Hi everyone, I’m trying to replace my stock fuel lines with AN lines, from the sending unit all the way to the fuel rail. I need to know the size of the fittings on the feed and return lines on the fuel rail and sending unit.

 

3/8 feed 5/16 return. If your retaining the stock saginaw witting on the tank sender
fragola and earls sells a saginaw to an6 fitting.

 

Thank you for the reply! Do you happen to have the exact part number for both? There’s so many options on summit I want to make sure I get the right ones the first time.

 

Fragola 491970 and 491971
491963 and earl's 9894DBJERL

 

Just curious are you replacing the hardline from 3/8 to an6 ? Or just the high pressure flex hoses ? 3/8 is an6

 

I’m replacing the hardline from the sending unit to the fuel rail, feed and return, with an6 or an8. I have the car gutted and it will eventually have a 383 stealth ram on nitrous with e85 within a year or so, so I want to have plenty of fuel line.

 

6an for the feed and return will be fine. When I did my fuel system I used an aeromotive stealth setup. Aeromotive said 6an was sufficient up to 650 hp w forced induction and higher without. Just make sure you have sufficient return. Otherwise you'll have fuel pressure issues and potentially fuel pump issues.

 

Did you keep the stock sending unit lines then adapt it to 6an? If so did it work good?

 

Nope, I used a full aeromotive stealth unit

 

Is that the entire fuel tank kit or just the pump and sending unit assembly?

 

I used the tank+sender combo. I figured my original 82 tank was gonna be a mess. It was totally fine inside and out so I could have gotten away w just the sender. In the end I'm glad I did both. Just one less thing to replace later. Dropping the tanks sucks. I'd rather do an engine than the tank.

 

Yea I understand completely, more than likely what I’ll be doing. Do you happen to know how much total 6an line you used? Like how many feet around about?

 

Odd timing for this thread, I just finished putting in a new tank, sender, and converted it to AN fittings this morning. I used the metric O ring to AN adapter for the send line and then flared the rest of the sender lines. I then used flare nut to AN adapters for them. I'm keeping most of the hardline, I just wanted to get rid of the nasty rubber hoses and crusty lines at the back of the car. It's a pretty miserable endeavor, ended up dropping the rear end on my finger early on in the battle so I've been doing it handicapped lol

 

These work great with the stock sending unit to convert to AN fittings. Just cut those other fittings off and put these on

https://www.racetronix.biz/p/adapter...lack/adf-8hl38

https://www.racetronix.biz/p/adapter...ack/adf-6hl516

 

Get teflon lines, not rubber. Rubber can bleed fuel vapors out and stink up the garage.

I've been running teflon lines since 2008 with no issues. Just use plenty of heat shielding anywhere the lines get even remotely close to exhaust pipes.

 

Oh yea I’m using ptfe line. Gonna use it for my transmission cooler lines too.

 

Not to completely hijack the thread but do you all think it's worth swapping the entire fuel line all the way back to 6AN or use the hard lines in the middle and just the AN lines at the pump/fuel rail?

 

I'd say it would depend on just how technical you wanted to get. There's less fittings to use if you went front to back with AN lines.

 

Off the top of my head, feed and return lines from the regulator that I installed (84 so didn't have one initially), then feed all the way to the rail?

The only reason I ask is because my fuel lines still have barbed fittings and I'd need to cut and flare to make the compression fittings and adapters work.

 

Yeah just more connections. Every connection is a possibile risk for leak.

On my 2nd gen when I converted to EFI, I also went tank to rail with AN line and have been running it that way for damn near 30 years now.

 

The way I did my system was a made a little drawing from sender to the rails and figured out everything I needed. I cut those long lines off of my sender and used compression fittings then AN lines all the way to the front. I Y and feed both rails from the front and exit to the regulator then a -6an return

 

Another thing to consider is how do you want to feed the rails?? Do you want to use a single feed then crossover, regulator and return. Or single feed then Y block into two feed lines to both rails and exit both rails into the regulator and a single return line??

 

I have a 4th gen tank with a herko sender. I removed the built-in regulator at the pump and was going to use the Corvette filter/regulator installed down on the frame where the factory regulator/filter was on the later FI 3rd gens. Then run a single feed line to the front with a cross over at back of the fuel rail.

On the carb cars, the hard line runs up to the trans, then over the trans tunnel and comes out on the passenger side.

 

You'd be better off having a fuel rail mounted regulator and not bother with those Corvette style filter/regulator combos I've been hearing a lot of bad stuff about them lately. Mainly them having sky high pressure.

 

Well, I already have the regulator and it would keep me from running a return line from the front of the car.

Not sure if I posted, this is for an LS1 Swap.

 

I’d also say it also depends on what shape your hard lines are in and also if you’re wanting to go way up in power. Hence why I’m doing ptfe 6an lines front to back due to pinhole in the pressure line and eventually having a nitrous e85 383. Want to have plenty of fuel flow and everything be less complicated. Can also reroute fuel filter in engine bay for easy change.

 

Been doing some more reading while posting this thread. I think ya'll are starting to make sense to install PTFE lines front to back and just bypass/remove the original 40 year old fuel lines.

 

My entire system is -8/-6 feed/return PTFE. It costs a little more but totally worth it

 

would like to know as well.

I bought 2 oem style 3/8 feed lines but trying to adapt that to work to my aeromotive sending unit and holley FI system has me really considering throwing all that in the garbage and just doing one continuous run of AN line.

 

Both my feed and return line were damaged, so I went with all new -6AN PTFE, and it was a much simpler setup. I also swapped to a 4th gen tank which really made it easier.

 

What are you running for a filter/regulator?

 

I'd like to put a plastic 4th gen tank into my car as well. Then I could drop in a sender with dual 450 or 525 pumps.

 

@Ozz1967 I am running the factory regulator on the rail still.

 

ok, originally carbed so no factory regulator. Planned on using vette regulator but reading some people having issues with them