FastKat

iTrader: (10)

How do you hookup an aftermarket regulator with stock returnless fuel rail?

Right now I have both the fuel pressure and return lines in the engine bay and the Corvette filter/regulator hooked up right behind the engine. I want to switch it out for an aftermarket regulator. The Corvette filter/regulator has a pressure, return, and engine fuel line... but it looks like the aftermarket regulators only have 2 feed lines and one return. All of the diagrams I look at show a fuel rail system with a return line, but my fuel rail is returnless.

Old Geezer

iTrader: (3)

U R short 1 line at the rail. You could add that line at 1 end of a rail, plumb it to 1 side of the regulator, and hook the line that's now on the return port of the Vette reg, to the bottom port of the reg.
Don't forget to put a filter in line B4 the rail.

FastKat

iTrader: (10)

Yea, I thought about that, but I would really like to avoid trying to tap the fuel rail for a return. It would probably be a last resort.

I did some more searching, and it looks like you can run a regular aftermarket bypass regulator with a returnless rail. I am guessing you need a regulator with at least two pressure ports. One pressure port would get the pressure from the fuel pump, and the other pressure port would go to the fuel rail. The return port on the regulator would go to the fuel return lines and back to the tank.

Does this sound right?

Here is the thread that I found (complete with diagram!):
https://ls1tech.com/forums/conversio...-plumbing.html

bayer-z28

iTrader: (14)

Install a T before the rails, plumb the T to the regulator, and run the return back to the tank.

stevieturbo

The first picture would be fine.

Although I think I'd also prefer a tee to the regulator from the main feed line as opposed to flowing through the regulator then the rails as the drawing shows. Although that would depend on the regulator itself. If it had a large body so would in no way restrict flow, I'd be happy.
Some are quite compact though

As mentioned in another post, doing it this way does have the advantage of less hot fuel getting returned to the tank as it gets heated in the rails.

In an amendment to drawing one, you could tee the supply line again so you have two parallel rails rather than them in series.

gi8e7oi825

iTrader: (32)

I'm not sure which stock returnless fuel rail you're using (early LS1? LS6? LS2? LS3?), but below is a pic of what I'm currently working on for my F-body: -6 AN bungs welded on each rear rail for rear-feed, and OEM feed becomes the return. I realize this setup, especially with a Tee in the feed, isn't going to make 9999999999 HP, but I'm okay with that lol. It sounds like you've already purchased a separate regulator... in my setup's case, I'd hook the regulator up after the return line (OEM feed) keeping the damper in place. If I end up having problems with my particular aftermarket regulator where it is, that's how I will end up changing my setup.

NemeSS

iTrader: (127)

Very crafty
It looks like it will work fine. If i woulda found out about this setup a while back. I would have def went with something similar.
When you go to set base pressure. Are you gonna use a gage on the schrader valve port?
Im using a ls3 rail with 1:1fpr to stock rail inlet and return back to tank. The stock crossover should distribute the fuel accordingly.
Ive considered using the evap line as a return. But not sure yet

FastKat

iTrader: (10)

Thanks for the info guys. I am using a stock CTS-V LSA rail. With a $400 list price, I'm not going to mess with modifying it. Here is a picture:



I was thinking about mounting the fuel pressure regulator on the back of the engine like Speartech did when they built their LS9 F-body car. That would give me a clear shot at the chassis fuel feed and return lines (located on the right and then left side of the engine bay) and also allow me a clean 90 degree shot from the regulator to the fuel rail inlet.

It looks like the MagnaFuel regulator is pretty big - I'd consider using that if it fits. FuelLab also makes a regular regulator and a mini regulator - the mini regulator would probably fit great, but it might be too small to run the fuel through the regulator. The Weldon ones look good too but they're really expensive.

Any suggestions on the "best" regulator?

JoshuaGrooms83

iTrader: (2)

anyone have any updates on their setups. id be very interesed in the pre-fuelrail install vs post.

blow thru

Ok thread dig, in the picture above with the modded stock rails will the crossover be a concern being in the middle or should it be cut off and AN fitting welded to the ends like after market rails? Is this a reliable set up?

forcd ind

iTrader: (7)

I use an Aeromotive FI reg, it has the feed and return, and I run a line over to the rails (LS3 fuel rails) I used a #8 line and a #8 fitting on the rails
seems to work fine
I also used an adapter on the end where the shrader valve is for my pressure sensor (Holley HP controller)

blow thru

Ok thanks.im planning on running a y block to split to each rail at the back, and the shrader valve to plumb in my fp gauge similar to what you have done.also with -8 feeds and return

blow thru

[QUOTE=forcd ind;17926207]I use an Aeromotive FI reg, it has the feed and return, and I run a line over to the rails (LS3 fuel rails) I used a #8 line and a #8 fitting on the rails
seems to work fine
I also used an adapter on the end where the shrader valve is for my pressure sensor (Holley HP
Sorry just re read your post. Is your reg before or after the rails?

forcd ind

iTrader: (7)

mine is before-my feed from the tank comes to the reg, and the return goes from the reg to the tank
I have a #8 from the reg to the rail (LS3 rails) they sell a #8 fitting designed to fit the rail
I use a boost/vac line to the reg, I set it to 43 lbs, then under vac it pulls it down to around 38 lbs, under boost it raises it

forcd ind

iTrader: (7)

here's a pic of mine, not sure if its clear, but I welded up a quick bracket and bolted it to the firewall and hung the reg on it-I come off the reg with a filter to the rail-in the grand scheme of things if you returned off the rails it would prob keep the fuel cooler
it wasn't a concern to me, but fuel is supposed to be 6" off the firewall for NHRA racing, the reg is but the filter isn't, but I only due track rentals anymore, lol

blow thru

Ok thanks again.i like the idea of filter in the bay for easy maintance I never thought of that.is your reg a 13101? What power you putting out?Awesome engine bay to.