I planned to use this Holley 12-848 regulator fro my TT build. Im running a -10 feed line split to the back of both rails, then two separate lines off the front of the rails into the regulator. Just noticed that the Holley piece labeled one side as the inlet, and one side as the outlet, so can I not run two lines into this thing?

I called them but the tech rep sounded like a crayon eater when I asked him. I don't think he had any business being a tech rep lol. Anyways, so can an outlet on a FPR be used as an inlet?

 

No, it can't. Split it after the regulator and pre fuel rail. How big are the inlet and outlet ports on that regulator?

 

They are -10.

 

Just tee or Y the rail exits together into a single line for the regulator.

Edit.

Can you blow through that "inlet" and "return" as marked in that photo ?

If so, then yes you can run a return from each rail to each side port.

Bloody weird anyone would ever label a regulator that way. That's like an old carburettor setup type of labelling.

 

By blow through you mean they both enter to the same passage? I believe so, but was a bit hesitant to open the package and check seeing how I may need to return it for something else.

 

Yes. If there is free passage between both sides then you can use it as normal.

As I say, it looks like they've just used very old labelling fr some weird reason, as they would label a carb style return regulator, with the actual feed to the engine being a dead end.

You could use that regulator either way really.

 

There are only 3 ports right? You can't use 2 of those 3 as rail supply lines. There would be no inlet from the pump then. "Y" or "T" it after the regulator...

 

Awesome thanks, gonna open it up and take a look at the passages. Is there anything wrong with mounting the regulator directly off the rail like this picture? I'll have two feed lines to the back of the rails off a Y.

 

The in and out as labeled there are a common passage.
I'm using one.

I plumbed mine like the diagram shows. After the rails. So I have one port capped.
Ret to the tank. Return is -8 BTW.

Ron

 

It is a totally normal FPR, with 2 inlet ports and 1 return.

It's just labelled incredibly stupid for a modern EFI application.

Connect as you would any typical FPR.

ie one rail exit to each side port if you wish to configure it as such.

 

Thanks Stevie, I'm looking for a specific answer to the question in post #8, I would really like to mount the regulator just like the picture of my buddies car, with it basically on a front crossover. This seems like it would make the most sense, and get rid of having a line off each rail to the FPR if it were mounted on the firewall or a wheel well etc.

I'm a bit hesitant though, because I don't know if it would be better to have those lengths of hose? Is there any reason why mounting it up like the picture is a bad idea?

 

Hose lengths are not an issue ( within reason of course ).

Personally I would not solid mount the regulator to the engine ( or the rails ). It most likely is fine, but vibration, risk of fatigue on the fittings with the weight hanging on them etc.
I would always remote mount the FPR.

And you dont have to have a line from each rail to both side ports. You can simply tee them and run a single line into one side of the reg ( blanking off the other side of course )...as Ive had mine for nearly 10 years.
It's simple and less hoses.

But as said earlier there are almost dozens of ways you could do it.

 

man you really like orange huh?

 

Not my car, but yes he does haha.

 

well thats good