Rectangular or Oval?
Racer
Joined: Jul 2005
Posts: 317
Likes: 0
From: PA
Your talking big block, oval ports are "oval" and rectangular are more square, generaly rectagular ports flow better above 5500 rpm if your talking stock iron heads, any aftermarket head tends to flow better because of better combustion chamber design. When it comes to stock heads the 781 oval castings will flow just as good as any stock rectangular head up to 5500 rpm, if you are on a budget get the "vortecs" . All depends on what your trying to do and how much money you have.
Melting Slicks
Joined: Oct 2001
Posts: 3,025
Likes: 12
From: Pleasant Grove AL
Typically, when considering stock heads, the oval ports are superior for the street, and the larger rectangular heads are superior for high RPM applications. You typically "drive torque" and "buy horsepower". You need to decide what your goal is.
Team Owner
Joined: Feb 1999
Posts: 34,454
Likes: 665
From: Republic of Texas
Racer
Joined: May 2004
Posts: 259
Likes: 0
From: Eagle WI
Here's some pictures that may be useful:
Oval port heads:
Rectangular port heads:
Here's an article about heads with flowbench data for small & big block heads, both factory & aftermarket. Scroll down to bottom of page for links to "sidebar articles" to see flow data for various heads.
Flowbench database
Hope this helps!
Rectangular port heads:
Here's an article about heads with flowbench data for small & big block heads, both factory & aftermarket. Scroll down to bottom of page for links to "sidebar articles" to see flow data for various heads.
Flowbench database
Hope this helps!
