Manthey can build a 4.4 liter with a 3.6 liter, 3.8, or even 4.0 base. It likely makes the most sense to start with a 3.6 liter motor as in the 997.1 GT3 model where the largest gains will be seen. The 3.6 starts out at 415 horsepower to gains of 115 at the crank are possible. Torque figures rise roughly 60 pound-feet. These numbers will obviously change when starting with a 3.8 or 4.0 engine base.
When racing in a naturally aspirated motor class every horse and pound-foot counts. For the serious road course junkies as well as those who just want more out of their 997 GT3 Manthey provides a tried and true tested 4.4 liter flat-6 solution. This is the best way to get significantly more power and torque out of the already high strung GT3 motor without seeking forced induction.
Press release below.