351m to 400
Postmaster
Joined: Aug 2001
Posts: 4,270
Likes: 5
From: Delaware
I simulated a 351M motor (+0.030") with 9.0:1 CR, a Comp Cams 255DEH cam, 600 CFM carb, and headers and got:
Torque = 394@2000 RPM, peak Torque = 397 @ 2500 RPM, peak HP = 308@4500 RPM.
Then I changed the stroke only and got:
Peak Torque = 456@2000 RPM, and Peak HP = 303@4500.
The reason that the 400 torque and HP drops off faster than the 351M at high RPMs is due to the lower VE as a result of the carb size and head flow limitations.
The result is 62 ft-lbs more torque at low RPMs. More HP can be obtained by improving the head flow, and increasing the carb size.
Torque = 394@2000 RPM, peak Torque = 397 @ 2500 RPM, peak HP = 308@4500 RPM.
Then I changed the stroke only and got:
Peak Torque = 456@2000 RPM, and Peak HP = 303@4500.
The reason that the 400 torque and HP drops off faster than the 351M at high RPMs is due to the lower VE as a result of the carb size and head flow limitations.
The result is 62 ft-lbs more torque at low RPMs. More HP can be obtained by improving the head flow, and increasing the carb size.
