are all long distance highways at high speed. A legacy of watching films like Vanishing Point perhaps! In reality, I suspect that in period, Alpines were more likely to have been bought by town and city owners, often as second cars, to whom speed was less important than acceleration.

 

[Tom H]

ALC68A, in the 60's in the US, acceleration was the focus. 0-60 times were often the first performance spec. And as you note, most sports car buyers were not thinking about long distance trips, but cruising around town, drive-ins, etc. More like American Graffiti (great movie) than Vanishing Point.

Tom

 

[Warren]

Some places had Interstates where they stopped on the on ramp if they felt they could not merge. Some on ramps also had stop signs like leaving downtown LA going into Pasadena, hated those in a VW Bus

 

[ALC 68A]

The M25 around London is the nearest in the UK to a US style highway. There is at least one junction that has a traffic light at the end of the on slip to regulate joining traffic during rush hours.

 

[puff4]

OK, so I have an old rear that I pulled out of a non-overdrive Series V or IV back about 25 years ago, and I tried to determine the ratio using the 'turn the wheel one revolution and count the pinion revolutions' method. Linked below is my video of doing this. The pinion only turned about 2.10 or so turns with one turn of the brake drum. Hmm... any thoughts on what the ratio might be? Seems to me, given you're only turning ONE wheel that the wheel should be turned not one, but two times, since the other is not being turned, in order to get the proper ratio. Correct?

 

[Tom H]

Kevin, you have a 4.21 axle. DUH, I KNEW there was a reason I suggested 2 turns of the wheel and now I remember why. It's a differential. Ya gotta turn BOTH wheels 1 turn - or one wheel 2 turns - to get the shaft to turn 3.89 or 4.21 turns.

Tom

 

[RootesRooter]

Per the factory parts manual: SV's had 4.22's standard, but only thru VIN ...10312. The rest were 3.89's, roughly 46% of SV production.

 

[puff4]

...unless you got OD, in which case you still got the 4.22. Correct?