Procedure for Testing Fuel Pressure

try tee'ing the line at carb, typical mechanical pump pressure fluctuations with RPM are very... interesting



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fuel pressure regulators can help some carbs sensitive to higher pressures .

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PB is right...T it before the carb inlet. I mean, I guess it doesn't matter as you can put it on the pump discharge as well since it's a straight shot from there and only 2-3 feet of hose.

You will see some fun numbers with RPM since it is an eccentrically driven pump that is not internally regulated. Most carbs won't have issues with this as the fuel float can adequately close the flow. However, if you have a partially wet float, the pressure can flood the bowl.
 
Sorry but I don't know what you mean by Teeing it before the carb. Does anyone have a picture? I was thinking of pushing the pressure gauge directly inline with the fuel line. Is that not the way to do it?
 
I tee'd it after purchasing a Mr. Gasket 9710 and dialed it to 4.5 psi. I have a Holley 1940, I think. However, I didn't notice any difference in RPM at any pressure setting. Is that normal?
 
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