Originally feted for its added lightness, the Lotus Seven has always been a heavyweight of the homage car business. Today's Birkin is just one of a bunch, but will its price make this Seven the one?

What's in a number? Well, if that number happens to be 7, then a lot. There's seven days of the week, seven deadly sins, and Seven & Seven, a tasty beverage old people drink. In mathematics, seven is not only a (one of only 47 so far discovered) but also a double Mersenne prime, itself being an exponent of another Mersenne prime. And in the world of venerated automotive appellations, seven is the name given to the most lardasstical of BMW sedans one of the most basic and elemental of sports cars ever created.

How elemental? Well, if the Lotus 7 were to appear in the periodic table, say as Sevenium, its lack of mechanical or structural ostentation would have it fall within the family of noble gasses. And, like so many members of that class, the original Lotus car came and went with the etherial economy of one of Casper the friendly ghost's otherworldly farts.

These days, the world is heavy with cars that pay obeisance to that original lightweight Seven, from England's Caterham, to the Dutch Donkervoort, and the Birkin of Durban, South Africa. Today's contender is one of the latter.

John Watson, the founder of Birkin Cars, is a descendant of race driver and jaunty scarf aficionado, , for whom he named his kit-manufacturing business. More rare in the U.S. Than Caterhams and Westfields, the Birkins are also more true to the original S3 Seven in its design than either of those Brits. This (masquerading as a '69 Lotus) is appropriately Ford powered, however lifting off its featherweight polished aluminum hood reveals not a kent cross-flow, but a modern 2-litre ZTEC ZX-1. Behind that is an SPC close-ratio 5-speed that's also from the house of Henry, and power gets doled out to the rear wheels through a Quaife LSD diff, which centers a 5-link axle.

A Birkin, or hell, any Seven, is not necessarily the best choice as an all-weather ride, but this one still comes with a top and doors, although if you haven't ever tried assuming the lotus position, folding yourself up to get into one requires Cirque du Soleil level flexibility and shouldn't even be a consideration for those also thinking about getting the Lap Band.

Once inside you'll find the accommodations spare, uncompromisingly tight, and in the case of this car, covered in leather. That cabin is so small that everything you need can be found within an eyelash's reach, and everything you don't wouldn't fit if you tried.

That's a big part of what goes toward this car's approximately 1,400-lb weight, dripping wet. That, coupled with the engine's claimed 160-bhp makes for 8.75-lbs per pony, and more fun than the proverbial barrel of monkeys- which also, by the way, would weigh more. This Birkin is being offered in California, home to the nation's most onerous auto registration requirements, but it still carries the Indiana plates and title it had when it was in that midwestern state.

Today, the car has an asking price of $22,500, and a claim that it can be registered in Cali, or anywhere else for that matter, as it has the VIN of a '69 car. The question however, is whether this Birkin is worth lightening your wallet to the tune of $22,500? What do you think, does that number make this number look like the right number for you? Or, Does that just not add up?

You decide!

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