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Concept of fuel regulator?

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Concept of fuel regulator?

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Old 01-31-2005, 12:43 PM
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HungLow5.0
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Default Concept of fuel regulator?

Yesterday I was adjusting my fuel pressure. I have a BBK adjustable fuel pressure regulator. I was trying to turn the pressure down for better gasmilage so I screwed in the adjuster. Well that ended up raising the fuel pressure. I understand why is rose the pressure but what I don't get is if you tighten the adjuster wouldn't allow less fuel to run through, therefor causing better gas milage? And it's the same when you unscrew the adjuster. Shouldn't that allow more fuel to run through the regulator? Sorry if this sounds really confusing. It's kind of hard to explain it on the internet but thanks. Any input would be appreciated.
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Old 01-31-2005, 12:56 PM
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91hatchgt
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Default RE: Concept of fuel regulator?

The idea is, when you screw it in, it creates more pressure, which pushes more gas faster through the injectors, while when you loosen it up, it has less pressure, and less pressure through the injectors = better gas mileage.
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Old 01-31-2005, 01:00 PM
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mustang8719
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Default RE: Concept of fuel regulator?

Its almost like holding your finger over the end of a garden hose.When you block some of the end it creates pressure.When your finger isn't on there it is free flowing with less pressure.
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Old 01-31-2005, 02:06 PM
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roundman
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Default RE: Concept of fuel regulator?

the regulator is a type of recirculation valve which has a coil spring in it which opposes the action of a diaphragm which is moved by the engine vacuum supplied by the vacuum line attached to the regulator. the spring tries to close the valve against the pressure exerted on the diaphragm by the engine vacuum which is trying to open the valve. the more the valve is open the lower the pressure to the injectors, so at idle and part throttle the high vacuum has the valve partially open but when you go to WOT and the vacuum drops as low as it can go, the valve will be mostly closed by the spring so that the fuel pressure can go up which will allow more fuel to flow through the injectors for each milli-second they are open. so when you crank down on the spring, you are raising the fuel pressure and when you back off the spring, you are lowering the pressure. the maximum pressure reading will occur with the fuel pump on and engine off (fuel injectors closed and no vacuum on the diaphragm). when I set mine to 50 psi under these conditions, with the engine running the pressure would be about 44 psi at WOT conditions.
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Old 01-31-2005, 07:18 PM
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HungLow5.0
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Default RE: Concept of fuel regulator?

Thanks, now I understand. P.S. Your my hero! j/p
ORIGINAL: roundman

the regulator is a type of recirculation valve which has a coil spring in it which opposes the action of a diaphragm which is moved by the engine vacuum supplied by the vacuum line attached to the regulator. the spring tries to close the valve against the pressure exerted on the diaphragm by the engine vacuum which is trying to open the valve. the more the valve is open the lower the pressure to the injectors, so at idle and part throttle the high vacuum has the valve partially open but when you go to WOT and the vacuum drops as low as it can go, the valve will be mostly closed by the spring so that the fuel pressure can go up which will allow more fuel to flow through the injectors for each milli-second they are open. so when you crank down on the spring, you are raising the fuel pressure and when you back off the spring, you are lowering the pressure. the maximum pressure reading will occur with the fuel pump on and engine off (fuel injectors closed and no vacuum on the diaphragm). when I set mine to 50 psi under these conditions, with the engine running the pressure would be about 44 psi at WOT conditions.
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Old 01-31-2005, 08:07 PM
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thelast50ho
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Default RE: Concept of fuel regulator?

it raises the pressure when you tighten it cause your adjusting how much fuel it sends down the return line not the feed line
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Old 02-03-2005, 02:28 AM
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Default RE: Concept of fuel regulator?

You would think that by decreasing the pressure, that it will push less fuel through the injectors, creating a leaner condition, and therefor using less fuel. However, with a computer controled fuel injection engine, the air/fuel ratio is being sent back to the computer. In your case when you create a leaner burning mixture, your computer will see that and then correct it by widening the pulse length of your injectors. Correct me if i'm wrong, but that is how i understand it.
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Old 02-03-2005, 04:13 AM
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91LXstanger
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Default RE: Concept of fuel regulator?

hey was ur bbk fuel reg easy to install?...i have the same one in my garage, im waiting later to put it on.
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