drill the side of the tank, use a bulkhead fitting. use POR 15 tank sealant between the nuts securing the bulkhead to the tank.

dunno, just a random idea

 

Return line option

Here's the return line insert I was talking about earlier. I haven't looked at (for proper amount of straight tube on our tanks), or measured the size, but it might work. I actually have one of these sitting in my closet

 

Sounds like a complicated mess for no gain at all. JB Weld will out last your car.

 

Could of sworn the ECU messed with fuel pressure in our cars.

Has anyone actualy converted over to a return style?

 

I think I've read somewhere on here that someone tested the fuel pressure through a run and it really didn't change at all. Actually I'm pretty sure I did (but I won't say 100% till I duct tape my gauge to the window and do it myself or someone confirms)

 

You don't have to install a return line, there is already one there, it comes from the fuel filter. Replace the filter with a 1 in/1 out style (factory is 1in/2out) and the return line that is left over can come from the rail and just needs a quick release fitting installed to mate to the factory return line.

 

I never even thought about that! Great way to do it.

 

The only portion of return line you would have to install would be from the rail to the factory fuel filter, no tank or fuel filler cutting is necessary.

 

Awesome! I didn't even know that was there!

 

You can look at the fuel filter and see the two outlets, its right behind the rear suspension in the middle of the car iirc.

The tank will still have to be dropped and the in tank regulator needs to be removed from the pump assembly. Its a small stainless piece that has a ball type valve held down by a stainless sprung lever. This is what the return line from the filter runs to....the pump continously runs fuel through the filter and back to the tank, greater amounts during idle/cruise and less during WOT as rail demand increases.

 

What a weird setup, I've never noticed it. I'm glad it's like that though. Really simple to setup. What regulator are you running?

 

AEM, but any will work, boost compensating is best for our setups.

I'm using a rail from a 2002 Cavalier LS Sport. Its identical to ours except it has a return fitting tapped over number 2 injector (ours is cast there but not tapped). I have a spare fuel pump assembly I butchered to see if I could remove the regulator without issue and also to shop around for pump options. I'm still up in the air on whether I want to replace the in tank pump or install an inline one. I think the Walbro GSS341 will fit in tank but I'm not certain.

The project got put on hold for a while when we were building PpAzZ's turbo 2.4 but I'm working on it again since a certain turbo redline owner is running 650cc injectors at 110% duty cycle. This should help alleviate the problem and allow us to run 750cc injectors.

 

What boost compensation ratio are you running? Also was the regulator (the one in the tank) able to be removed without issue?

 

I don't have the system installed yet. Its a 1:1 regulator. Yes, the in tank regulator can come out and nothing needs to be put back in its place as far as I can tell.

 

****, one more thing. Is it an adjustable regulator? I know that on other pcms (older ones so I'm sure this one is the same) an adjustable regulator works but only for a very short time. The pressure stays the same but pulse width changes to get the afr back to where it's supposed to be. I'm assuming it's an adjustable and you will be using HPT to adjust for this correct?

 

The end of the rail has a pulse dampener for the pump and the injectors. The regulator simply allows high pressure to match manifold pressure and lower pressure during vacuum conditions.

The stock PCM has an "Injector Flow Rate" table to account for changes in manifold pressure by compensating with additional pulse width. This table can be flatlined with a return style system.

 

I know what the regulator does, I guess I can't word things right I was wondering if the one you are using was adjustable, and what could be done to keep the pulse width the way you wanted it (as without tuning the pcm would shorten pusle width if the pressure was higher than what's normal). But looks like you answered me anyway (injector flow rate table). Interesting about the end of the rail. I've often wondered what that was! Makes sense to help neutralize the pulses of the pump and keep pressure steady without a return line.

 

The fuel pump also has a flex pipe to absorb some of the vibrations as well.