Fuel line ideas?

[marine02ss]

I have a 68 camaro Im working on.I have dual intank walbros with a -8 fitting out of tank.Where should I mount the regulator near the tank or close to the engine.Ive heard pros and conns either way.Its a Fuel Lab regulator should I run the return all the way from the engine?Its a 408ci with Kenne Belle blower,AFR225s,etc....Here are some pics of my project:

Couple more pics on the ground,mounted the Fiske wheels and the steering column.

http://i120.photobucket.com/albums/o189/marine02ss/100_2080.jpg
http://i120.photobucket.com/albums/o189/marine02ss/100_2087.jpg
http://i120.photobucket.com/albums/o189/marine02ss/100_2082.jpg
http://i120.photobucket.com/albums/o189/marine02ss/100_2098.jpg
http://i120.photobucket.com/albums/o189/marine02ss/100_2085.jpg

[marine02ss]

Little Update:304 SS mandrel tubing
http://i120.photobucket.com/albums/o189/marine02ss/DSC00378.jpg
Exhaust work
http://i120.photobucket.com/albums/o189/marine02ss/DSC00380.jpg
Tack welded
http://i120.photobucket.com/albums/o189/marine02ss/DSC00384.jpg
Trial fitting
http://i120.photobucket.com/albums/o189/marine02ss/DSC00381.jpg
http://i120.photobucket.com/albums/o189/marine02ss/DSC00371.jpg
Made power steering hose

[marine02ss]

Couple engine pics:
http://i120.photobucket.com/albums/o189/marine02ss/DSC00369.jpg

http://i120.photobucket.com/albums/o189/marine02ss/DSC00368.jpg
http://i120.photobucket.com/albums/o189/marine02ss/DSC00370.jpg

[XcYZ]

I have a 68 camaro Im working on.I have dual intank walbros with a -8 fitting out of tank.Where should I mount the regulator near the tank or close to the engine.Ive heard pros and conns either way.Its a Fuel Lab regulator should I run the return all the way from the engine?Its a 408ci with Kenne Belle blower,AFR225s,etc....

Awesome pics! That's going to be a great car. :cheers:

I'm running my regulator right outside the tank and dead heading the system.

[Payton King]

reg at tank.

[Speedster]

Blowers like more fuel. Is yours EFI or Carb? The whole concept of deadhead vs. return is fuel inertia. It takes a good pump to get the volume of fuel in the line moving against both high acceleration g-forces and high blower boost. Like anything else, depends on how you intend to drive your car. Dead head is fine for 95% of the cars.

[Pantera EFI]

When you "fill" your "dead head" with fuel vapor (bubbles), your engine will "hurt". There is no float in an EFI system.
Please allow the VAPOR to return to the fuel tank.

Lance

[XcYZ]

Sure, there are pros and cons to both ways, but the dead head system works great.

[camcojb]

When you "fill" your "dead head" with fuel vapor (bubbles), your engine will "hurt". There is no float in an EFI system.
Please allow the VAPOR to return to the fuel tank.

Lance

I know you're an EFI guy and I'm just a hobbiest, so please explain how this is any different than running the regulator off the back side of the rails. Any bubbles still go through the rails first, right past (and into) the injectors. Even if regulated on the inlet side of the rails there's just as much of a chance for bubbles getting past. With the regulator at the rear you don't have the hot fuel running back to the tank, aggravating the fuel bubble issue with the higher fuel temps. You're still bypassing fuel, and possibly bubbles, just at the rear of the car. Guarantee fuel temps in the tank and at the pump are lower than any system that bypasses from the engine compartment.

GM bypasses from the rear filter also, seems to be a non-issue for them. You probably won't get me to change what's worked for me for many years, the last ten years all forced induction builds. But I would like to know the theory or reasons why my way isn't good, because I definitely don't know everything, or even close. I'd appreciate your professional opinion.

Jody

[sacarguy]

I know you're an EFI guy and I'm just a hobbiest, so please explain how this is any different than running the regulator off the back side of the rails. Any bubbles still go through the rails first, right past (and into) the injectors. Even if regulated on the inlet side of the rails there's just as much of a chance for bubbles getting past. With the regulator at the rear you don't have the hot fuel running back to the tank, aggravating the fuel bubble issue with the higher fuel temps. You're still bypassing fuel, and possibly bubbles, just at the rear of the car. Guarantee fuel temps in the tank and at the pump are lower than any system that bypasses from the engine compartment.

GM bypasses from the rear filter also, seems to be a non-issue for them. You probably won't get me to change what's worked for me for many years, the last ten years all forced induction builds. But I would like to know the theory or reasons why my way isn't good, because I definitely don't know everything, or even close. I'd appreciate your professional opinion.

Jody


Very simple.. with the continual flow of fuel you dont get fuel boiling like you do with a dead head system with such a low volumed of fuel flowing through it you are far far more likely to have fuel boil vs the large volume thats being constantly flowed through a return style system.


The bubles usualy come from fuel being heated by exhaust etc and boiling in the lines.. properly insulated and routed lines can help this tremendously however bypasing in the rear also means for a slower reaction time to preasure drop

The preasure has to drop through the whole line all the way to the front before the regulator in the rear responds.. that could be a 8-10 percent drop in fuel preasure at the injectors themselfs while onlyh a 1-2 percent at the regulator.

either way works .. but the up front return regulator is more efecient at keeping a contant supply and preasure at the fuel injector as the distance the preasure has to drop over is very minimal before the regulator responds

This is why you will never see anything other then a return reg mounted very close to the fuel rail on a serious efi drag car.

Regardless 99 percent of people here will never make the kind of power that it would be a issue at..

and Yes I do specialize in fuel injected forced induction at my buisness. I just made 1600 rwhp on my turboed drag radial car last night.

[Pantera EFI]

I agree with the above pro's for "front" regulator.

ONE item not stated was the temperature of the fuel just after the injector.

"Cool Fuel", the lowest temperature fuel "after" the fuel passes threw the injector orfice will help keep the
cylinder from producing incorrect combustion.

Remember when a high pressure liquid (the fuel) passes across an orfice then into a lower pressure "gas"
the fuel expansion will extract heat from the gas. (inlet air)

Look at the fuel tank as one BIG fuel cooler, a "free" intercooler.

Lance

[DRJDVM's '69]

Where did you get the braided PS hose in black ??? Is that hose really rated to hold that kind of pressure ??

When I made mine a couple of years ago, the only ones I could find was Aeroquip hose and it only came in blue.... I'd love to change to black since all the rest of my hose is black.....the blue PS hose just looks out of place.

As for the regulator issue.....just like alot of "arguements" on here, on paper and in theory there is always a "best way" but often times that difference between the "best way" and option #2 is so small that 99% of the guys on here will never notice the difference or need to worry about it.

[sacarguy]

I also forgot to mention that in a efi system with boost you should always boost reference your regulator so that preasure rises at a 1 to 1 psi rate with boost preasure..

that can be a bit of a pain with a rear mounted regulator

the only exception to this would be a efi above a draw through blower since the injectors dont see boost against the pintle.

[XcYZ]

That's all good and I agree, but I'll be staying with the dead head setup.

[awr68]

That's all good and I agree, but I'll be staying with the dead head setup.

What, you don't like starting your day off with a trunk load of ice!?!? :lol:

[XcYZ]

LOL, I was thinking that very thing, Tony. It's funny that Lance should bring up fuel temps and the fuel system working like an intercooler.

I wonder where the infamous picture is.... :lol:

[awr68]

I think much of this would work well in race applications...but must of us are building street cars, so learning from the long haul crowd the dead head makes since.

[sacarguy]

itr works just as well in a daily driver better then a dead head for the same reasons mentioned .. its just your driver doesnt stress the fuel system enough for the dead heads short comings to show

its not that a dead head doesnt work its just that the other style works better.

you can use a dead head system just fine in a driver but the frotn mounted regulator is more efecient its a simple fact.

its like saying oh well a points ignition works just fine in my car

sure it does but theres no argueing against the advatnages of a electronic distributor

[Pantera EFI]

I believe that at the OEM level cost savings are REAL.

I believe that GM is able to CORRECTLY engineer a fuel system, then test is for years.

I know that the fuel pump can be PWM (Pulse Width Modulated), no regulator required.

Make ONE change in an OEM fuel system and you ask for trouble. (change=HP increase, etc.)

Lance

[sacarguy]

ahh but thats a tricky situation ther IS a regulator in the PWM system

its the closed loop between the ecu and the preasure sensor that tells the ecu to lower or increase pulse width

so in reality it still is a regulated system its just regulated by change of pump speed instead of bypassing the extra fuel.

pwm systems work well and can be reliable when setup right i personaly have the stock pwm returnless system in my 06 mustang and have made over 850 rear wheel horsepower with it via custom tuning and a larger heavier duty pwm pump driver module and replacing the single factory pump with dual pumps wich flow 310 litters per hour each.

I will be adding a third pump and another pump driver module now to supply enough fuel for a nitrous kit as well.

[awr68]

LOL, I was thinking that very thing, Tony. It's funny that Lance should bring up fuel temps and the fuel system working like an intercooler.

I wonder where the infamous picture is.... :lol:

Found them!! Ah the little things you will do to make it to the next stop!! :lol:
http://www.yenko.net/photos/data/548/medium/power_tour_2005_053.jpg
http://www.yenko.net/photos/data/548/medium/power_tour_2005_055.jpghttp://www.yenko.net/photos/data/548/medium/power_tour_2005_057.jpg

[ss dave]

Good Pics! LOL I went with a parrallel system as opposed to the dead end for several reasons. I'm running a modified LS7 with aftermarket fuel rails, 44.5 # injectors, Weldon reg., BG in-line heat sink cooler, in-tank Aeromotive A1000. The gurus at Kinsler helped with advice, check them out. Fuel delivery was important to my set-up. With a parrallel system fuel delivery is constant and consistent to all pistons, no vapor or decrease in pressure to lean out a piston. Easier to maintain fuel pressure. Lower temps due to circulation of the fuel. Cons are plumbling and costs. Nice car.

[Bowtieracing]

Cooler fuel?

If running regulator near tank, how about useing fluid cooler like this :

http://www.detroitspeed.com/images/Steering/ps_cooler_pic.jpg

Just as long as possible close to frame rail ???

[thedugan]

Those pictures look like the Jody solution from Power Tour .. am I right?

Barry Grant also sells a fuel cooler, which comes with AN female fittings.

My understanding also is that the boost reference line has to be a few feet from the manifold pressure. It will not work if you run a line front to rear and connect to your rear mounted regulator.