Stock fuel lines too small?
12-11-2005, 05:26 PM
#1
TECH Enthusiast
Thread Starter
iTrader: (17)
Join Date: Sep 2005
Location: Detroit, MI - Camp Pendleton, CA
Posts: 619
Likes: 0
Received 0 Likes
on
0 Posts
Stock fuel lines too small? I just bought my LS1 swap yesterday. Its going into a 240sx S13 model. I am curious as to whether the stock fuel lines will work with the swap. My plans are to use a upgraded Walbro 225 LPH pump with the stock fuel lines and connect accordingly from the engine bay fuel filter to fuel rail via Steel braided line. I am concern with the stock fuel lines not flowing enough volume and possibly leaning the engine out. I will have to check but I believe that the stock steel fuel lines from the in tank pump to filter is about 3/8". If that isn't big enough then my next move will be an external pump with -6 AN line. I just want to avoid any extra work if possible. Thanks guys!
-Alex
-Alex
12-12-2005, 10:21 AM
#2
Fuel line... Alex, if you do indeed have 3/8" inch I.D.(inside diameter) fuel line already in the car, that came from the factory, and are routed the way you need them, then, yes...they are very usable. 3/8" is what the fuel supply line calls for on a stock or modified LS1 up to...say 450 h.p. or so. Steel AN female couplers can be bought at your local hydraulic hose supplier. You simply slide them over the end of the steel tubing & flare the end of the tubing with a flaring tool. You can then adapt any type of hose or fitting to that end now. 5/16" i.d. is the return line diameter. In AN sizing: 3/8"= -6AN...5/16"= -5AN hose & fittings. AN specifications were created by the Army & Navy for the militaries use, thus the term "AN". In fact, most of all the nuts, bolts, thread sizing, & most other hardware sizing was created by our government for use in WWll, as previous to this there was no "standard" size anything that exsisted. When something broke in the field, they did'nt know what part(s) to send to fix it, prior to this standarization. Hope this helps. Gar
12-12-2005, 10:47 AM
#3
TECH Enthusiast
Thread Starter
iTrader: (17)
Join Date: Sep 2005
Location: Detroit, MI - Camp Pendleton, CA
Posts: 619
Likes: 0
Received 0 Likes
on
0 Posts
EXACTLY what I needed to know. Time to get on summit and get some lines. Do you know if the highflow 255 LPH pump will be sufficient enough for fuel supply? Thanks Gar!
-Alex
-Alex
12-12-2005, 12:29 PM
#4
Staging Lane
iTrader: (3)
Join Date: Dec 2005
Location: Chicago/Champaign
Posts: 99
Likes: 0
Received 0 Likes
on
0 Posts
plenty. unless you are going to get crazy with the motor. i know FD's have trouble under hard acceleration with the fuel in the tank getting pushed to one end and not being able to get pumped into the motor. i assume a similiar problem may occur with a 240. if you're not keeping small amounts of fuel in the tank for racing purposes, it should be ok. just dont run it close to empty.
12-12-2005, 10:43 PM
#5
On The Tree
Join Date: Apr 2005
Location: S. Philly
Posts: 192
Likes: 0
Received 0 Likes
on
0 Posts
holly cow. Thank you very much Gar. You've just saved my day. I've been looking for the info about the AN fittings and sizings so I can buy parts to finish my fuel line for my LS1 swap Z. I will be sending you PM to ask for more specific questions. Thanks again.
Sorry for high jacking your post Slo_240SX.
Sorry for high jacking your post Slo_240SX.
12-13-2005, 02:45 PM
#7
Originally Posted by LS1GMCTruck
Alex, if you do indeed have 3/8" inch I.D.(inside diameter) fuel line already in the car, that came from the factory, and are routed the way you need them, then, yes...they are very usable. 3/8" is what the fuel supply line calls for on a stock or modified LS1 up to...say 450 h.p. or so. Steel AN female couplers can be bought at your local hydraulic hose supplier. You simply slide them over the end of the steel tubing & flare the end of the tubing with a flaring tool. You can then adapt any type of hose or fitting to that end now. 5/16" i.d. is the return line diameter. In AN sizing: 3/8"= -6AN...5/16"= -5AN hose & fittings. AN specifications were created by the Army & Navy for the militaries use, thus the term "AN". In fact, most of all the nuts, bolts, thread sizing, & most other hardware sizing was created by our government for use in WWll, as previous to this there was no "standard" size anything that exsisted. When something broke in the field, they did'nt know what part(s) to send to fix it, prior to this standarization. Hope this helps. Gar
Andy1
Trending Topics
12-17-2005, 10:40 PM
#8
Originally Posted by Andy1
Just make sure you use a 37 degree flaring tool, otherwise the flare will not be compatible with the AN fitting's.
Andy1
Andy1
12-19-2005, 09:25 AM
#9
AN Flare Angles... There are two AN flare angles that manufacturers, such as Eaton/AeroQuip, etc...make their fittings in...Society Of Automotive Engineers, S.A.E. 37 degree(commonly refered to as: "JIC" flare at the parts counter) & S.A.E. 45 degree(commonly refered to as just plain "SAE" flare at the parts counter). 37 degree is what most of the aluminum "Hi-Performance Series" of Eaton/Aeroquip fittings have. This goes for most all the other brands of performance aluminum fittings. So, when buying & mixing brands(Russell, Eaton/AeroQuip, Parker, Weatherhead, Cherry, etc.,) or fitting materials(steel, aluminum, stainless, etc.), make sure you note that your fitting-to-fitting connections are a match. If you hold up a 45 degree fitting next to a 37 degree fitting, you will see(obviously) that the 37 degree fitting has a "pointer" angle. Once this is set in your mind, you will always remember. As far as the flaring tool flare angle identification, you will have to compare the angle visually to an actual fitting, which is'nt too difficult really, as the two angles are quite different visually. Or, backtrack & ask your seller to tell you what angle you bought. The ideal tool will flare tubing to either angle, but I think you will find that the sharper 37 degree flare will be most commonly used in the aftermarket fittings. 
Gar
Gar Last edited by LS1GMCTruck; 12-19-2005 at 09:30 AM.
12-19-2005, 11:29 AM
#10
Teching In
Join Date: Dec 2005
Posts: 35
Likes: 0
Received 0 Likes
on
0 Posts
Hey I was hoping yall could clear somthing up for me somone told me that a LS1 swap fits so tight that the belt is almost scraping the radiator, and thus there is no room to work on it or modfy it, is that true? Does anyone have any pics of their complete LS1 swap so I can see for myself?
12-21-2005, 08:09 AM
#11
?????
Originally Posted by kachok25
Hey I was hoping yall could clear somthing up for me somone told me that a LS1 swap fits so tight that the belt is almost scraping the radiator, and thus there is no room to work on it or modfy it, is that true? Does anyone have any pics of their complete LS1 swap so I can see for myself?
Gar
12-22-2005, 09:08 PM
#12
TECH Enthusiast
Thread Starter
iTrader: (17)
Join Date: Sep 2005
Location: Detroit, MI - Camp Pendleton, CA
Posts: 619
Likes: 0
Received 0 Likes
on
0 Posts
Gar, too much info to process at one time! damn you are smart thanks for all the info its exactly what I needed. I have a regular brake line flaring tool... would you know thats a 37?
-Alex
-Alex
12-22-2005, 10:42 PM
#14
Teching In
Join Date: Dec 2005
Posts: 35
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by LS1GMCTruck
Kacchok25...Where the hell did this question come from??? Isn't this thread about fuel line sizing??? Gar
Gar
12-23-2005, 01:30 PM
#15
Yes, that is correct Org...
Originally Posted by org
3/8 ID or OD? Generally the sizing is OD and the actual ID will be that less the wall thickness AFAIK.
