Hello.
I have a 2008 1.3 Multijet 75HP Grande Punto with a 5 speed manual gearbox which is fine but has 3000rpm on the highway. So I would like to know if a 6 speed manual gearbox from a 90HP 1.3 Multijet Grande Punto will fit in the 75HP car.
Thank you.

Don't know if it would mechanically fit, though I'd assume so as the engines are identical ...
However if you are looking for decreasing the RPMs on highway so the engine is in its max torque area (= less consumption), you need to compare both final transmission ratios and do the maths to see what improvment (in RPM) you could get with such swap.

Alternatively, you could use taller serie tyres /wheels, resulting in a longer circumferential development, with some decrease in engine RPM for an ACTUAL same speed (not the odometer one !!), but in city driving and for take off, the engine will have to push harder, whith the poor 75 that can become a pain ...

Again, one need to do maths to validate the idea, costs vs (potential) gains ...

BRs, Bernie

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