Fuel Pressure Regulator

[Gruca]

I’m installing my fuel system and I’m trying to figure out the boost reference for the fuel pressure regulator. The instructions with the system says it should be boost only and on a Paxton car to use the line by the throttle body. This happens to be the same line going to my blow off valve. I also have my Boost gauge hooked up to the same line. Am I wrong or is that hose boost and vacuum? My boost gauge shows vacuum, so I would assume hooking my fuel pressure regulator to the same line would be incorrect.

 

[ViperRed91GT]

I’ve never heard of a fuel regulator that doesn’t use boost and vacuum. Base pressure is set without vacuum, pressure is lower in vacuum, rises 1:1 in boost.

 

[Gruca]

I’ve never heard of a fuel regulator that doesn’t use boost and vacuum. Base pressure is set without vacuum, pressure is lower in vacuum, rises 1:1 in boost.

That’s what I thought too. That’s why I’m confused by the instructions.

Here’s the instructions that were sent with it:

https://www.flickr.com/gp/152666373@N04/651ur3

 

[Gruca]

After reading them in the link I sent, I’m thinking I read them wrong...it looks like he meant on a positive displacement supercharged and not on the centri.

 

[ViperRed91GT]

The engine nor fuel system doesn’t know what type of supercharger is installed, nor does the operation differ, so I’m not sure why that would be a factor.


Edit: After reading, the reason he makes the difference is because of how you need to isolate the regulator from vacuum. Both types are supposed to be boost only according to the instructions

 

[Gruca]

The engine nor fuel system doesn’t know what type of supercharger is installed, nor does the operation differ, so I’m not sure why that would be a factor.


Edit: After reading, the reason he makes the difference is because of how you need to isolate the regulator from vacuum. Both types are supposed to be boost only according to the instructions

Yeah, I need to figure out how exactly to get a line from a boost pipe to the regulator. My fabbing skills don’t really exist.

 

[basspro302]

http://www.siliconeintakes.com/holset-turbocharger/-p-500.html

There are other ways also this is probably the easiest if you dont have alot of tools

 

[lshin037]

Cant you tee into the boost gauge/bov line and use a check valve like the one between the passenger side pcv to intake?

 

[Gruca]

Cant you tee into the boost gauge/bov line and use a check valve like the one between the passenger side pcv to intake?

I ended up drilling a hole in a boost pipe and tapping it to let me screw in a 1/8” NPT fitting. I connected the hose from the fuel pressure regulator there.

 

[Gruca]

Apparently my fuel pressure regulator is not increasing fuel pressure under boost. All that damn work to get the boost only line to the FPR and it doesn’t even work...FML

 

[ViperRed91GT]

Can you take a picture of where you referenced?

 

[Gruca]

Can you take a picture of where you referenced?

I was going to this morning but forgot. Will do this evening.