You must have never rode in my 240 Baja. You had to fight not to flip over the seat when I hit that thing. The whole boat would leap out of the water. There was no getting on plane :-)

I'll be more specific than just saying automobiles - street/strip and more specifically drag cars.

Example: A 600hp motor accelerates lot more hard in a suspensioned / tired car than the same motor in a boat can ever think of.

That's what I was referring too.

Just to be clear.

Not to take away from boats.

Sounds like I should have ! Would have loved that !

Edit in: Double post.

118 - .101V Viton Stock Holley. For use
in low output motors, 450 HP and below,
using 4-barrel carburetor. Useful in
preventing high RPM enrichment on
speedway motors with restrictor plates.
Flow capacity 125#/hour @ 7 p.s.i. and
.25" float drop.

118 - .110V Viton Stock Holley. Used in
most applications, up to 650 HP with
4-barrel and to 400 HP with 2-barrel.
Flow capacity 175#/hour @ 7 p.s.i., .25"
float drop.

118 - .120V Viton Stock Holley. Used in
most applications, up to 775 HP with
4-barrel and to 500 HP with 2-barrel.
Flow capacity 215#/hour @ 7 p.s.i., .25"
float drop.



118 - .130RV Largest Viton needle and
seat available. Recommended for high
output 2-barrel motors and single 4-barrel
motors producing over 750 HP. Will flow
275#/ hour @ 7 p.s.i. and .25" float drop.
Will not hold idle pressure above 8 p.s.i.

With that information, lets say you have two .130 needle and seats to provide fuel to. .130x2=.260. Thats a little over 1/4'' or .250 diameter for the 2 needle and seats. Now, the smallest diameter in a #6 line, is .30. A #8 line, is .390. A #10, .48. Not talking about the hose inner diameter, but the actual size of the thru hole at the flare.

Now, Lets say your engine NEEDS .130 seats, to provide enough fuel to the engine. You can see, where a #6 line, with the same 7lbs of pressure, will work, as it should be large enough, barely. A #8, even better. However, that is on the PRESSURE side of things. The inlet side of things, doesnt move as much as fuel since obviously its not under pressure. Therefore, you can see where a #6 would not suffice in that situation.

So basically, when it comes to fuel lines, better off erroring to the large size is always a good idea.

Yup, line length, bends, turns, abrupt flow direction changes, etc all effects things.

Let's keep the good info going.

Don't forget to line up the windows of your N&S with the inlet of the bowl when adjusting your floats.

Some N&S companies are thoughtful enough to line the windows up with the flats on the adjusting nuts but not all doe this.

Just a tech tip while on the subject.

Just putting this out there. Not all -an fittings are created equal some are high flow some not. All are overpriced.

MT you can't figure it that way....Its pie R squared... ie: take a .130 needle .. it would be .065x .065x 3.1415 =.01327 times two needle & seat per carb = .02654; now a 1/4" hose or tube would be .125x.125x3.1415 =.04908. Its almost double

Makes sense. I guess you need to look at the orifice as a circle, rather than just the diameter.

So, the question is, if we know lets say a .130 needle and seat can flow roughly 275lbs per hour, or 45 gallons per hour, times 2 for a single carb.....What size fuel line does one need to be able to move more fuel or at least keep up and move 90 gallons per hour, with the carb at 7psi of pressure? Then we need to calculate losses for restrictive fittings, bends, length of line, and so on. Thats for the pressure side.

Whats the calculation for the inlet side of the pump, when dealing with suction?

Correct . Can't go by diameter. We want to go by area.

Thanks, easy to forget.