Go Back  Offshoreonly.com > Technical > General Q & A
Fuel system setup >

Fuel system setup

Notices

Fuel system setup

Old 01-23-2012, 08:38 AM
  #1  
Registered
Thread Starter
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default Fuel system setup

How much HP would this setup support.

1/2" tank pickup, 5/8" fuel line to Fram racing fuel filter, #10 line from filter to 1/2 NPT inlet on Holley 130 GPH self regulated six valve mechanical pump. 1/2 NPT pump outlet to #10AN line going up to four port fuel block. Then #6 line to each carb bowl. Dual 850 Holleys on top of a 420 B&M blower.

Trying to keep a simple fuel system but with large lines and no 90* adapter fittings.
MILD THUNDER is offline  
Old 01-23-2012, 06:21 PM
  #2  
Registered
 
Join Date: Jan 2007
Location: Murrayville Georgia
Posts: 1,812
Likes: 0
Received 889 Likes on 318 Posts
Default

not an expert but I would say far more than the 420 blower will make.
compedgemarine is offline  
Old 01-23-2012, 09:16 PM
  #3  
Registered
 
Bustinan1022's Avatar
 
Join Date: Jun 2011
Location: Conroe, TX
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Default

Your GPH will only flow as much as your smallest line. I think the 1/2 is good for roughly 130 GPH free flow and here s a quote explaining how to calculate what you'll get. You can play with the numbers in the formula below.


The average advertised weight of a gallon of premium fuel is 6.34 lb/gallon.
Brake Specific Fuel Consumption or B.S.F.C.
Brake Specific Fuel Consumption or B.S.F.C. is the amount of fuel required to produce 1 HP for 1 hour. This means that an engine with a B.S.F.C of .5 will burn 1/2 or .5 lbs of fuel to produce 1 HP for one hour. Determining exact B.S.F.C for a specific engine is complicated and requires an engine dyno.
Based on industry standards the B.S.F.C for:
Normal Aspirated Engines is .45 - .55
Supercharged Engines is .55 - .60
Turbocharged Engines is .6 - .65


need to calculate fuel required:
Target Hp * B.S.F.C. = Fuel required in lbs/hr
600 *.56 = 330 lbs/hr
Most fuel pumps flow rate is advertised in gallons per hour:
Lbs/hr / fuel weight per gallon = gal/hr
330 / 6.34 = 52 gal/hr
but remember pump losses, and a fuel pressure regulator and a return line fuel feed system designs flow requirements ?

Last edited by Bustinan1022; 01-23-2012 at 09:42 PM.
Bustinan1022 is offline  
Old 01-23-2012, 09:52 PM
  #4  
Registered
iTrader: (3)
 
Join Date: Oct 2007
Location: yorkville,il
Posts: 8,427
Received 87 Likes on 49 Posts
Default

thats almost the same setup as my cat has,and they are 950hp at 6200 rpm,no need to worry,wlll work great for your power.
mike tkach is offline  
Old 01-23-2012, 09:57 PM
  #5  
Registered
Thread Starter
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default

Thanks guys. Trying to keep it simple. I have a few extra of these six valve 1/2" in/out mechanical pumps for spares. I bought two brand new ones last spring.
MILD THUNDER is offline  
Old 01-24-2012, 12:52 AM
  #6  
Registered
 
Join Date: Jan 2004
Location: Tennessee
Posts: 4,480
Likes: 0
Received 40 Likes on 16 Posts
Default

Originally Posted by MILD THUNDER
How much HP would this setup support.

.
As much as your setup will make
That will do fine for any amount that 420 can muster. Good luck.
Eddie
Young Performance is offline  
Old 01-24-2012, 09:17 AM
  #7  
Registered
Thread Starter
iTrader: (3)
 
Join Date: Jul 2004
Location: chicago
Posts: 11,332
Received 71 Likes on 39 Posts
Default

Originally Posted by Young Performance
As much as your setup will make
That will do fine for any amount that 420 can muster. Good luck.
Eddie
How do you guys feel about electric fuel psi gauges? For some reason, i just dont trust them. I was thinking of adding in a fuel psi switch, that will trigger the alarm and LED light should the fuel psi fall below say 5psi??
MILD THUNDER is offline  
Old 01-24-2012, 09:44 AM
  #8  
Registered
iTrader: (3)
 
Join Date: Aug 2007
Location: Sandown, NH - Sebago Lake Region, ME
Posts: 2,960
Likes: 0
Received 6 Likes on 6 Posts
Default

Originally Posted by MILD THUNDER
How do you guys feel about electric fuel psi gauges? For some reason, i just dont trust them. I was thinking of adding in a fuel psi switch, that will trigger the alarm and LED light should the fuel psi fall below say 5psi??
Fully agree!

I have an LED on the dash that blinks if psi drops below 4psi and I have mechanical gauges mounted on the engine. You can see them in the big plate that holds my MSD,coil, etc.

502ss is offline  
Old 01-25-2012, 09:40 AM
  #9  
Registered
 
Join Date: Oct 2010
Location: Cheboygan, MI
Posts: 1,621
Received 398 Likes on 229 Posts
Default

I have a similar setup on my boat, my concern is sucking through the filter. Is it better to pull through the filter or push through it? I have been thinking about using a mesh prefilter to the pump and then push through my final filter. I am using a WIX 3522 filter which has a built in water separator and has twice the filter area of the standard Fram. Interested in any opinions, I'm running about 700hp through the Merc seawater pump, and I know I'm at the limit of this setup.
ThisIsLivin is offline  
Old 01-25-2012, 03:31 PM
  #10  
Registered
 
Join Date: Jan 2004
Location: Tennessee
Posts: 4,480
Likes: 0
Received 40 Likes on 16 Posts
Default

Originally Posted by MILD THUNDER
How do you guys feel about electric fuel psi gauges? For some reason, i just dont trust them. I was thinking of adding in a fuel psi switch, that will trigger the alarm and LED light should the fuel psi fall below say 5psi??
The electric gauges are notoriously inaccurate. However, they usually always hold the same inaccuracy. Even though they aren't usually correct, they should read the same all the time. Your best bet is the set the pressure with a mechanical gauge first.
Eddie
Young Performance is offline  

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.