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tpunx99GSX
12-18-2006, 02:14 PM
Ok This is just to give some backup to what i am saying to a buddy of mine.
He has a Turbo LS Vtec Integra. (yeah i know its a dsm site but hear me out)
He was talking to some douch bags on G2IC.com asking if his car would be ok with putting a 255lph fuel pump in without any fuel management (only temporary until he gets Hondata put on and tuned tomorrow). These guys were saying that he shouldnt because it will blow his motor because he doenst have fuel management. However he does have my dsm 450 injectors and a fuel regulator.
My stance on this is that being that he has a fuel regulator he should be fine being that the fuel regulator will regulate how much pressure is in that fuel rail for the injectors and the rest will be dumped back into the gas tank. To put it in simpler terms the Fuel Pump pretty much only makes it so that the injectors have enough fuel waiting for them when they open, and that no matter what, the injectors are only going to push in as much fuel as they can regardless of the fuel pump unless the fuel pump is too small or the fuel pressure is too low and starving the injectors. (i think i am saying this correct.)
Essentially they are telling my buddy that the fuel pump is going to flow more therefore more fuel is going to be dumped into the cylinders.
So can someone please shed some light on this. thanks
http://www.g2ic.com/forums/showthread.php?t=158483 heres the link.
TOm

CVD
12-18-2006, 03:06 PM
It looks like what they are saying is the fuel pump will not make it safe to make boost on a new turbo setup with no tuning. With a regulator just driving the car will not be a problem.
The original question was asked poorly and these guys answered what they thought the question was. They arent wrong, they just answered the wrong question.

Shane@DBPerformance
12-18-2006, 03:12 PM
It all depends on if the FPR can handle the extra fuel. If it is stock or a B&M add-on, then it probably won't be able to bypass enough fuel to keep the fuel pressure the same as before. Is a little extra fuel going to blow the motor? Extremely unlikely. During normal driving/cruising the stock O2 sensor will try to compensate for the extra fuel and under boost overrunning the FPR becomes less likely. To be safe, he could install it and baby the car until he gets it tuned, in cause he somehow installs it wrong and it gets less fuel.

tpunx99GSX
12-18-2006, 03:35 PM
Thats what i wanted to know. Thanks.
We are gonna install it tonight because hes getting it tuned tomorrow. I told him to keep off the boost no matter what until he gets some fuel management and tuning. So we shall see. He does however have a B&M FPR, hes gonna replace it with another one that can handle the Fuel pressure.

Shane@DBPerformance
12-18-2006, 03:44 PM
How is he controlling the 450cc injectors without Hondata on it yet?

tpunx99GSX
12-18-2006, 04:04 PM
What do you mean? They plug right in, the stock computer should handle it, Hell the car runs, The only problem with it running is major idle surge.

Shane@DBPerformance
12-18-2006, 04:36 PM
How can a stock computer programmed for 240cc fuel injectors handle 450cc fuel injectors that are almost twice as big? Changing fuel injectors is a much bigger deal than a fuel pump. Also, DSM 450cc injectors are low impedance, while Honda's run high impedance injectors stock. The ECU will get ruined, if a resistor box or inline resistors aren't used to compensate.

xveganxcowboyx
12-18-2006, 05:56 PM
If it runs he must have something. No resistors, plus no fuel control would mean no go.

tpunx99GSX, you must be missing part of the equasion here. Or do you mean he has them, but not installed yet?

I suppose he could drop the fuel pressure to single digits. :P


And just for the record, I had a friend who put a 255 in a barely modified civic DX and it ran with no problems. Several years and it still runs fine.