Thursday, May 31, 2012

More On Carburetors

Select the correct CFM Carb:
1. Engine Cubic Inches
  a. max RPM
2.Cylinder Head Used
  a. Intake valve size
  b. Exhaust valve size
  c. Intake runner volume
  a. Duration @ .050  for Intake and for exhaust
  b. lift
  c. intake manifold
      1. Exhaust
      2. single plane or dual plane
4.  stock manifold or headers
  a.  tube size
  b.  collector size

fill in as much as possible.  If your having trouble call Bobby C. Speed Connection and ask for Bobby.  We'll set you on the right path....guaranteed

Thursday, May 17, 2012

Select the Correct Carb...Bigger isn't always better

Choosing a carb that is too large will create an engine that operates too rich.

A properly sized carb will provide better drivability by creating better idle, fuel economy and throttle response.

The goal is to create an engine where all the components are matched and sized to compliment each other.  Taking the time to assure this match will result in improved driving performance and driving pleasure.

Selecting the correct carb is a function of three variables.  By correctly answering these questions, you can select a carburetor tha will meet your performance needs without creating drivability problems.

1.  Engine cubic inches

2.  Maximum RPM.  You must be very realistic here.  Most stock and mild aftermarket cams are          designed to max out at 5000 RPM.

3.  Engine efficiency.  In general terms this measures how well your engine moves the air/fuel mixture throughthe engine.  This number is affected by many engine components including the carb,  manifold, cylinder head, camshaft and valvetrain components, piston and combustion chamber design, and exhaust system.

Next week I'll post the entire checklist that you'll need to fill out in order to purchase the proper size carburetor.  Or you can call me and I'll  fill it out and order it for you.

Bobby C.

Do it Right, Do It Fast at Bobby C. Speed Connection