I was working on my car the other day, "Installing a TB Mod" and realized how friggin small the fuel lines are in these T2 cars. I found a couple of set up's on how to do the fuel rails with 6an line and a regulator. But what are you people doing for the fuel supply and return lines? I was thinking that perhaps a lot of these Disasters with blown engines could be the pisshole sized line these cars come with from the factory.

 

The fuel lines are HUGE. The fuel lines and rails are good for 500+ HP.

 

i have read the rails are rated for 500hp but i have a hard time beleving the lines are HUGE as you said.
Ive built a couple fast cars ie 10 second 1/4 mile in my day and I think a upgrade would help a few differant fuel related issues. Maybe im just used to seeing larger fuel lines than those om the Mazda.

 

The stock diameter lines certainly would be a restriction compared to larger diameter lines, though depending on the rest of the fuel system this may or may not be a factor.

For instance, if you run something like the Aeromotice A1000 series external pumps the instructions specifically adress the issue of less flow from pressure drop of small diameter lines. I believe that this is from the large component size of the pump mechanism- causes drop in flow at very high pressures.

The smaller Bosch 044 pump that is well suited for high pressure applications would most likely not suffer a substantial drop in flow from higher pressures at the pump caused by pressure drop in lines on the way to the regulator.

So, depends on the rest of the fuel system....

 

I agree that it would be application spesific. I was having a problem with the 500hp rateing.
I always figured in a performence application consideration should be made for both Volume as well as Pressure.

 

I use both the factory supply and returns as dual supplies and have added a 1/2" return to the tank..I run two fuel pumps on a sumped tank.... I wouldn't trust the stock fuel system to 500, and definetly not the stock fuel filter..Max

 

Well Like said above there are lots of people running 400-500 hp on stock diameter return and feed lines.

I have upgraded my engine bay lines though.
Stock fuel ijection hose for inlet but I use a Aeromotive 1000FPR and 6an return. Also using a Walbro pump.

 

I would be inclined to throw a fuel pressure gauge on my system and keep an eye on it, if I were the type to be making more power than my mostly stock NA made. If the pressure starts dropping at high injector duty cycle, upgrade the lines/pump. If it's constant, then don't worry.

Alternately, get a gallon container, put the source fuel line into it, crank up the fuel pump with the test jumper, and see just how "little" the lines can flow.

-=Russ=-