I don't mind fiddling with parts and pieces but for some reason I'm loath to 
start ripping out fuel line (hard lines, especially) in order to uprate them 
for FI.  I'd actually like to consider FI for my 128 but the fuel tank isn't 
set up for draw from the bottom.  Any ideas?  Do I need the larger lines or is 
that a nice to have?

MikeR (enjoying mirafiori.com since 1995)
'77 Fiat 124 Spider
'76 Fiat 128 4 door
Beaverton, Oregon

Also residing in the Magic Garage: son David's 86 X1/9

Previously owned:
'81 Fiat Spider 2000 Anniversary #236 
'78 Fiat 131 four door (sold in 1980)
'74 Fiat 128 four door (totalled in 1978)

Mike, for all practical reasons you do not need to change the hard lines. Just 
install the FI pump in the lowest possible location in the car, and make sure 
not to drive on an empty tank.

Val


Mike Richmond wrote:
: I don't mind fiddling with parts and pieces but for some reason I'm loath to 
: start ripping out fuel line (hard lines, especially) in order to uprate them 
: for FI.  I'd actually like to consider FI for my 128 but the fuel tank isn't 
: set up for draw from the bottom.  Any ideas?  Do I need the larger lines or 
is 
: that a nice to have?
: MikeR (enjoying mirafiori.com since 1995)
: '77 Fiat 124 Spider
: '76 Fiat 128 4 door
: Beaverton, Oregon
: Also residing in the Magic Garage: son David's 86 X1/9
: Previously owned:
: '81 Fiat Spider 2000 Anniversary #236 
: '78 Fiat 131 four door (sold in 1980)
: '74 Fiat 128 four door (totalled in 1978)

No idea about the 128, but on a 124, the stock hard lines are plenty so no need
to bother there. I'd 
definitely recommend the proper tank setup on a 124, but again, no idea about
how a 128 is setup.

Trent Wagner - Seattle, WA
'78 Lancia Beta Coupe
http://sickchilly.com

Webmaster - FIAT Enthusiasts Northwest
http://www.fiatnorthwest.org

Mike Richmond wrote:
: I don't mind fiddling with parts and pieces but for some reason I'm loath to 
: start ripping out fuel line (hard lines, especially) in order to uprate them 
: for FI.  I'd actually like to consider FI for my 128 but the fuel tank isn't 
: set up for draw from the bottom.  Any ideas?  Do I need the larger lines or 
is 
: that a nice to have?

I went through this same thing on my Yugo. Even though the engine is 
carburated, I had to use a fuel pump from a GM throttle body injected system 
in order to acheive at least 10# of fuel pressure. 

Electric fuel pumps are good at pushing but not sucking. However this pump is 
a diaphram style (not rotary valve like most FI pumps) so it might have worked 
just as well as the mechanical pump mounted in the engine compartment but I 
didn't try it. The instructions said to mount it below the tank anyway.

The problem on the Yugo is the inlet and outlet lines are in the sending unit 
and then feed into the cabin and run along the fake driveshaft tunnel.

The fuel pump must be mounted lower than the tank to provide head pressure.

I tried rerouting the inlet line below the tank then the discharge line coming 
off the pump back to the line going into the car but the clearance between the 
body and tank was so tight, it pinched the hose.

This is not the safest way to do it but here is what I did.

I pulled the tank (3rd time), flushed it out with water then washed it with 
Purple Magic. Flushed it again for about 15 minutes until I was satisfied all 
the vapors were gone.

Then drilled a hole in the center bottom of the tank. Then soldered a 90º 3/8" 
inlet fitting in the hole. I overlapped the fitting with a copper washer. Then 
used the vapor line that runs to the charcoal canister as the new supply line. 
I'm still using the 1/4" return line. Originally with the first pump I tried 
this caused too much of a restriction so I had problems reducing the fuel 
pressure.

I suppose the proper way is to take it to a welding shop where they can purge 
the tank with nitrogen and have them solder the fitting into the tank. 

James Seabolt  
Tennessee, United States
Homepage --->>> http://users.chartertn.net/jseabolt/

2003 Subaru Baja 
1980 FIAT 2000 "turbo" Spider
1968 Ford Fairlane 500 (Not a Ford Galaxie!!)
1987 Yugo GV 1500cc also turbocharged
1979 131 Brava (work in progress)

Mike -

As you know, both Val and Trent have BTDT on FI for carbed cars.  The only 
thing I'd add is a small resevoir, like 1 pint, just before the FI fuel pump to 
prevent fuel starvation on corners.  It won't be pressurized, so can be spliced 
in via the usual techniques.  Yeah, I know you don't like to push corners that 
hard, but it's still a good idea :-)

George Emery
http://members.aol.com/gemery -- "Twincams and Autox"

Frequently Asked Questions (FAQ) are answered here:
               general - http://www.mirafiori.com/faq
        model specific - http://www.mirafiori.com/model
             engine id - http://www.mirafiori.com/id
           smog system - http://www.mirafiori.com/smog
    parts substitution - http://www.mirafiori.com/sub
   wheels & suspension - http://www.mirafiori.com/dave
Thad Kirk's balljoints -http://www.mirafiori.com/~thad/balljoints/bj.html

For cars with no return line to the tank, perhaps it would be easier to fab up a
header tank in the engine bay that was fed by the carb fuel pump from the main
tank, and had both the feed and return lines from the high pressure circuit. 
This would solve both the fuel starvation issue and the return line issue. 

Another way to handle this, which involves more sophisticated electronic
knowlege, is to duplicate a modern "returnless" system.  This puts the pressure
pump back by the main tank, and varies the pump speed based on the fuel pressure
after the pump.  There's some work in the most recent MS codebases to handle
this, but I don't yet know if it's ready for prime time.  

George Emery (Oregon City) wrote:
: Mike -
: As you know, both Val and Trent have BTDT on FI for carbed cars.  The only 
: thing I'd add is a small resevoir, like 1 pint, just before the FI fuel pump
to 
: prevent fuel starvation on corners.  It won't be pressurized, so can be
spliced 
: in via the usual techniques.  Yeah, I know you don't like to push corners that 
: hard, but it's still a good idea :-)
: George Emery
: http://members.aol.com/gemery -- "Twincams and Autox"
: Frequently Asked Questions (FAQ) are answered here:
:                general - http://www.mirafiori.com/faq
:         model specific - http://www.mirafiori.com/model
:              engine id - http://www.mirafiori.com/id
:            smog system - http://www.mirafiori.com/smog
:     parts substitution - http://www.mirafiori.com/sub
:    wheels & suspension - http://www.mirafiori.com/dave
: Thad Kirk's balljoints -http://www.mirafiori.com/~thad/balljoints/bj.html

I used the stock carb tank when I did my Scorpion. The onlt real difference is 
that I used one of the vent lines as the return (because the stock return line 
was so small). As mentioned, mount the stock FI pump low and don't let the tank 
get too low. A pump from a Ford (F-150, Merkur, etc.) look exactly like the 
FIAT part (licensed by Bosch) but have a small hose fitting - unlike the FIAT 
one...

As George mentioned, a small surge tank is a good idea if you have room. I have 
one from an "A2" VW Golf (Jetta, etc.) that has the high pressure pump built 
right in. I will be using it when I get around to finishing the turbo, it will 
reduce the chance of fuel sloshing past the pickup (a no-no on a turbo car!). 
It has a supply line from the main tank (use a standard carb pump between the 
two) and a small return line to the tank. The high pressure pump pressurizes 
the fuel rail and another fitting is for the return from the fuel rail. Quite 
simple and compact (about 8" cube). It is designed to hang from below the trunk 
area, but I asume it could be mounted in the endine compartment.

John Allen
Tacoma, WA
(3) Lancia Scorpions
(1) FIAT powered DSR sport racer