[cycleguy55]

Originally Posted by FUNFER2

Remember, a large cube small block has to work very hard, to get the same power of most big blocks. The 351/427ci sbf is real popular.

Unless I'm missing something, cubic inches are cubic inches. a large displacement small block shouldn't have to "work any harder" than a big block of the same displacement.

Some data:

• Roush's 427W crate engines ( ROUSH Performance Crate Engines ) range from 480 to 560 HP (1.12-1.31 HP/CID), and torque from 500-540 ft-lbs. (1.17 - 1.26 ft-lbs/CID)
• Brent Lykins dyno results ( Lykins Motorsports, LLC )

• FE (15 examples): 0.97 - 1.50 HP/CID, 1.08 - 1.32 ft-lbs/CID
• Windsor (425 CID+, 4 examples): 1.14 - 1.49 HP/CID, 1.18 - 1.32 ft-lbs/CID

• Ford Performance 427W & 460W crate engines ( https://performanceparts.ford.com/engines/#351 ): 1.05 - 1.25 HP/CID, 1.22 - 1.28 ft-lbs/CID

Worth noting from Brent's data is the top Windsor (445W, 1.49 HP/CID) was running less compression (10.7.1 vs 12:1) and less cam (0.700"/0.690" lift vs 0.760"/0.760") than the top FE (465 CID, 1.50 HP/CID).

There are no material differences, cubic inch for cubic inch.