Not sure how much could be gained there. It's a 2 into 1, it's not 3-1 or 4-1 like the yami's. Guys that did motors in the z1's were mostly drag guys and they used a new header cause the bigger turbos didnt bolt up to the stock. There's weight to be dropped for sure, but if it is at the expense of reliability or strength then I'll take the weight.