In a couple days, Fisker will be displaying their advanced aluminum space frame used in their Karma plug-in hybrid sports car at the 2010 Geneva Motor Show. Built around their Q-Drive hybrid powertrain, the space frame focuses on strength and rigidity to house the 2.0-liter turbocharged engine, a lithium-ion battery pack, and a rear-mounted 403hp traction motor assembly.
A super-structural tunnel running down the car’s centerline acts as the Karma’s backbone. It not only houses the battery pack but acts as a torque tube connecting front and rear sections. For optimal strength the Karma’s space frame is joined with 79 meters of precision CMT MIG welds and 1,058 self-piercing rivets. Each technique is used independently only where necessary to ensure top quality and durability.
The less technical-minded of us are probably thinking “who the hell cares?” Well, torsional rigidity – the amount of twisting the thing does when put under stress – is very important for driving dynamics of a sports car. That’s why you always hear sports car enthusiasts drone on about a convertible not being a proper sports car. It doesn’t have the same rigidity of a coupe, which means it’s not quite as quick around a windy road, or more importantly, a track. Fisker wants us to know that the Karma has great strength in the frame while keeping the car as light and safe as possible.
Interesting fact – this information was released to the press over a week ago, but for some reason Fisker embargoed it until today, meaning if we want to stay buddy-buddy with Fisker, don’t release the info until now. Why they wouldn’t want the public to know about their space frame before now is a complete mystery to me.