IS THERE A FORMULA FOR CARB SIZE?
#2
Senior Member
RACING JUNKIE
Join Date: Mar 2006
Location: EUGENE,OR.
Posts: 3,391
You can run the basics on a common chart by Holley if I remember correctly. It has been awhile since iv'e done it, but I think it was like cubic inches by max RPM ... then it gives you a starting point. from there, it will help fine tune the size needed.
#3
Senior Member
RACING JUNKIE
Join Date: Nov 2008
Location: Niagara Falls, NY
Posts: 965
#5
All the racing math you'll need.
http://www.wallaceracing.com/Calculators.htm
BTW
Air Capacity & Volumetric Efficiency
Theoretical cfm = rpm x displacement / 3456
Volumetric efficiency = actual cfm / theoretical cfm x 100
Street carb cfm = rpm x displacement / 3456 x 0.85
Racing carb cfm = rpm x displacement / 3456 x 1.1
I made some of my own Excel spread sheets for carb. size and for gear ratios and tire speed with any transmission and transfer case / chain drive.
http://www.wallaceracing.com/Calculators.htm
BTW
Air Capacity & Volumetric Efficiency
Theoretical cfm = rpm x displacement / 3456
Volumetric efficiency = actual cfm / theoretical cfm x 100
Street carb cfm = rpm x displacement / 3456 x 0.85
Racing carb cfm = rpm x displacement / 3456 x 1.1
I made some of my own Excel spread sheets for carb. size and for gear ratios and tire speed with any transmission and transfer case / chain drive.
#6
Senior Member
RACING JUNKIE
Join Date: Nov 2008
Location: Niagara Falls, NY
Posts: 965
Originally Posted by DrivingMissDD
OOOoooo. nice bunch of formulas !! THANKS !!