More Fuel

[Steedjo]

Hey.

I was talking to a friend the other day about fuel pumps and how he knows a guy that can adjust the fuel pump and air mixture on cars to get more power out of them. This sounds like what a chip does.

Is this possible on newer cars like our navaras or not because the computer system controls how the air/fuel mix is calculated.

 

[Craig09]

from my understand this is what a CHEAP chip does,just adding more fuel isnt a good way of increasing power

 

[Steedjo]

from my understand this is what a CHEAP chip does,just adding more fuel isnt a good way of increasing power

Yea just adding fuel is not a good way, you need air to burn it. Thats where he reckon's this guy can adjust both air and fuel.

 

[tweak'e]

with diesels its generally just a case of upping the fuel. not many chips increase boost as well.
more than likely hes talking about the resistor trick on the pressure sensor. really crude way of doing it.

 

[Steedjo]

What is the resistor trick? Never heard of soon this and what's it's advantages and disadvantages?

 

[Old.Tony]

The resistor trick is a quick and dirty way of getting more fuel in.

Basically, the ECU sees your throttle position, engine load etc etc and determines that a certain amount of fuel rail pressure is required. Fair enough, that's a good way to do it. The injector will open and due to the exact pressure, an exact volume of fuel will pass through the injector.

What the resistor-chip does is reduce the voltage sent back from the fuel rail pressure sensor. This makes the ECU think the pressure isn't high enough, so it works the pump harder - so when the injector opens, more fuel goes in. It's really very simple.

The drawback with this system is that it's very crude (you can actually do worse - keep reading). Unlike specifically designed chips, there are no safeguards for when things get a little hot.

Don't be tempted to just throw a resistor in series with the fuel pressure sender return and hope for the best. This will change the return voltage across the entire throttle range - even idle.

While they are simple, they are effective - diesels naturally run lean because there's no metering of the air like you have in a petrol engine, so as long as the simple chips are operating within a reasonable range, they're going to provide a reasonable result.

 

[Steedjo]

Hey

Thanks heaps for the reply's and help. From my understanding of what he was going to do he was going to simply open up the fuel pump a touch more or something along those lines and also adjust the amount of air going into the engine, but that resistor thing sounds like its doing just that from the computer, rather than at the pump

 

[tweak'e]

i think you need to find out what type of injection pump hes referring to.
most of these there is nothing you can do in the pumps. old the old non-ecu pumps that are adjustable.

 

[Craig09]

i think the biggest thing is the fact that a decent chip may do a very simmilar thing to what this guy does (no idea what he does but either way hes changeing amounts of fuel and air from what you say) BUT they have protection measures incase something goes wrong or isnt safe for the engine instead of just makeing the changes differently and not being able to keep a eye on them.