There would be major clearance problems with turning turbo turbo's on these cars.  Also, more turbo's more things to go wrong no matter how you look at it.  If you look at most of the twin turbo factory cars, people are going back over to a single turbo to make more power.

Another problem with these cars is even 1 turbo has clearance problems.  There isn't a lot of room for 1 set of pipes, let alone 2 sets of pipes.

You even said yourself price and weight play a problem with those turbo chargers.  I never did look into pricing on one of those.  But we are already having people complain about the pricing of this turbo kit.  So we are trying to keep the price of this system as low as we can and still keep quality parts.

We also trying to use this same kit for the 2.5 and the 3.0.

340 hp turbo is kind of on the small side.