I was just curious what advantage of having an upgraded fuel pump. Well it provide the car more fuel so you wont lean out? whats its purpose? I cant afford an ecu right now so and I have all my exhaust work done so was wondering what I Can do besides upgrading the ecu to prevent lean out or blowing up the motor. Well a fuel cut defenser trick the ecu in spraying more fuel so I dont get fuel cut? well that be a good fix for the time being for my mods regarding the exhaust work for the time being?

 

well ricki again thanks for you reply, well my mods are knn drop in filter in the stock air box, downpipe, midpipe, and free flowing catback. Rebuilt turbos aswell with new actuators.

 

Hi Suprakiller

No fuel pump upgrading is needed with your mods.
But sometimes a stock fuel pump breaks.
If it doesn't work at all, we can notice easily.
But some of them, the fuel pressure is getting lower and lower.
Then, motor will be seriously damaged.
We are required to swap fuel pump every 50000km.
And spark plugs every 5000km by Mr. Amemiya.

 

you might want to port your wastegate, if you are getting boost creep.

 

A fuel pump need only be adequate for the application. If you have an adequate pump and replace it with one that flows twice as much, you won't get any more fuel into the engine. The regulator controls the pressure, and the fuel pump just needs to supply enough fuel to maintain the pressure.

If the fuel pump is inadequate, the fuel pressure will drop under high load (boost + inj duty cycle) and that will reduce the amount of fuel delivered. The ECU has no clue what the fuel pressure is, so it just holds the injectors open for X amount of time. If the pressure drops, less fuel will be delivered in that time. So, all you need is a pump that can flow enough to maintain the regulator pressure when the boost and injector duty cycles are at their peak.

A fuel cut defenser can only reduce the amount of fuel delivered, because it fools the ECU into thinking you are running less boost.

You can increase your fuel pressure to get more fuel without changing the computer, but that puts extra stress on the fuel pump, as it is more difficult to pump fuel at higher pressures.

The first step you should take is to get the car on a dyno (or do some hard runs on the street) with a wideband O2 sensor. The stock one is only accurate at 14.7 A/F ratio, so don't use it to judge your mixture outside of that range. If you are running lean, then you should look into some options. A fuel pump and an adjustable rising-rate fuel pressure regulator will give you more fuel if you need it. A merely "adjustable FPR" will raise fuel pressure at all manifold pressures, which will make your car rich off boost. A "rising rate" regulator only increases fuel pressure under boost, which is what you want to avoid screwing up your off-boost mixture.

-Max

 

No ECU? Someone's in need of one BAD...especially with that full exhaust!

 

How's Amemeiya-san doing?

 

Amemiya-san wa? Genki? jspecracer7no kuruma wa okinawa ni iru. Ja-ne!

 

if i am understanding this correctly...in order to increase fuel supply and lower injectory duty cycles you need both a fuel pump and an adjustable rising rate regualtor????
do i really need bigger secondaries if i run full exhaust, intake, powerfc, and M2 IC? I really do not want to upgrade the injectors.

matt

 

don't need injectors yet unless you want and can up the boost past about 12psi

check the thread about max hp with stock injectors

 

i posted there too

 

i would like to run 14 psi safely...not all the time but when i race

 

you need injectors then

 

yo dude ,ya souldz bizuy a bizoost controller so yaz dizont runz overz the 10 pizoundz of bizoost nigggggggggga

 

You obviously don't know much about FD's. If the wastegate is already getting overrun, then a boost controller isn't going to do much.

 

Actually, I think he(Kill All RX-7's) does know enough...to kill all RX-7's, apparently.

MODS,
Do we have to put up with this guy's(Kill All RX-7's) inane moniker and his even more idiotic post? Couldn't one of you just zap him into oblivion?

 

what's wrong ya little bitches don't like my name well then f uck off go cry in a corner,why don't u try to zap me into oblivion or even try,i think you have watch too much star wars talking about zapping someone into oblivion give me a break,**** OFF

 

You realize what you wrote?

 

wouldn't u like to see him try,i think it is mr.spock, so i'm kinda scarred cause they do have phazers right?maybe he'll zap me to another world full of big titted **** actresses

 

You really might want to out your main cat back in until you get an ECU. FCD or a FP will not help you (save you). Do you have a boost gauge? At least it would be a good start to know how high the boost is going.

As you likely know, typically intake, CB and DP are as far as you want to go with out an ECU.

Recently, I read post stating that more mods can be supported by the stock ECU as long as the boost does not go over 10 psi. I personally do not know if this is true. You can make a manual boost controller from hardware store parts. Never tried this.

IMHO Your driving on very thin ice.

 

Wade Lanham has a wide band O2 sensor and has gathered some info on this subject .
He has good fuel info on his site.