LS swap fuel line ??

[Cheeseman]

I have the new tank mounted and the motor in place and am ready to run fuel lines. I have an 02 LS out of a Tahoe and it has the dual line set up with the return coming from the rails. I have found the proper fittings to go to AN and quick locks on the rail, but I am reading up about the push lock type fittings that are to me no more than a pushed in babred fitting. From what I have read it takes the special hose to work with those special fittings. Any pros, cons or experienced opinions on using this set up or should I just go with the old trusty AN type screw down fittings and line? Also, do I need to run high pressure line for the return line as well or can it be just regular fuel line?

Thanks for any and all help!

Cheese "getting this thing closer to firing up!" Man

[truckdude239]

stay away from plain rubber line i'm running summits 6an teflon braided hose good up too 100psi

[Cheeseman]

is that what you are running on your pressure and return lines both?

[truckdude239]

both

[BigDan3131]

When I was figuring it all out a while ago the push-lock fitting cost a little bit more than the AN stuff for high quality fittings that is and it was about ten percent more overall for push-lock. If you were trying to save weight then yes I would use them, my uncle ran all of his lines with them.
All of my AN stuff is either KB or Aeroquip.

[Blackpony]

I used fragola brand fittings with summit brand stainless lines front to back feed and return lines then put a Russell brand 10 micron filter after the pump all with an fittings. 0 problems and it looks great
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[Robznob11]

i went to the salvage yard and cut the ends off donor trucks i left about 6" of steel line. Then i went to auto zone and paied 20$ for a roll of coated 3/8 steel fuel line and borrowed there double flare tool. Then i just used brass compression fitings to put it all together. By the way napa sells fuel injection fuel line, special clamps, and the push lock ends if you cant get doner ends. But use as little rubber as possible
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[68c10airstream]

Hi Cheeseman, when i installed my 5.3 in my 68c10 i used the organ donor quick disconnect fittings with the stock rubber lines. I have the hydraulic flaring tool from mastercool so i made oring style fittings for a stock gm fuel filter, edelmann brand of fittings that are slid into the organ donor rubber lines. The edelmann brass fittings have a flared end so the rubber lines can't slide off. The other end of the edelmann used inverted flair (brake line). I have a friend with a drag car with AN fittings and complains steady of fuel leaks. As a past ase master mechanic of 30 years i look at it this way, gm engineers had a gun to their head to design a fuel system that didn't leak fuel (fire hazard and emissions violation) needs to be safe in a collision, handle high pressure, etc, etc,. I figure a room full of gm engineers is better that delicate aluminum fittings that obviously have the tendency to leak, need special aluminum wrenches, costly, etc. In my 30 years i never saw a single fuel leak from inferior designed parts, only leaks from the ravages or salt. Ford uses a lot of stainless in their fuel lines at times. My opinions will most likely stir the pot but in my world of 30 years i wont be using AN fittings. Good luck Brian F.

[BR3W CITY]

So you think the engineers behind the Military and Industrial standard 37* JIC flare thats used in AN, were inferior to the guys that re-designed gm fuel systems in the late 90's?
I don't follow the logic, though I do understand what you are trying to say.

I can't say that the auto industry has always done things because its the BEST way...simply the BEST way that fit into the budget, time and homologation concerns.

The costs to run stainless/nylon braided lines or PTFE would always be higher than running thousands of feet of bent steel and rubber lines.

Aluminum AN fittings are a high performance part, and the assumption of certain maintenance concerns go with it. The correct tools help (though i think 70% of us don't buy the aluminum wrenches), but overtightening of the aluminum, incorrect termination and assembly of the lines, and the improper use of threadlocker/tef products/sealers all contribute to these failures.

And I don't like getting turned away from NHRA tracks for having more than 12" of rubber.

[Cheeseman]

All great info guys, keep it coming. I did receive all the donor fuel lines to the tank so I do have the filter, brackets etc. I am having a hard time finding info on what the size/thread pitch is on my blazer sending unit/fuel pick up assembly. I may have to pull it out and bring it to the parts store to get that figured out. I am leaning towards the steel line and double flaring set up. Since I have the factory fttings on the rail, I am thinging that I can retain those and keep it a pseudo factory look to the motor. The rolling chasis is supposed to be transported to the body shop this week to get the cab placed on it so I was trying to tie up the loose ends and make it easier to put the fuel lines in while the cab was off.