Fueling & Injection Fuel Pumps | Injectors | Rails | Regulators | Tanks

Y Block and Dual Walbro usage

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Old Mar 22, 2010 | 04:37 PM
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Default Y Block and Dual Walbro usage

Can anyone tell me the best place to get a Y Block to hook up my Walbros and also how important is it to have the second pump on a hobbs switch. Is there any real problem with letting them both run? This is on a Turbo application. Thanks
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Old Mar 22, 2010 | 07:27 PM
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you can make your own Y-pipe or just look in summit, earls, etc.

some people will say to run the Hobbs as you don't need them running all the time and doing so will only heat the fuel, etc. Others will say it is fine to run both and having the switch is only one more thing to go bad
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Old Mar 23, 2010 | 10:09 AM
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You can find the fittings at home depot, or any local hardware store.
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Old Mar 23, 2010 | 10:33 AM
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Im leaning toward letting them both run... I dont really see what it can hurt...
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Old Mar 23, 2010 | 10:57 AM
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looking to do the same thing with my e85 setup, just leave them both on full time.
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Old Mar 23, 2010 | 10:58 AM
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Running both creates heat and over heating the fuel causes pump failure.
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Old Mar 23, 2010 | 11:00 AM
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If you don't have a need for the larger volume it will just heat up the fuel. The y-block from THD is actually an air fitting and will be over with the compressor stuff.

Edit: Beat me to it.
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Old Mar 23, 2010 | 03:12 PM
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Does anyone know where to buy just a hobbs switch?
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Old Mar 23, 2010 | 03:20 PM
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NAPA....Part number for a normally open 4psi hobbs switch is:

701-1575
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Old Mar 25, 2010 | 06:57 PM
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Advice for wiring it with a hobbs? Any special relays really needed or anything?
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Old Mar 25, 2010 | 09:33 PM
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Use the hobbs switch to trigger a relay.

For a good, cheap AN Y, redhorse has the best option.

http://www.redhorseperformance.com/parts4/index.htm

For the rest of the fittings, 30* hose ends will run off of the Y parallel for a clean install.
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Old Mar 26, 2010 | 05:01 AM
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Wiring it up isn't that hard. Wire your fuel pump to a 30amp relay, and run a wire from the ground prong of the relay, to the Hobbs switch. The ground the Hobbs to the frame. Voilà!
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Old Mar 26, 2010 | 01:43 PM
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Originally Posted by blk00ss
Wiring it up isn't that hard. Wire your fuel pump to a 30amp relay, and run a wire from the ground prong of the relay, to the Hobbs switch. The ground the Hobbs to the frame. Voilà!
That is backwards, but it will work.

The more correct way is to wire the relay terminals thus:
30 - 12v supply, battery or alternator
85 - ground
86 - Hobbs switch
87 - fuel pump

Wire the Hobbs switch to key-on 12v.
When you power on the vehicle, the Hobbs switch has power on one side. When you go into boost, the Hobbs switch activates, and sends 12v to the relay. The relay then activates, and the pump receives 12v and runs.
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Old Mar 26, 2010 | 06:02 PM
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Thanks guys... good stuff.
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Old Mar 26, 2010 | 07:55 PM
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Nice info guys. It helped me!
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Old Mar 27, 2010 | 10:25 AM
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Letting both run is fine. 03/04 Cobra's, the Ford GT super car, etc all run dual in tank pumps ( much larger than the walbro 255's to boot ) full time from the factory and there aren't any issues.
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Old Mar 27, 2010 | 02:23 PM
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Make sure ur return line can carry the fuel back fast enough I have a 8an line with two 340 a 6an return base fp is set at 60 with two pumps on at idle it jumps to 71 psi cause the return can't flow enough
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Old Mar 27, 2010 | 09:23 PM
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Originally Posted by Bad Notch
Letting both run is fine. 03/04 Cobra's, the Ford GT super car, etc all run dual in tank pumps ( much larger than the walbro 255's to boot ) full time from the factory and there aren't any issues.

You are mistaken, as those pumps are speed controlled & do not run at full output constantly.

As for dual intank Walbros, I always recommend not to run them both continuously.
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