View Single Post
  #15 (permalink)  
Old 07-04-2008, 09:55 PM
RICK LAKE RICK LAKE is offline
CC Member
Visit my Photo Gallery

 
Join Date: Mar 2001
Location: E BRUNSWICK N.J. USA,
Posts: 3,841
Not Ranked     
Default There are some good articles about heads and flow numbers

Hound Dog there are some good articles about basic heads, flow numbers, camshafts, weather swirl is better than straight shot into the cylinder. The importants of velocity of the A/F mixture. It comes back to the biggest head is not always the best head. It just means that with the right carb, camshaft, piston design, exhaust system, you can get the most power at a certain RPM range. Big head suffer in the 100-300" lift range and make it up in the 300-700+" lift range on the cam. I am not a pro, but have seen enough motor put togeather with the best parts and the motor runs like a pig. Again you can't compare a Ford head to a SBC head. I good motor to pick on is the Boss 302 from 1970. A pig from idle to 3,000 rpms, after that to 7,200 rpms hauling a$$. Why, Big ports. We are talking about stock motors from the factories. 302 Chevy was about the same. The rough ideal proportions are about 50-54% on the intake side and 38-42% on the exhaust for almost any motor. This is the valve size in respect to the cylinder bore size. You are hoping for an 84-94% VE ratio of the motor running. In the 90's is a solid strong motor maken great power and use of the A/F mixture. There is alot more than just this but I think you get the idea. I am not a pro builder. I do know that parts are made for certain applications. Matching the motor rpm range for power is the most important thing. I like torque motors over HP motors. Torque is what moves the car, HP is a by product in the upper rpms. It's a balancing act. Rick L.
Reply With Quote