Jump to content
1 tuff z

ls1 fuel line feed & return sizes

Recommended Posts

i searched and can't seem to locate what size lines [feed & return] everyone is using for the ls1 swap. i found info on how to plumb the return, incorporate a pressure regulator & pump.


i'm putting a 76 280 fi tank into my 240 and the shop that 'boiled it out' said that he can also braze "an fittings" on the tank, just need to know the size. want to get them attached prior to painting.


also, any recommendations on; fuel pumps, fuel filter [an fitting & in-line], pressure regulator & fuel rails greatly appreciated!




Share this post

Link to post
Share on other sites

I am using the stock 78 tank for now. Walbro 255L fuel pump, 1/2" feed line, 3/8" return. Both are aluminum lines from Earls. The Walbro pump has M10 X 1 threads on both the intake and outlet. The engine has Speed Inc fuel rails and a billet fuel pressure regulator. I purchased a 2001 LS1 tank last month to install during the winter (if I'm not still trying to get the car on the road damnit!) I was going to just replace the stock lines, but I think I will do a high tunnel install as the regulator and feed are both on the rear of the fuel rail. That will keep it simple.


Of course I say this will all work, but the installation of the fuel stuff was supose to happen this week and I have had to postpone it because the car's electrical has a short in it somewhere that I'm having problems finding. Soon there will be only one wire left!

Share this post

Link to post
Share on other sites

Found info on it over at ls1tech when I had the same question.

Apparently for non drag only cars under abour 450 hp a 3/8 feed and 5/16 return should be one.

They actually said a 5/16 feed was probably ok.

I'm setting mine up the same as yours, using the corvette filter/regulator.

The input to the filter is 5/16 and output and return are 3/8, so I'm just using pipe to an fittings on each to -6 line.


Share this post

Link to post
Share on other sites

Hello all

I'm using 5/16 inlet and outlet.

Edelbrock f.p. regulator pumped up to 60p.s.i.

John's cars pump. Looks like Walbro 255 pump???

Stock 280z tank

NO-PROBLEMS!!!!!! Well uhh except when I first got the car done. My line from the regulator to the rail collapsed on the inside. I had 60 p.s.i. at idle and it dropped to like 35 on a hard rev. All good now!


Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...