EFI stainless steel hardline project
 

I got the bug to take on ditching my braided ss lines for hardlines. Will be running a 5/8 feed and a 1/2 return. Bought imperial eastman benders and a Ridgid 37* flaring tool.

My q's are will. 035 wall seamless annealed ss tube work for both of my sizes? The 1/2 bender has a 1.5" radius and the 5/8 bender has a 2.25" radius.

Are there issues using aluminium tube nuts, sleeves and fittings with the ss ine?

I think the .035 wall tube will be fine... but you might want to consider aluminum tube, rather than SS. Aluminum has a bunch of advantages:

1. Lighter
2. Easier to bend
3. Conforms better to seal surfaces, so it leaks less
4. Has a higher coefficient of heat transfer (mu), so heat in the gas can radiate

Some dislike aluminum due to its lower strength and the notion that it can be "punctured" from road debris, or because of a worry about work hardening.

All these issues are valid to some degree, but aluminum has plenty of strength for fuel pressure, and has less of an issue with work hardening than SS. I'll leave it to you to consider the odds of a rock hitting your aluminum fuel tube and causing it to leak, but not so hard that a SS line wouldn't leak too. I think those odds are extraordinarily low... but it's not zero.

Doea aluminum need to be double flared?

No. Use 37* flares (AN / JIC) with sleeves and nuts.

Who makes the nice billet mounts that hold 1/2 and 5/8?

<----- JCG or Ironworks maybe?

I'll second aluminum over SS. The SS is a pain to bend and flair. If you are worried about damage to the aluminum fuel line, it's easy to make good looking covers to hide the more exposed sections. Also, take in to account the route you take from tank to engine. It doesn't have to follow the factory routing. The more protected the fuel lines the better no matter what material you choose to utilize. Good luck.

Here is a thread on Stainless Steel tube bending.. Mark from www.bentcustomandperformance.com started the thread, so you might want look at it.

https://lateral-g.net/forums/showthread.php4?t=28726

Jeff

Just curious why you are running those sizes?

I have run this configuration in braided ss for years with great success. Im really afraid to make a change at the risk of damaging my combo. This is a supercharged engine making approximately 1100-1200 hp. Using a magna fuel 750 protuner pump.

What wall thickness do you use jp?

Fair enough but fwiw I've made 1100+rwhp on several occasions with efi and a 3/8 feed line.

I wouldn't bother trying to fit a 5/8 feed with EFI unless I was aiming for 3000+hp.

Understood if you don't want to change it but just thought I would mention that it's way overkill.

I use .035 wall tube. I used to buy 16 foot lengths, but now I can only buy 6' lengths. The really soft aluminum coils you can get at Summit work fine too, but straightening it can be difficult.

I set the braided system up on advise from Aeromotive years ago. Its a 10 feed and 8 return, would this equate to 5/8 and 1/2 hardline? Magnafuel recommends the same -10 feed and-8 return for my combo in ss braided. Are size requirements less for hardline??

Just to make sure were on the same page the 1/2 and 5/8 are OD sizes.

You are correct on the size correlation, (-10 being 5/8 and -8 being 1/2).

The size requirements are not less for hard line.

Not sure why both of those companies recommended that size, would only make sense to me if it was a low pressure carbureted system. (what would they recommend for that, -20?)

The cars with the 3/8 feed line were 4th generation f-body's with the stock fuel feed line (3/8 OD) at 1100+rwhp, so even if you went -8 feed it would be overkill.

Again, do whatever you feel comfortable with, just sharing my experience that you can easily meet your goals with much less feed line.

Thanks for the input, i have always wondered if i could choke the lines down. Lets hear a little more on the combo, ie cubes, power adder, fuel pump, injectors etc...Big wheel HP makes them sound cool already!

A few were 402-408ci LS motors with twin 67mm turbos, 1150rwhp.

One was 370ci and ran 8.30's at 165mph in the 1/4.

Most were twin walbros with a boost a pump and 96-120lb/hr injectors and stock 3/8 feed line.

We do have one car with a -10 feed line that runs 205mph in the 1/4. At 3215lbs that's around 2000hp.

(I work for a shop that specializes in turbo LS setups)