Here is the deal. If your motor makes 150hp and you boost 15psi you will make 300hp or double it. Everytime you increase or double the atmosphere pressure you double the hp on a boosted motor.
Putting in the M47 stroker crank not only increase the displacement it also gives the rods a better angle on the crank to make torque
I put a bad whooping on a lot of cars due to light weight and lots of boost on my Metric motor. I have beat the crap out of this motor and it runs perfect always. I have over 25K miles so far of brutal driving.
I always change oil timely and keep the cooling system in top shape and run a excellent tune. I'm at 2.1L and I do have the best/lightest of everything in my motor, I think mine was around $14K but I spared no expense to ensure I had the best parts and every trick that could be done on my motor.
I'm completely happy with my MM motor and still talk to the folks at Metric often and test stuff for them occasionally.
John Smith