Tesla appears to have increased its range estimation for the Model X electric crossover.

It is now giving an estimate of 250 miles to customers invited to order the P90D Signature Series model.

The company is allowing customers who made early reservations to begin configuring cars, but this top-spec model is the only choice available, for now.

DON'T MISS: Tesla Model X Configurator Now Live; Signature Series Starts At $132,000 (UPDATED)

When the configurator first launched, it showed a range estimate of 240 miles for the P90D Signature Series.

But recently a customer posted a screenshot from the Model X configurator page showing a 250-mile range claim on the Tesla Motors Club forum.

The Signature Series model is only available with the largest, 90-kilowatt-hour battery pack. Models equipped with smaller packs will have shorter ranges.

Tesla Model X at 2013 Detroit Auto Show

Tesla Model X at 2013 Detroit Auto Show

And if Tesla offers a non-performance 90D model--as it does with the Model S--that could exceed the P90D's range.

Range may have been one of the reasons for the multiple delays to the start of Model X production.

ALSO SEE: Why Tesla Model X Electric SUV Is Late: Range, Towing, 'Falcon Doors'

The crossover is heavier than the Model S, and has a greater cross-sectional area than the sedan.

We understand that Tesla had originally counted on replacing the Model X's door mirrors with video cameras to help smooth its shape, and increase range.

But given that the National Highway Traffic Safety Administrations (NHTSA) hasn't ruled on the legality of video mirrors, that isn't really an option for the Model X at the moment.

Tesla Model X prototype [by Silicon Valley Teslas]

Tesla Model X prototype [by Silicon Valley Teslas]

This means Tesla may have had to spend more time finding other ways to boost the Model X's range to what it deemed to be suitable.

The Model X Signature Series will start at $132,000--before any Federal, state, or local incentives--but other models will be less expensive.

MORE: Tesla Delivery Goal Fell Due To Slower Model X Production Ramp: Sources

Tesla CEO Elon Musk has said that a Model X will generally cost $5,000 more than a comparably-equipped Model S.

Musk claims the first production Model X crossovers will be handed over to their owners September 29, at Tesla's factory in Fremont, California.


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