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

Twin intank?

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Old Apr 12, 2009 | 12:50 PM
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Default Twin intank?

I just finished up installing twin intank 255's and I have a question. The setup is in a 01 Silverado with a return style fuel system. My question is should the fuel pressure increase from the base pressure when the second pump is on? At idle I normally have a base pressure of 54 and if I jump the hobbs switch my fuel pressure jumps to 75 at idle. I thought the regulator on the fuel rail would keep the fuel pressure at 54 until it sees boost? Is this normal? Can the stock return line not flow enough to bleed off the extra fuel pressure?
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Old Apr 12, 2009 | 08:08 PM
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The regulator & return line are not up to the task of returning the flow for 2 pumps. It will cause a large pressure increase as you are seeing at idle. This is why you use a hobbs switch to bring the second pump on only after the engine is using a considerable amount of fuel.
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Old Apr 12, 2009 | 08:39 PM
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Originally Posted by Lonnies Performance
The regulator & return line are not up to the task of returning the flow for 2 pumps. It will cause a large pressure increase as you are seeing at idle. This is why you use a hobbs switch to bring the second pump on only after the engine is using a considerable amount of fuel.
Thanks for the reply. I thought that might be the case so I drove it around for little bit with the hobbs switch set on 2psi and its working good.
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Old Apr 12, 2009 | 09:06 PM
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How's that truck running now?
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Old Apr 12, 2009 | 09:19 PM
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It's still slow. I'm going to put the new turbo on this week and see if I can't surpass the 600hp mark.
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Old Apr 12, 2009 | 09:23 PM
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Uh oh, you going bigger? Your truck was/is not slow, it's pretty nasty for a 5500 lbs. beast!
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Old Apr 12, 2009 | 09:35 PM
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Originally Posted by 1fast bird
Uh oh, you going bigger? Your truck was/is not slow, it's pretty nasty for a 5500 lbs. beast!
Going bigger. I picked up a TC76 BB since the MP70 was maxed out. Hopefully it will hold together for Superstallions.
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Old Apr 12, 2009 | 09:41 PM
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I'm sure you will find the next weak link in it with 600 hp. What's next, twins? This truly is a disease! lol.....Let me know when you need to step up to 96lbs. injectors, cause I have a brand new set I won't be using.
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Old Apr 12, 2009 | 09:50 PM
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I should be fine with the 60's. With the new fuel pump setup and meth that should hold me over for quite a while. Now I need a forged bottom end and an 80e so I can shoot for 750-800.
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