Carb question...Spread Bore? Sq Bore?
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
One has four equal-sized venturis arranged in a square pattern, one has one pair of venturis set closer together (and the primaries are usually smaller). A Q-Jet is a spread-bore carb.
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Primaries are ALWAYS smaller on a spreadbore! Spreadbores are a good option for the street. The small primaries give good fuel milage and responsiveness at lower rpms while the large secondaries give the volume you need for higher rpms.
Here is a pic of Holley's version - Model 4165 double pumper. The dual accelerator pumps do a good job of covering the "hole" when the secondaries are dumped open.
Here is a pic of Holley's version - Model 4165 double pumper. The dual accelerator pumps do a good job of covering the "hole" when the secondaries are dumped open.
