I heard that the carbed fuel lines won't work very well with the SPFI fuel pump. Is it recommended that new lines are run from the fuel take to the engine compartment? If so where should the lines be run?? I tried to follow the existing fuel line but it goes up inside the body somewhere? Anyone that has done this can you give me some ideas before I start zip tying my fuel line right along the frame rails.

This is only in reference to the rubber fuel lines. The hard lines are fine. Simply replace all the rubber lines with EFI rated lines.

Word, Thanks. I just got some 5/16 fuel line from checker. I am sure that will work fine.

Whats the concensus on the rubber lines. Are the return and vent reinforced like the feed...do you have to replace all 3 systems worth of rubber lines or just the 1?

Whats the concensus on the rubber lines. Are the return and vent reinforced like the feed...do you have to replace all 3 systems worth of rubber lines or just the 1?

 

Other than the age factor, I don't think you would need to change the vent hose(s).

One definately wants to change the supply hoses over to the FI rated hose.

The return line hose(s) shouldn't really have any pressure on them, as the fuel is returning to tank and is just flowing thru the lines. Again, the age factor comes in on these as well.

 

As for the question on the steel lines and how they run thru the vehicle...

They pass thru the firewall, snake down the inside of the footwell area and run under the trim on the door sill on the lefthand side of the vehicle. The lines exit the interior under the back seat, or thru the backwall on BRATs

 

Left rear brake line is there also. Right rear brake line runs down the rightside of vehicle in the same manner.

 

I've ripped those lines out of an '86 BRAT, an '88 XT6, and an '86 Sedan that I've scrapped, all were ran the same way.

I would probably replace the return lines, too, just to be certain. It would be a shame to have the return line burst because it got pinched/plugged/restricted and got subjected to full pump pressure.

I've ripped those lines out of an '86 BRAT, an '88 XT6, and an '86 Sedan that I've scrapped, all were ran the same way.

But my question is: is the fuel lines the same size (EA82 EFI vs Carb) ? Or is the EFI on have bigger lines?

You need to replace the rubber return lines as well. The SPFI fuel pump for example puts out 50 psi of pressure, and a TON of fuel. The regulator on the side of the TB steps the pressure down to 21 psi, and you STILL have 21 psi of pressure in the return system.

 

Think of the fuel supply on the FI vehicles this way: It's a river of fuel flowing by at high speed, and high pressure. The TB regulator just "drinks" from the flowing river of fuel. The pressure in the supply and return are equal and thus both require the same high pressure hose. Go to a junk yard and puncture the return line of an FI subaru.... you'll find out real quick that there's plenty of pressure on both sides

 

The vent lines are not pressureized. They simply carry fuel vapor to the carbon collector. Regular non-FI hose is fine.

 

The hard lines are fine - the 20 year old steel lines in my Brat haven't shown any trouble carrying the FI pressure. And they are plenty large enough. You do have to step the sizes up from the tank to the pump. But really, this should be done at the surge tank fittings anyway. The tank in my Brat has no baffleing as it was carbed, and the FI does not like sucking air when the tank sloshes at stop lights and such. I have "ran out" of fuel before my fuel light even came on because the pump sucked air when the fuel sloshed around. If you sit for a minute and let the tank settle down it will restart, but it's annoying to not be able to use the last 2-3 gallons in the tank. A small surge tank will solve the problem. I found a web article where a guy made one from a houshold tap water filter canistor from home depot. I'm probably going to go that route as no one really sells anything appropriate for our application.

 

GD

One thing to note on the vent as well...

When I did this on my BRAT the vent canister was on the drivers side of the BRAT yet when you hook into the hard line at the back of the intake, it takes the vent to the pass side of the car. I just by-passed the hard line and took a hose straight from the firewall to the can, then I removed the hard line under the intake