fuel line question

[jmerc]

I asked this question in the general technical forum and got it almost answered thanks to the guys there . It was suggested there that I ask here so Ill rephrase and ask you racers. SOME BACKGROUND INFO :I have an 85 Monte SS ,350, 30 over shot peened and race prepped, scat 4340 crank, arps studs, high vol oil pump w/ high vol shaft and rod, speed pro pistons/ flat top 9:1 comp, ported and polished 882 heads, roller rockers, new springs locks and retainers, keith black push rods, double roller timing chain, comp cams nitrous/sc cam, .507 int lift .525 exh lift .284 dur int ans .305 dur exh, 113 lob sep, solid lifters, B & M 144 blower totaly rebuilt, Demon 750 cfm, long tube headers, holly performer mech fuel pump, TH350 fully built, shift kit, 3500 stall, 9" converter, eaton posi 4:11 gears. I normally only use the car to drive Grandma to church on Sunday but weve been running a little late lately so I figuered I needed to upgrade, LOL only kidding OK heres the question. I removed the stock gas tank in prep for redoing the rear suspension, (back half w/ 4 link or hotchkins style adjustabls, not sure yet , but thats another question) Im in the process of installing a foam filled racing fuel cell but see that the original tank had 3 fuel lines going to it. 1, the main fuel line and from what I learnd the othe 2 being a return line and a vent line that went to a carbon canister. My current fuel setup does not have a return so Im almost positive from what people have told me that a return is not nessessary , any thoughts on that? Also what do I do about venting of the new tank?

 

[jmerc]

So no thoughts on how to vent this tank?

 

[jusbo]

I'm not a racer but lets see if we can think this through.
So you are going to be putting in a new tank? Is it a fuel cell or something of the stock form? Are you still going to use the mechanical fuel pump? If so you don't need a return thats for sure. If it is a fuel cell then it will have a vent built into the sender that when tipped a bobber inside closes it off so no fuel pours out if (God forbid) a rollover should occur.
Let us know more of what your new situation is and maybe we here at the forums can help out a little bit further.

 

[rccktmn2]

You can only run one line for the for the carb, there is allot of debate but from what I've found as long as your not running allot of fuel pressure you can get away with one line. As far as the other line coming out of the fuel cell you can use that for a vent. No matter what you need a vent on the cell or you wont get anything out of it.

 

[gbodydude]

must fuel cells have a vent on top.looks like a a/n fitting.

 

[bjohn07]

what kinda fuel system u running? mech or electric pump, mech u wont need a return, electric depends on flow and pressure. u can always run a dead head with electric but u will get vapor lock on a long drive. and a return on a electric will help ur pump to last longer. and since ur putting a fuel cell in u might as well run some new lines and take out the fact ones. the rci fuel cells i use always have 2 outlets, i cap one off, a vent and return, i usually run a dead head so i cap off the return. and the vent has a rollover valve. i usually put a bulkhead through the trunk floor with a small breater. like a spectre attached on the bottom. and i run a 3/8 fuel line from the rollover to the bulkhead. and give it a few loops. helps to keep any gas from dropping out through the bulkhead in the floor. the only way u can run a return is by using a bypass style regulator. and the fact has 3 lines, one for fuel supply, the fuel injection cars had returns, and the vent was for the evap. hope this info helps good luck

 

[mickey-d]

If you run a mechanical pump, all you need is a feed line, and a vent, which should already be there. If you run an electric pump, you should use a pressure regulator and a pres. gauge. You don't need a return unless you are running a lot of pressure all the time. ..................mickey-d :lol:

 

[Blammotor]

3/8 line is ok but if you plan on any track time I would run a 1/2 in line for supply

 

[Phoenyx]

I don't know anything about the gas tank. But about your rear suspension. Are you tubbing you car? If not I see no reason to back half it. I can't give you any actual numbers. But I'm sure someone here can tell you. Just upgrade the factory arms, no need to back half it, unless you have 1000+HP and are running 8s lol. Check around in the suspension section. Lots of info there. Maybe you'll save a few thousand dollars this way.

 

[ALaRock]

I am currently running a feul cell and i have one line that goes from the tank to the electric feul pump from the pump to the filter and from there to a regulator and my carb. I have the vent an fitting on the top of my tank which i believe all have and i used that with some extra feul line and i have a hole i ran it through in the trunk and all is good. The tank is properly vented outside the car and it is mainly incase of a rollover or so fumes don't build up in the car.

About the suspension with your set up i would suggest getting a set of lift bars from jegs they are 200 dollars i believe and maybe getting a set of upper adjustable control arms and no need for the back half. Unless if your after it for the looks of some big meats under the rear than with your set up it is not currently needed like stated above. You could fine tune your set up with the parts listed above. Hope this is helpful. 😀