[Stan Weiss]

Someone please help me out with this slow velocity thing.

I keep hearing about slow velocity and numbers around 250 fps.

280 cc intake port with a 5.3" port length has an average CSA of 3.2239 sq. in.

an average CSA of 3.2239 sq. in. that flows 380 cfm has an average velocity of 282.89 fps

Taken from a simulation done using Larry Meaux PipeMax Program
--- 7500 RPM Intake Cross-sectional areas in Square Inches ---
350 FPS CSA= 2.554 Port has Sonic-Choke with HP Loss ( too fast FPS )
330 FPS CSA= 2.711 Port may have Sonic-Choke with HP Loss ( too fast FPS )
311 FPS CSA= 2.877 Highest useable Port velocity ( possible HP loss )
300 FPS CSA= 2.982 Smallest Port CSA ( Hi Velocity FPS • good TQ and HP )
285 FPS CSA= 3.139 Smallest Port CSA ( very good TQ and HP combination )
260 FPS CSA= 3.441 Recommended average Intake Port CSA (very good TQ and HP)
250 FPS CSA= 3.579 Largest recommended average Intake Port CSA ( good HP )
240 FPS CSA= 3.728 Largest recommended average Intake Port CSA (less Peak TQ)
235 FPS CSA= 3.807 Largest recommended Intake Port Gasket Entry area CSA
225 FPS CSA= 3.976 Largest Intake Port Gasket Entry CSA ( Slow FPS )
215 FPS CSA= 4.161 Possible Torque Loss with Reversion ( Slow FPS )
210 FPS CSA= 4.260 Torque Loss + Reversion possibility ( too slow FPS )
200 FPS CSA= 4.473 Torque Loss + Reversion possibility ( too slow FPS )
Note : these are calculated average Port cross-sectional areas and FPS

Stan