what gives you torque? (advice for a dummie)

[firefighter3931]

Nice explanation Duey !   While the stroke and rod ratio have an impact on torque production....the heads and cam also have a large role as well. The factory heads can become a limiting factor due to the (small) cross sectional area within the port and it's subsequent volume. A stock iron head is actually quite small, comparatively speaking, for a 440ci engine. That is why the oem cam profiles are all specced out on wide LSA's...to flatten out and widen the powerband. Throw a bigger head on the same motor and you can extend the powerband and increase the horsepower.

Stock 440's made peak hp at 4700 rpm. Designing an engine package to pull hard to 6k will make more power (hp) and keep the tq #'s intact. It's all in the combination.  

Ron