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MG MGF Technical - new injectors ?

Hi all,
do anybody know somethings about the EXTRA POWER INJECTORS (160 BHP),they say (on the box of the injectors) that you will have more power with them, is it true or don't we win a lot compare than the standard ones.
thanks a lot
see you there
pascandrea
pascandrea

Injectors designed for higher power engines will give less power on lower powered units.
Will Munns

Let me put that another way. The thing which limits an engines power is how much _AIR_ it can get in and expell, then the ECU adds fuel to taste.
Injectors spray pattern is designed to be best when fully open, using injectors designed for high powered engines will cause the injector to be switched on for a much shorter time, and therefore provide a worse dispersal pattern.

This is of course if you remap your ECU, if you dont then you just slap in more fuel than you can burn and you end up with less power due to being over rich, and bore was causing untold dammage to you moving parts.
Will Munns

Hi again
thank you very much for your help but i forgot to tell you that i change my engine for a 52mm TB and a K+N filter, so maybe now the power injector maybe useful ?
regards
pascandrea
pascandrea

Hi pascandrea,

I have to completely concur with what Will has said - using larger injectors on a standard engine will have almost no effect upon performance - and frequently quite the opposite, as I and many others have found (using fuel pressure regulators - but the principle is the same).

You can read more here: http://www.mgf.ultimatemg.com/group2/fuel_rail/index.htm

In closed loop running, only enough fuel to give a Lambda value that equates to lean running (and therefore fuel efficiency) will be pumped into the engine. On open-loop running (when you've floored the throttle), you get fueling that is dictated by the fuel map in the ECU. If you've fitted larger injectors, then too much fuel can enter the engine, which will result in a rich mixture. A rich mixture takes longer to burn and burns cooler - partly because you need more oxygen to burn the fuel, and partly because the fuel is displacing oxygen laden air...

Larger fuel injectors/ higher pressure fuel regulators only make sense in the context of cylinder head modifications where you've got dramatically higher air flows- in these cases you'll get more power if you pump more fuel in.

Sorry, but a larger throttle body and a higher flow airfilter won't make that much difference. :o(

Save your money for other mods - cams for example ;o)
Rob Bell

Hi
thanks guys your are really helpful, as always,
you know so much about this car that you must be the conceptors,
see you there
pascandrea
pascandrea

This thread was discussed between 27/04/2005 and 28/04/2005

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