I have a RC10GT and my fuel lines are pretty short, I see all these other RC10GT's on here and they all have about 2 feet of fuel line on them, is there a reason for that or is everyone just not cutting it shorter? Is there a performance reason or is it personal preference?

i'm not sure of an actualy technical reason, but on my jato when i ran short fuel lines as opposed to the stock routing (about 10 inches longer) i noticed that whenever it would flip over and land on its body it would die. when i went back to running the fuel lines long it could stay on its body for a much longer period of time. other than that i don't see a reason.

I think thats the only real reason. I remember some people who raced would put like 2ft of tubing on their trucks. they said they could store more fuel in there and have better races due to that extra fuel. I think its just a bunch of hog wash but if you really believe that stuff...[:-]

Google it, I am sure you will find an answer somewhere, I know there is a very vailid reason for it, just I can't think of it right now.

I agree with the first two responses... Do a search here, not on google.

Its definitely for longer upside down running time. Another alternative I've heard people doing is putting a large fuel filter on the line without the filter stone in it in so it acts as a reserve tank and gives more upside down run time. Who really wants to run over to their car/truck when they flip it anyways? [8D]

Thats correct, it usually has to do with getting more runtime ( with a racetruck you adjust the capacity to the CC, so fuel line length is used for this ) and for less chance of an upside down flameout.

Its about expansion and pressure. Very little help but none the less help. The presure that goes into your fuel tank from your exhaust pipe is limited to what it can produce so that if there is more volume room (longer fuel lines) the pressure remains more stable. Kind of like blowing air into a little box or a big box. Which holds more air [&:]

^^Right. The pressure is sent to the tank in waves from the exhaust. The added fuel line acts to stabilize the pressure.

Added upside-down time, too.

^^ interesting...

If thats how it works then a fuel filter could be used as an expansion chamber as opposed to a longer line on your exhaust to the same effect right??

If so then I finally have the right answer to a thread I started asking about exhaust line fuel filters.

I do it for longer running times. (it take longer to pass though the whole line)

You say it has longer run times but the motor is going to use the same mount of fuel regardless right? And the tank is only going to hold so much, now I see how it would run longer on its lid, cause it is already has the fuel in the line and it doesnt have to pull from the tank for a few seconds or so. I would think the shorter the line, the less pressure it would take to pressurize the fuel to the carb. The less pressure means less back pressure and higher rpms. If the motor doesnt have that extra load on it wouldnt it free up some power on the top end? I mean the back pressure may give some torque but im sure the numbers are so small, it wouldn't be worth mentioning.

yes but once you prime your engine you could top off the tank and have a few more CCs...

Then next time you fill up, you have a full tank + whatever is still in the line. With a fuel filter and long lines you could maybe get 2-3 more CCs...

yeah the fuel filter on the exhaust line is fairly commonly seen in oz on the 8th offroad guys cars.

There is no load on the engine from pressure output that would even be measurable. A big fuel filter would net you about 1/20th of an ounce of fuel and it wouldn't help as far as the sustained pressure in the tank because it doesn't expand. A fuel tank and fuel lines have the ability to expand under pressure. The more room to expand (longer fuel lines) the better the pressure stability is for feeding the carb. This is such a miniscuel ammount of help to the system its more of just the possibility of anything helping rather than it being a must do thing. I do it myself but its more of something to talk about than anything else

I don't think the amount of fuel in the filter(or 2, I have heard of people doing), and the lines, equates to much added driving time. It makes a significant difference in idle time on it's lid.

Adding a bit more fuel line could help stabilize the idle, if it is choppy, and surges. This is due to evening out the pressure. I wonder if you could go too far, and run so much fuel line that the increase in pressure from climbing RPMs would lag, and create a lean situation under WOT acceleration....? Then conversely it would flood out when you let off the throttle from WOT, I suppose....
I would guess that there would be different effects from having a short pressure line and long fuel line, vs., long pressure line and short fuel line.

I have heard of people running a filter on the pressure line, too. I assume it is for trapping any soot or debris that could be in the exhaust system.
Personally, I don't run a pressure line, so that isn't an issue for me.