Author Topic: Tank vent size.  (Read 5188 times)

Offline BK

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Tank vent size.
« on: April 04, 2016, 06:21:28 PM »
 Checking for a friend. Wondering what size the tank vent should be for 1200HP.

dreracecar

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Re: Tank vent size.
« Reply #1 on: April 05, 2016, 08:42:43 AM »
If the tank is finnished, remove tank and take it outside and cap all the inlets and outlets except for vent. Fill to the top with water and close fill cap. Remove main line cap and watch water flow, it should be a constant streem, if it surges (like an old man peeing) then the vent is too small.

 I ran a 5gal tank with a 7/8" dia feed tube to a 110 pump SBC blown in 7.0pro and used a 1/2" dia vent line front to back and a "T" in the middle and then forward, venting was never an issue

Offline Rusty Kramer

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Re: Tank vent size.
« Reply #2 on: April 05, 2016, 10:42:52 AM »
We are feeding a little more motor but 1-1/8" ID feed line.  3/4" ID vent.  Pee test like a young guy and works good on the car. same type vent as DREracecar has front and rear vent with a T in the center

Offline masracingtd1167

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Re: Tank vent size.
« Reply #3 on: April 05, 2016, 12:20:22 PM »
If the tank is finnished, remove tank and take it outside and cap all the inlets and outlets except for vent. Fill to the top with water and close fill cap. Remove main line cap and watch water flow, it should be a constant streem, if it surges (like an old man peeing) then the vent is too small.

 I ran a 5gal tank with a 7/8" dia feed tube to a 110 pump SBC blown in 7.0pro and used a 1/2" dia vent line front to back and a "T" in the middle and then forward, venting was never an issue
     Like an old man peeing ! Funny stuff ! Just remember after you turn 60 never pass a bathroom and never trust a fart !

Offline hotrod316

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Re: Tank vent size.
« Reply #4 on: April 06, 2016, 05:37:50 AM »
there is one more 8)

Offline Spud Miller

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Re: Tank vent size.
« Reply #5 on: April 10, 2016, 09:09:18 AM »

Fuel Injection Enterprises, LLC
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dreracecar

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Re: Tank vent size.
« Reply #6 on: April 10, 2016, 06:44:48 PM »
Two things I might add to your "perfect tank"
One is that the aluminum to use is 5052H32, this is a marine grade and holds up to corrosion better than others
Two is that there's problems with anodizing alu. As it's hard to repair cracks or add on to without complete chem strip on both the inner and outer surfaces. If these areas are not clean raw alu, then the weld is contaminated and a poor weld..I ran a raw tank for 20 years without issues, just drain it after the weekend