So i'm going to put a edelbrock on my car, and i know it runs at about 5.5 or 6 psi. So i got a carter fuel pump that pumps 7 and a holley 4.5-9 psi regulator. any way, the pump recomends using 3/8" line. The stock line on my '79 is 5/16" i believe. Do i have to up the line size? and if i do, what do i do about the line size from the tank as it a hard line 5/16" into the tank.?

 

It runs alot cooler like that and extends the life of the pump if you run 3/8". I'll be running that for my feed and return on my FI setup

 

how about the tank pickup tube? can it stay 5/16"?

 

there would be no point changing all the other lines to bigger lines if those are going to remain stock. A system will only flow as much as its most restrictive point. Some people have taken them out, drilled in bigger holes and JB welded them in there.

 

Hrm. How hard would this be to do? And wouldn't if i up the lines after the pump be well enough? I mean its less back pressure on the pump still. No?

 

It will still be the same pressure regardless of if you just do the front, because onces the fluids fill up all the lines, they will only flow just as much as its biggest openning. Personally I'm actually going with an Intank pump for my FI stuff which is why I was selling my carb stuff.

But for the 79 tanks I'm not sure exactly how they are, but I know that the 81-83 cars are a little harder, than say the 84-85. Because the 84-85 car you can actually remove that part. If you search this forum you will be able to pull up from pictures.

 

the sa are like the 81-83. no rad shop here will increase the line size for me unless i know how it runs on the inside. Can anyone help me here?

 

What do you mean unless they know how the insides are? Like I said you can do yourself if you wante too, but there should be some speed shop that will be able to do such a thing.

 

I'm not 100% sure. its what they told me. I thinks it so when they pull them out they have to know how they do pull out.

 

I'd leave it at the stock 5/16. My REPU has a Carter that was installed 10 years ago. The line size is 5/16. No problems. Actually the only problem it ever had was due to the stock rubber hoses having been stretched over the 3/8 nipples on the Carter. I had to repare them when they started leaking. I had to splice in a couple short 3/8 pieces of fuel line and some 5/16 metal tubes. The 3/8 line squeezes down to 5/16 a lot easier than 5/16 line stretches out to 3/8.

 

I've got an extra '83 pick-up tube that mounts to the tank. It runs down inside and has a curve in the line inside the tank. I'm going to swap my '83 tank out to an '84 SE, so I could possibly drill out the pick-up tube in one of my '83 lids and weld in a 3/8" hard line for you. I've got all the parts I need to do it, but I won't be home until tomorrow and could possibly get to it this weekend. I've been welding for years and have all the right equipment to perform this modification with no problem at home. If you'd be interested, PM me and we'll discuss it. I won't try to rape you with the price either. Thanks...

-Adam Collins