WebMar 25, 2010 · I have 11 vacum at best at idle. i run a 4.5 power valve. ( thats the way i have been tought to select the powervalve size ..vacum at idle divide 2. if it lands on a number thats not a powervalve size then go the next size down) i … WebFeb 27, 2007 · Dropping the jetting to 80 would be good. If you are flooding the motor the PV might be open. It is definitely a good idea to go with the 4.5. If you still can't get your idle circuit right you can install .015 wires in the idle circuit. The mixture screws on the sides of the carb should be out 1 1/2 turns from closed.
How do Holley Power Valves affect idle AFR? - Speed-Talk.com
Webpower valve. If your reading divided by 2 lands on an even number you should select the next lowest power valve. EXAM-PLE: 8” Hg vacuum reading divided by 2 = 4 power valve. Since … WebThe power valve is important because of its effect on everyday, around-town drivability. Show More. The rule of thumb for power valve size selection is to divide your highest part throttle manifold vacuum reading by two and select the closest size smaller. Example: 8" Hg of manifold vacuum would use a 3.5" Hg power valve. Holley power valves ... the daily news headlines
Holley Power Valves - JEGS
WebMar 4, 2002 · One book I have says to take a vacuum reading and divide by two and add .5. Lets say the engine is idling at 20 inches of vacuum.20 divided by 2 plus .5 = a power valve size of 10.5.The other book I have says to go 2 numbers down from vacuum reading.An engine idling at 12.5 inches would get a powervalve of 10.5.What is the deal? B BB_Mike WebTo properly size a power valve, take a vacuum reading at idle and if it is above 12" for a standard transmission a 6.5" will be safe to use. For automatic transmissions take a vacuum reading in gear at idle and if the vacuum is below 12" divide that in half for proper size. Example 9" of vacuum in gear at idle will require a 4.5" power valve. WebApr 25, 2005 · Holley power valve is stamped with a number to indicate the vacuum opening point. For example, the number "65" indicates that the power valve will open when the … the daily news iron mountain mi obituary