S54 5th Gear Overdrive

[webb2800]

I've got a fairly straightforward question regarding the S54 transmission. On a UK model 3S-GE, is 5th gear considered an overdrive gear? (as in a gear with a ratio less than 1:1, or meaning 4th gear would achieve a higher top speed)

Thanks

[BYRNEY1984]

I've got a fairly straightforward question regarding the S54 transmission. On a UK model 3S-GE, is 5th gear considered an overdrive gear? (as in a gear with a ratio less than 1:1, or meaning 4th gear would achieve a higher top speed)

Thanks

I believe these are the gear ratios for the S54 box
3.285 1.960 1.322 1.028 0.820 Diff: 3.944
Hope this helps

[nick]

As the car will not pull anything near peak revs in 5th, I would call it an overdrive, like most moderns. The gearing is arguably odd, as it is slightly faster in 5th than 4th.

[webb2800]

yeah, looking at those ratios Byrney gave is interesting. Plugging them into a calculator gives ~127mph top speed in 4th and ~159mph in 5th (Standard wheel/tyre height, 7250 rpm). I'd be suprised at a standard n/a hitting 140. In real terms 5th is only getting you that final 10-15mph when talking purely top speeds.

So, not technically an overdrive but certainly fuctions as one in any practical capacity.

[Tallboy]

As the car will not pull anything near peak revs in 5th

i beg to differ it will it just takes time to get there, im talking rev 3 na