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A Tata Nano was spotted testing on the Mumbai-Pune Expressway, and it could just be the Nano that you were waiting for. We believe Tata was doing efficiency runs on its new diesel Nano, as the two Nanos had data logging equipment onboard. It had been announced at the 2010 Auto Expo that Tata would collaborate with Bosch to make a common-rail diesel unit for the world’s cheapest car.

What it appears is that a new heavier engine has been placed at the rear which sits lower than the regular petrol Nano. Moreover, the components of the bottom half also appear different from the regular Nano.

Bosch had announced earlier in the year that it was developing a common-rail unit for the Tata Nano. Nicknamed the Bosch CRS 1.1, they mentioned that it was for a single cylinder motor. If so, then we expect the Tata Nano engine to be in the region of 600-700 cc, producing about 30 bhp of peak power but substantially more torque than the petrol unit. We expect the gearbox unit to remain the same, except with different drive ratios than the one found on the petrol engine.

Earlier, Ratan Tata had mentioned to a news outlet that the Tata Nano diesel was to be made available “sooner than expected”. Considering that production of the Nano will begin at Tata Motors new plant at Sanand in Gujarat and that production will be ramped up to meet existing demand, we expect the diesel Nano to hit showrooms before the end of 2010. Watch this space for further updates.

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