Technical Gearbox - road speed per 1000 rpm

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Technical Gearbox - road speed per 1000 rpm

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Hi

Long time since I was last on here, hoping for some info!

Car is 1.2 lounge 2012 with 5 speed manual gearbox.

Long story short - at 48K miles 7 years old I had to have a replacement gearbox fitted (bearing failure), so have bought a refurbed one one from an online seller, who has been helpful.

The new gearbox has been fitted and drives well, but the shift light on the dashboard comes on in 5th gear. The mechanic and gearbox supplier are baffled, could the replacement be a wrong 'box? The RPM at 60 is 3250 which maybe seems high (I found some old figures in a Review which quoted 22.5mph per 1000 rpm in 5th gear which would be around 2700 rpm at 60mph.

Does anyone have the correct figures or a reason as to why the shift light comes on in 5th?

Thanks!
 
The RPM at 60 is 3250 which maybe seems high (I found some old figures in a Review which quoted 22.5mph per 1000 rpm in 5th gear which would be around 2700 rpm at 60mph.


Hi.

It certainly looks like the wrong 'box has been fitted; on a 1.2 500, you should be looking at around 2200rpm at 50mph, which is about 2650rpm at 60.

I'll see if I can find some actual data - it's not as easy to come by as you might think.*

There are certainly differences in the ratios between different engine types in the 500.

*Edit: I've attached the ratio tables for the 500 if you want to do some basic math.
 

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Thanks - I found this useful site

https://www.automobile-catalog.com/auta_details1.php

1000rpm speed:

(km/h/mph)

I: = 8.2 / 5.1

II: = 14.8 / 9.2

III: = 21.6 / 13.4

IV: = 28.6 / 17.8

V: = 35.7 / 22.2


Final drive ratio std:

3.44

Shows 22.2 Mph / 1000 rpm in 5th gear so 2700 RPM @ 60mph.

Just wondering which gearbox this could be with lower gearing?
 
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Could it be the 6 speed box?

I just checked the data for the 6 speed box from the 1.4 and this looks right for 5th gear in the 6 speed box (18.3 mph / 1000 rpm).

Would this box fit the 1.2?

If it did would the simple option be to fit the gear selector from the 6 speed box instead of changing the gearbox again?
 
I just checked the data for the 6 speed box from the 1.4 and this looks right for 5th gear in the 6 speed box (18.3 mph / 1000 rpm).

Would this box fit the 1.2?

If it did would the simple option be to fit the gear selector from the 6 speed box instead of changing the gearbox again?

My advise would be "just get the correct box for the car" or you may end up spending more and having more issues, add to which the engine speed is likely similar so why add an extra cog once in top?
 
There are no slots, I know its a mini Ferrari, but no slots. Its all set up at the gearbox end.

D

There must be some sort of "locating mechanism" at the base of the gear stick, otherwise it would move around when in gear, as if in neutral? Yes its not like the gated "H" of a Ferrari I agree.
 
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