fuel pump

i am slightly confused. i have heard many times of people getting bigger fuel pumps to add power, but i dont get it. the fuel is controlled by the computer right? so no matter how big your pump is, the output will be the same. i am also under the impression that our ECUs cannot be "reflashed" or "reprogrammed" or whatever you wanna call it. can someone please explain?

a larger fuel pump will flow more fuel at the same voltage as the stock pump.. the larger the pump the more fuel it will flow. correct our ecu's can not be reprogramed or reflashed. this is what an apexi safc is for. u get larger injectors and a larger fuel pump and it will alow you to run higher boost pressures.(of corse with all the supporting mods that you need) the safc will be what u control the larger injectors with. hope this clears some things up.

Very important, any time you swap out an electrical component that uses more power you need to make sure the wires you have running to it can support the extra flow of current.

both pieces of advice are correct and just to elaborate adding a bigger fuel pump wont add power all it can do is flow more consistantly so you dont run to lean when adding boost. And yes always make sure the wires can haddle the current!! Power adding to cars is all about air to fuel ratio and when you get an safc it alows to you match the amount of axtra boost (air) to the amout of fuel needed. If you dont plan on upgrading your turbos any time soon you dont have too much to worry about because the 9b turbos can only produce power up to about 14-15 psi as well as that is about all the stock fuel system can keep up with. Behond 14-15 psi not only will you be running very lean and can ultimately cause engine melting but the turbos will be running too hard therefore pushing in very hot air that the stock intercoolers cannot cool down efficeintly enough the produce power. Hope that helps a little. :)

what if i just put in an FPR on the stock system? that would get more fuel to the engine, right?

what if i just put in an FPR on the stock system? that would get more fuel to the engine, right?

Up to a point. Increasing the pressure would result in an increase in volume delivered but the total volume is dependent upon the volume the fuel pump is capable of delivering.

is the stock pump capable of delivering more than it delivers with the stock pressure? or would a aftermarket FPR be useless without a bigger pump? also regarding the wiring/voltage issue: you can upgrade a bigger fuel pump w/o redoing wiring, correct? im not talking about a HUGE pump. how big could i go without causing electrical problems?

This link has loads of info and will probably answer most of your questions.

http://www.stealth316.com/2-fuelpumpguide.htm

you wont have any problems with wiring on different fuel pumps unless it says it is a higher voltage pump. And for the fpr well you can run more pressure but that pressure will only be good until it gets to the injectors. The injectors can only push a certain spec without using a fuel controller. Adding a fpr to stock injectors and stock electronic fuel system might give you more consistant pressure to the injectors but thats about it.

This link has loads of info and will probably answer most of your questions.

http://www.stealth316.com/2-fuelpumpguide.htm

THANKS ALOT! this really answered SO MANY of my questions. i still do have one though :biggrin:. on that page it says that the walbro 255lph pump should be used with 450cc injectors, but after some searching, i am having a hard time finding smaller than 550cc for our cars. anyone know i site with 450s?

450's are stock DSM turbo injectors.

THANKS ALOT! this really answered SO MANY of my questions. i still do have one though :biggrin:. on that page it says that the walbro 255lph pump should be used with 450cc injectors, but after some searching, i am having a hard time finding smaller than 550cc for our cars. anyone know i site with 450s?

If you're still running the stock 9b's, you don't need 450's.

yeah but i wanna upgrade soon. been looking at the 3sx eliminators, but they say they need 550s at least so. . .nevermind. but if i upgrade the turbos, the only other things that need upgrade are the fuel pump, injectors, regulator, intercooler, and some kind of AFC correct? i know some of that isnt exactly a neccessity but, i want POWER. :biggrin:

450's are stock DSM turbo injectors.

and i thought the stock was 360cc? or are 3s's not DSM?

Stock TT is 360, DSM's come stock with 450's. 3s's are not DSM's


I dont understand how you got confused.

i guess its cuz magazines tell me that 3s's are DSM. what IS considered DSM then?

dsm's were made in normal, illinois 3s's were made in japan.

most mags dont no what the hell there talking aout whe it comes to 3ks, there all more toward to standard civic, 240s, evos and stis....but when it come to 3ks there few and far between and full of misleading information...bottom line, our cars rock
SAMSUNG-SGH-I617/1.0 Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 7.6) UP.Link/6.3.1.17.06.3.1.17.0