Ford Mustang Forums banner

1 - 2 of 2 Posts

·
Registered
Joined
·
749 Posts
Discussion Starter #1
I recently installed a BBK fuel pressure regulator and liquid filled fuel pressure gauge on my notch. I installed the gauge in the rail where the fuel pressure check valve was.

I tweaked the car, so that when it is hot, and has been running for 30+ minutes it reads 38 PSI on the gauge with the vacuum line disconnected. However, when the car is cold, the gauge will read upwards of 44 PSI with the vacuum line off.

Is this normal behavior? It kinda sucks that my fuel pressure depends on how hot the car is. Makes it impossible to tune.
 

·
Registered
Joined
·
980 Posts
Your problem may be associated with the sealed gauge. As the gauge heats up, the pressure in the gauge rises. Remember you are measuring FP against atmospheric pressure. If the atmosphere in the gauge is under more pressure (from the heat) it will read lower than it really is. Get a non liquid filled (vented) gauge.
 
1 - 2 of 2 Posts
Top