Help me set up a fuel system

[fasterpatrick]

All right I'm not going to experiment with this so, I need some guidance. You guys have traveled this road and why reinvent the wheel. So here is what I got One low mile 93 Mark VIII engine, this will remain stock for the most part, summit fuel cell, and not much else. I'm starting with nothing, want after market fuel rails, need external fuel pump, filter and regulator. Will run return style system, this does not need to be rated for over 400hp since I have no plans to ever take the motor there, the car will only weigh about 2000lbs, so I don't need to. what would you all use for lines, pumps, fittings, filters, and regulators. Any hints for laying it all out are helpful as well. All right guys lets get those ideas coming. Oh here is where I'm at with the chassis I have to start thinking about laying in the ground work for the fuel system soon.

http://www.clubcobra.com/photopost/data/500/IM001197_Small_.JPG

There's lots more pics in the link at the bottom.

Patrick

[brans72]

good ? to ask for anybody! i will be watching this also for recomm on my own chevelle. sweet looking beast you got there by the way!!!:thumbsup:

[64duece]

When designing a fuel system, I go by the "30% Rule" When pumps are tested and rated they include specs for voltage vs. pressure. They don't account for g-force and inlet/outlet restrictions and plumbing decisions.

I would look to run hard feed and return lines attached to the frame and protected as best as possible. At the engine area, you'd want to switch to a short flexible line for chassis to engine coupling. The best advice I can offer is to use quality 100 micron pre and 10 micron post filter. I'd look at a Walbro GSL392 inline 255lph pump mounted in a gravity position as to induce good inlet flow.

The rails can be done with a less expensive rail mount regulator like Holley's 512-500 attached to a set of their universal rail kit like 534-79 machined to fit your application. You can also run a remote mounted regulator which is abit more expensive along with the addtional cost of fittings. We also have to take our customer's budget and needs into the plan. Hope this helps

[fasterpatrick]

Now here is where I'm about as dumb as a box of rocks. I will be plumbing my fuel system for my stock Mark VIII 4.6l from scratch. Everything from tank to rails is aftermarket, so I will not need to incorperate any stock parts into the system. Which of the following diagrams would you chose to plumb this system? (Thanks Wayne for the illustration.)
http://www.ffcobra.com/photopost/data/500/medium/VCPFuel.jpg
Now version A & B look rather simple but I worry about fuel not being able to get evenly to all the injectors, am I off base here. Version C seems like the last in line might get hungry when you push the loud pedal. Version D looks the best but I really don't want all those hoses under the hood if I don't need them. Man I suck when it comes to this stuff someone please help.
Patrick

[Kendall Burleson]

The best set up in your illustration is version C. This system takes in consideration the full pressure that the system must operate when in use.By having the regulator positioned at the end of the fuel rail it will control all injectors evenly and handle demand properly.For example,if the regulator is set at 50psi. everything from the regulator back to the fuel pump is held to that pressure. Any pressure above that amount is bled off threw the return line back to the tank.My version differs a little bit but may fit into your budget a little nicer.Contact me through Lateral G pm. Thanks Ed.

[camcojb]

I've run Version B in several cars to way past 800 rwhp, no issues.

Jody

[Vegas69]

Go with what works and is proven. I've seen Jody talk about fuel heating issues with C. I like B for a fuel injected set up and A for a carb setup. On a drag car C.

[The WidowMaker]

im not an expert, but im running either a or b with the regulator right next to the tank. no use pumping the fuel way forward to an engine mounted regulator and then back. it adds too much heat.

[The WidowMaker]

this is actually what im thinking about doing. i drew it up with no consideration to where the parts and pieces will acutally go. placement is more for the ease of viewing.

http://www.fquick.com/images/vehicles/full/23712238092.jpg?1235941839

im not sure why the image isnt showing..... im using the format like every other forum??????????

Tim

[fasterpatrick]

Well, I have received the major components for my fuel system still need to order line and fittings. I think will have to plumb a new fitting into the bottom of the tank for the pick up or do you think the fuel pump would draw fuel the whole 12" that the tank is high. my thought was to mount the pump below the tank and hope the the siphon theory would help draw fuel to the pump.
http://www.ffcobra.com/photopost/data/500/medium/IM001215_Small_.JPG
http://www.clubcobra.com/photopost/data/500/IM000907_Small_.JPG
I hope these pictures help explain my situation and how I'm going about this project.
Patrick

[Pantera EFI]

I worked on "Lone Star".
I have raced many Cobras.

I agree with the above statements, though I might add a "make-up" tank.

This item is used for racing, to provide the EFI pump with fuel under high "G's".

A/two lift pump(s) are used the get the fuel from the cell into a fuel reservoir that will feed your pre-filter.

The make-up tank has a return into the main tank from the top that allows air to escape from the fuel.

Lance

[camcojb]

I worked on "Lone Star".
I have raced many Cobras.

I agree with the above statements, though I might add a "make-up" tank.

This item is used for racing, to provide the EFI pump with fuel under high "G's".

A/two lift pump(s) are used the get the fuel from the cell into a fuel reservoir that will feed your pre-filter.

The make-up tank has a return into the main tank from the top that allows air to escape from the fuel.

Lance

yep, a surge tank. Works great especially on a road course car.

Jody

[peetsjunkie]

I've run Version B in several cars to way past 800 rwhp, no issues.

Jody

What type of setup did you have?

I'm in the same boat here with EFI fuel system planning. The FAST fuel system design is just like "D". This requies lots of lines and fittings all over the place. I'd like to keep it clean if possible, so B or C look to be the best.

[camcojb]

What type of setup did you have?

I'm in the same boat here with EFI fuel system planning. The FAST fuel system design is just like "D". This requies lots of lines and fittings all over the place. I'd like to keep it clean if possible, so B or C look to be the best.

#10 line out of tank to 100 micron pre-filter, to pump to regulator to 1/2" hardline to front of car with 10 micron filter inline. Pre-filter, pump, and regulator are all at the rear of the car close to the tank. A high-flow "Y" at the rear of the motor with (2) #8 lines to rails. I added a crossover line to balance the rails at the front, but have run without it.

http://www.camcojb.com/temp/malitude 303.jpg


http://www.camcojb.com/temp/malitude 305.jpg

Jody

[peetsjunkie]

#10 line out of tank to 100 micron pre-filter, to pump to regulator to 1/2" hardline to front of car with 10 micron filter inline. Pre-filter, pump, and regulator are all at the rear of the car close to the tank. A high-flow "Y" at the rear of the motor with (2) #8 lines to rails. I added a crossover line to balance the rails at the front, but have run without it.

Jody

Wow that is close to the pipes....Well I guess I'll have a change of plans then based on this design. That's pretty slick there .... :hail:

Any issues with runnning such a short return vs a long return? Wouldn't a long return help cool the excess fuel to go back into the tank?

[camcojb]

Wow that is close to the pipes....Well I guess I'll have a change of plans then based on this design. That's pretty slick there .... :hail:

Any issues with runnning such a short return vs a long return? Wouldn't a long return help cool the excess fuel to go back into the tank?

it's not near as close as it looks in that pic; probably 3-4" at closest, and I have the fire sleeve for insulation.

No issues with the short return for me; light years cooler than a front mounted regulator after the rails, with the super hot fuel coming back after being heated by the rails and engine compartment.

Jody