Brake and Fuel line size?

[jeffball610]

I'd like to run as much hard line as I can to keep it clean. I know I need a good size line to feed my hungry turbo motor. I would like to run -6 or -8 braided lines for fuel, but what does that translate into for hard lines? Should I run standard steel, aluminum or stainless tubing? What size line do I need for my brakes? I'm running Toyota 4 pistons up front and 200SX disks in the rear with a 280ZX 15/16" MC. Any idea about how much line I'll need to order?

In case you're asking why do I need all new lines, I'm swapping in a motor (4G63T) with the intake and exhaust switched from the Nissan norm. The fuel line needs to be away from the hot exhaust. (duh) Besides, who wants to run 35 year old brakes lines with who knows what inside them?

[Cmac]

3/8 OD fuel line one for feed and one for return.
3/16 OD brake line

The choice is yours depending on your budget. Stainless line will cost you about 4 dollars per foot plus the fittings. I am unsure as to what the other lines will cost.

[S15DET]

I 2nd Cmac's recommendations for line sizes. The only think I'll add is that you should stay away from aluminum fuel line when dealing with EFI fuel pressures. Aluminum should only be used for low-pressure carb. applications.

Oh, and 1/4" (-4N)for the clutch line.

[RWD_NissanMan]

The only think I'll add is that you should stay away from aluminum fuel line when dealing with EFI fuel pressures. Aluminum should only be used for low-pressure carb. applications.

Where did you hear this & why?? I've always used aluminum fuel lines in all my EFI cars and never had any issues.

[S15DET]

Probably Carroll Smith, and I think that there was a note about this on one of the sites that sells racecar plumbing.

[RWD_NissanMan]

I asked the question of the EFI tech. support specialist for Russell. Here is the reply I received.

"I am not sure why some people would say Aluminum will not work other than it is very soft. It usually comes in rolls so it does not require a special bending tool to make it conform to your vehicles outline, but it is not as good as stainless hard-line which does require special bending tools to not collapse it when bending. I would not use it as stainless hard-line is much better although more expensive."

I found another note on a web site that indicates aluminum fuel lines in EFI applications should not be used due to problems with "fittings". http://www.competitionengineering.com/c ... Code=10158

NOTE: NOT FOR USE WITH HIGH PRESSURE FUEL INJECTION BECAUSE FITTINGS CANNOT BE INSTALLED PROPERLY.

I think this stems from some people not using it with the proper 37 degree JIC flaring tools and proper aluminum tubing sleeves and flare nuts. I assume that most "back yard" mechanics might not have a JIC flaring tool or overtighten the nuts which could damage the softer aluminum this leading to problems. If coupling to aluminum AN fittings and by using a decent flaring tool, I find it is really easy to work with and produces nice, lightweight results. As I mentioned before, I have never had a problem when using aluminum to plumb an EFI system. The aluminum fuel line you buy from Summit or Russell, etc. is seamless, sized by the OD and has a pressure rating of 250psi.

[RWD_NissanMan]

Here's another comment I found.

"The main issue when dealing with aluminum tubing (or any aluminum for that matter) is that it “work hardens” when it flexes, which can lead to cracks. It is important that the hard line is isolated from vibration and movement.

Clamp the tubing securely with rubber coated clamps (Adel clamps) and use bulkhead fittings where the tubing attaches to the flex line. Never run the tubing directly to the engine without a flexible hose section. If installed properly, aluminum tubing is safe and durable."

[jeffball610]

With the minor price difference between SS and aluminum, I think I'll go with SS. I understand I'll need a bending tool and flare tool and I know I can pick these up from the tubing supply source. (Summit, Jeg's, etc.) When dealing with the fittings, what am I looking for. I know there are standard "line nuts" etc., but what else? I know that I'll need something to adapt the hard line fitting to AN fitting for soft fuel lines. Is there anything special that I'll need to connect SS braided brake lines to the hard lines? OE lines seem to have a variety of weird fittings and connections to the soft lines. I'm sure I'll learn more when I start gathering parts and see what I'm missing, but thought I'd get some advice here.

[RWD_NissanMan]

Can't speak to the adapters you'll need because I don't know what components of the fuel system you are using. To make life simple, I have always converted everything over to standard AN fittings - for the fuel system something like 6AN (6/16" = 3/8" tubing). Most common adapters are NPT taper or straights (some FP regulators and pumps such as Aeromotive use straight threads and require the adapters with rubber "O" rings to seal the adapter to the body of the regulator).

[wilderb]

check ebay for 3/8 stainless tubing, I got 25' for $50 shipped that equates to about $2 a foot

[johnbureezu]

Why is it that the guys doing my fourlink are so weary about using stainless line? When I brought it to him he looked like he seen a ghost or something. He mentioned that it super hard to flare and bend w/o breaking it. How much and where can I get the JIC flare tool? AHHHHH... may have to just go the steel route/

[Byron510]

John,

There's no need to back down from the stainless line. I did my whole car - so 80 plus fittings - and only had to re-do ONE of them! I used a Ridgid 37 degree flaring tool, and standard steel hydraulic fittings. The stainless line bent beautifully with a standard brake line tool for the 3/16" line, and I bought a more rugged purpose built proper industrial 3/8 tube bender for the fuel lines (you’ll need this by the way).
Who ever told you that it can't be done, just probably doesn't have the right tools to do the job in the first place. I used 316L SS for all my lines. I would have liked to use stainless fittings as well, but the cost was really high. I think I spent $500 on the steel fittings as it was. There are a lot of fittings in a whole car if you plumb it properly, using bulk head fittings at each metal panel, and I also used bulk head fittings at each tube terminus as this allowed me to place a bracket at that spot to secure the lines properly.
It can be done, and is done all the time. But you will need the right tools. I paid over $300 for the Ridgid flaring tool, and it was worth every penny. A cheap flaring tool just wastes tubing and your time - and that gets expensive real fast when using stainless steel.
Byron

[johnbureezu]

Yeah Byron,
They don't have the tool to flare it so I may have to buy it or if I can, find somebody local to lend it to me. I would really like to keep it all stainless if I can. $$$ is also an issue.
Is this the tool in question?
http://www.ridgid.com/Tools/458R-Ratche ... /index.htm

Thanks for the help Byron

[Byron510]

Yep that's it.

Cat # 41162
It's a beautiful tool, with a built in clutch so get a perfect flare every time.
Let me know what you paid for it. I know I paid way too much. But as usual, when I'm working on something, I tend to buy what's at hand to make the job easier. I used my company’s supplier as I found no other local one that had stock at the time. When you post your $$$ amount, I'll probably fall off my chair - but I'll be ready for it!

Byron

[Derek]

I will attest to the quality of Bryon's tools as I borrowed them to do my stainless hard fuel lines (thanks Byron!!). I wasn't as good at it though and a couple of tiny weeping leaks formed where the hard line met up with the bulkhead fitting. I ended up fixing them with some of these: http://www.flaretite.com/prd.asp and it's been good ever since.

You can see my plumbing story here: http://www.the510realm.com/phpBB3/viewt ... a&start=75