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OP: The mods suggested by the tuner look fine, all except for the fuel pump. For 400 RWHP, a 255LPH pump will be sufficient. (Calculations show that a 190 is actually adequate, but the 255 gives a little head room.) A larger pump does nothing but recirculate the unused fuel, raising its temperature. You can see my mods in the link in my signature if you're interested.

EDIT: And would a full AN fuel system be nice? Yes. Is it needed for your goals? No.
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A 255 pump will cause a restriction because it's trying to flow 255lph through a tiny feed line. The restriction will be caused on the return side and not allow the fuel pressure regulator to function properly. This will show up on a gauge as a higher than normal fuel pressure with a unsteady needle.

Also you can always tell a mustang that has a 255 in with stock lines. It whines something crazy because it's trying to flow at 255 but the tiny lines will not allow it.

Don't overlook a proper fuel system design.
 

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Discussion Starter #23
If anybody here is familiar with the al9 computer system I have a question. Alot of people are running thicker gauge wire due to voltage drop to thier fuel pump. They are by passing the fuel pump relay, and wiring there own relay. When I look at the fuel pump relay schematic, I see the relay sending voltage to control module, and the inertia fuel shutoff switch. Can we just bypass that stuff? Or does the controls module need to see votage from the relay?
 

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The dark green / yellow wire is confirmation to the computer fuel pump is on. This should be for error codes only. Use the light blue / org wire as the ground trigger for the new relay (85 or 86 on standard 12v relay). Its fine to bypass inertia switch and wire power to 30(from fused 12v batt source) thru 87 directly out to fuel pump. It would be just as easy to reconnect that dark green / yellow wire to that same 87 out so the computer gets the correct 12v signal and doesn't throw codes.
 

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I would not bypass the inertia switch. You wreck it, its on fire, and now the fuel pump is still running spraying gas on the fire.

Could the existing power wire to the pump be used to trigger the new relay? That way you don't bypass the existing features.
 

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Discussion Starter #26
Yes I suppose I could T off of the red 12v wire and clip the 12v feed at the pump. Everything else would work as designed.
 

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Discussion Starter #27
Is. Anybody seeing any real gains using this "power pipe." I was given this for free. The alternative is running a 180 off the inlet of the supercharger, with maf and k&n air filter. I have scott rod panels and a custom shaved & tucked engine bay. I'm not Interested in cutting holes in it for plastic pipes. But, if I could gain 20 horsepower I'd be interested.
 

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Mine is in my sig. Stock bottom end. TW 170's and custom cam from FTI. RPMII. 75mm TB and 90mm maf with 60lb. injectors and a 255. A trim making about 7-8 lbs. I would guess it to be 375-400 @ the tire w/ T5.
 
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