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Differential Ratio

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  • 2 weeks later...
Abo Bob Grand Master

Abo Bob

Posted
Posted

Not necessarily doubting you Mark but auto diffs are usually longer. In the R34 the auto is 4.089 and the manual is 4.111. I know that's close enough to be almost the same but you see whatI mean?

I thought the R33 auto diffs were 3.9xx but I've got nothing to back myself up there. :cheers:

Cubes Grand Master

Cubes

Posted
Posted

From what I understand the auto R33 diff is a 4.3 and the r33 manual diff a 4.1.

The R32 Turbo's run the same diff ratio for both the auto and manual being a 4.3.

Abobob, The reason for the r34 ratio being different may be due to the gearbox ratio's. The R32/R33 auto's run quite a long first gear. If they were to run a 4.11 ratio behind the auto they would be looking at almost 70km/h out of first.

wrxhoon Grand Master

wrxhoon

Posted
Posted (edited)
Not necessarily doubting you Mark but auto diffs are usually longer. In the R34 the auto is 4.089 and the manual is 4.111. I know that's close enough to be almost the same but you see whatI mean?

I thought the R33 auto diffs were 3.9xx but I've got nothing to back myself up there. :happy:

In older cars when you had top gears with 1 to 1 in both manual and autos, autos always had lower ratio diffs ( lower number but actualy higher diff, longer legs). The reason for that, the torque converter in the auto slips so it makes easier to take off and because it slips lower high speed .

Most late model cars don't use a straight gear anymore and most autos have a very high top gear ( around .7-.8 to one, even lower) . Thats the reason you don't need a higher diff in autos now so it wouldn't surprise me if the auto was the same as a manual. These days most cars have a lock up converter in top gear ( even top 2 some of them with 5 or more ratios) .I have no idea what the skyline ratios are though.

Edited by wrxhoon
Cubes Grand Master

Cubes

Posted
Posted

On that note I have a rear diff ratio of 4.375 thats in good nick if any one wants it? >_<

I bought a GTR diff that already had the swap done to it. Its in excellent condition but I'm keeping the centre and half shafts. I'm selling just the diff gears (pinion and crown) or the pumpkin if the individual wishes not to stuff around refitting the pinion to their pumpkin.

I was hoping for a set of 4.11's to go behind the rb30. Bugger. :)

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