Fuel lines, hard or soft. What is the general sense on fuel lines?

Fuel lines, hard or soft. What is the general sense on fuel lines?


What is the general sense on fuel lines?

What are folks running over stock. [say stock lines are all bad]

I believe 3/8" is good up to around 500hp no?

What kind of line?

soft
rubber
steel braided rubber.
steel braided teflon.
teflon braided rubber.

Solid
Copper.
Aluminum.
Galvanized Zinc.
Stainless steel.
Other

What kind of fittings.

AN - aluminum
NPT - brass

hose barbs n clamps?

 

Thinking of pulling the trigger on this kit. Around $45 shipped.
Could get similar without any fitting for $26 shipped.

Also pick up a brass T fitting for a FP gauge.
And a $20 0-15psi FP gauge. [jegs brand]







http://www.jegs.com/i/JEGS/555/63036/10002/-1

The Original Heavy Duty- Plated Tubing
Heavy duty original equipment type double wall copperized steel tubing which is coated in galvanized zinc for superior rust protection.

Each kit includes 25' of tubing and an assortment of standard inverted flare fittings for domestic vehicle applications.

JEGS #555-63036
Fuel Line Coil Kit

Galvanized Zinc
3/8'' O.D. Tubing Kit
$33.99

 

3/8" OD tubing (about 5/16" ID) might not be quite up to snuff for that level unless you have a serious pump for delivery; if you project needing lots of volume you might consider upsizing so you don't have to do it again another day.

3/8" ID flexible hose would probably be fine for that level with a mid-range electric pump or high-vol mechanical. The drawback to flexible hose is that it doesn't resist abrasion or heat as well as metal lines, unless you really step up with the dollars for braided stainless reinforced hose for abrasion resistance. The braided hose is expensive and could be run for the entire system back to front, but be warned that the stainless braid is so tough that if it comes in contact with other components, it usually wins...I sold a recall solution years ago by rubber-coating the braid because it was rubbing on transmission cases and causing leaks...not fuel, but tranny fluid!

In the OEM I run hard line (the double-wall tubing you mentioned is very good stuff) for as much rigid distance as possible. Don't let it touch or rub any hard surface unless it's going through a plastic clip or rubber-lined metal P-clip. For a high performance application, stainless braided line rules for jumping to moving parts (engine) or if you have joints that have to be serviced, like fuel filters...if you can afford it and the AN fittings.

Flexible rubber hose is fine for the dynamic parts too. I try to minimize rubber hose as much as I can. Use good stainless worm drive clamps (double clamp with screws 180° apart when possible), and put at least an end bead on the hard line to help improve rubber hose pull-off effort. Barbed fittings help with this, too. Hard line will always win the heat war. Rubber and stainless braided Teflon hose will lose the heat war...even the high dollar stainless might look fine on the outside, but the Teflon on the inside can't handle it. You don't want to rely on fuel as a coolant for your lines.

Inverted flare, NPT and AN fittings are all suitable for our fuel system stuff (use pipe dope on NPT, not Teflon tape).

And hey if you have specific questions don't hesitate to ask...glad to help if I can.

Devon

 

Would the stock sending unti be a bottle neck? Its 3/8" feed???

 

Very well might be. The fuel has to manage the ~5/16" ID, plus they usually have a "sock" at the pickup point that stops tank debris from moving forward. The sock can get pretty plugged up over the years.

I think there are suppliers for a high-vol pickup for the Skylark/GS cars at least, don't know if that helps you. I think it's RobbMC, maybe TA too? Haven't had to try one so I just remember reading about them.

Devon

 

the rule i have always been told is use metal. use high quality rubber in short length. like frame to pump where vibrations wreck the metal connections. jim

 

That was the plan, I got some good 3/8" stainless braided rubber already but only a few ft.

 

what are you running? if its just a mild sbb, stock lines will be fine. all im running on mine. just make sure to keep it away from exhaust if you use rubber. i used some braided line up along firewall,to the regulatormost race tracks dont want to see a lot of rubber around engine compartment

 

Matt asked about a 500 hp target; the displacement of the engine is pretty much irrelevant.

I'm not up to speed on the latest NHRA regs, but it used to be you were allowed 12" of rubber line...not much to go on.

Devon

 

Slick setup.

I run stainless quick connect fittings at both ends of my braided fuel & trans cooler lines, but then they were "off the shelf" items for me at the time.

Devon

 

I tossed and turned all night thinking about these fuel lines.
Never got any good sleep, folks kept grabbing all the fittings before I could or something then I was awake. Over n over all night.

Quick disconnect sounds neat but ill assume you dont mean normal air fitting stuff??? Would need to be ubar fancy to flow ehy???


On some things I will spend the money to plan ahead. You wont see me spending $5000 on bodywork but anything that can be moved with the engine and trans to another car that breeds performance is a good thing.


I can get 25' of 1/2" almuinum cheap but will that fit the size of fittings used for the fuel pump and carb?

Would I have to step it back down with a fitting at the FP and carb connections?

Or just run 1/2" from tank to FP then let it step back down to 3/8" like stock?



BTW summit is having some good sales on all that stuff right now, prices are slashed nice.

 

The quick-connects are OEM fittings and are crimped to the end of my stainless braided lines; not off the shelf stuff for most people. =If I had 1/2" aluminum tubing available at the time I would have used it myself, but instead I have twin -06 rubber-coated braided lines running from back to front. It was just convenient at the time.

Your q-jet inlet is sized for 3/8" OD metal tubing w/SAE 90° flare. It's no problem to run ovrsize 1/2" OD tubing for the majority of the back-to-front plumbing and step down at the ends as required. Every bend in the tubing adds restriction, so using larger diameters helps offset this. A good rule of thumb when bending hard line is to use the largest radii possible...don't make tight bends unless absolutely necessary, and use a tubing bender that supports the tube all the way around so it doesn't collapse on the inside of the radius.

Devon

 

Im a bit ready for over kill as I don't wanna do it all then still have problems.
And right now 1/2" aluminum line is cheaper by allot.

Why I will also drop the tank and inspect n mod all.

But Im trying to get everything worked out ahead of time as the Buick is my only reliable transportation right now.

 

My friend that builds Robbie Gordon's off road cars really likes the Twist-Lok hoses. As I understand it they are NHRA legal.

I also like doing AN hard lines. I use the Al lines for fuel. Aluminum is very durable if you support it properly and do not let it rub anything. I had a friend of mine modify a cheap 45* flare tool for 37*. Make sure you put the tube nut and sleeve on before you flare the end (ask me how I know :laugh: )

I use braided stainless for super critical components that need some flex. Teflon braided for the high pressure power steering and the oil feed for the procharger. Same for the fuel pressure gauge.