Any idea on the cost of that kit? The one I am aware of is between $1500 and $2000.
SXViper32 - I hear where you are coming from. For a lot of manufacturing I would agree with you. Unfortunately times have changed and the idea of holding back technology in this area is no longer an option.... or a bargaining tool like it may have been in the past. It just doesn't make sense to think that a company is looking at bankruptcy, yet could have built a superior marketable poroduct... They were just holding back.
That being said, I'm sure they could improve fuel economy on any given car. They just need to be able to do that while keeping things reliable and work with the fuel available today. Sure there is the cost of Engineering, but the cost to improve fuel mileage would be small compared to the cost of a complete new model. We seem to keep getting new models, so again it wouldn't make sense that they could easily increase fuel mileage, but just choose not to. Actually if that is the case they might as well keep that "secret" with them when they go under.

FYI - The longest running GM plant just announced it will be closing it's doors by 2010. It was in business for about 90 years. The local Chrysler plant eliminated it's third shift too. Not good times for the Auto makers.