MINI2 - MINI Forum - View Single Post - Pre-facelift R53 Boost Pressure

Lucky Dave · Apr 28th, 2008, 09:22 AM

Quote: Originally Posted by Silent1 (original)

Fuel economy has gone down slightly, it's definately not gone up.

Standard fuel pressure is 3.5 bar
It came set to 3.0 bar which is the recommended setting for 440cc injectors, without the spacer it's maximum is 3.2 bar, to get it any higher you need to fit a spacer, but this then means you can raise it up to 4.5 bar, so without a gauge there's no way for me to check the fuel pressure, so my only option is to refit a standard pressure regulator and see if i get any changes.

ETA, as for the closed loop, this is the problem i think, with the pressure drop the injectors aren't as efficient at atomising the fuel, therefore it's putting more in and running it rich.

The pressure drop will put less fuel in.

Its simple bigger hole injector needs less pressure to deliver the same fuel.

The other option is to increase the pressure on stock injectors, but your fuel pump will be maxed so its cheaper and easier to inlarge the injector size AND reduce the pressure, if you dont reduce the pressure buy running a stock reg then you will be even richer.

Apr 28th, 2008, 09:22 AM	#13
Lucky Dave Thinking Minis My Classifieds Join Date: Jun 2005 Local Time: 02:42 AM Posts: 803 Offline	Quote: Originally Posted by Silent1 (original) Fuel economy has gone down slightly, it's definately not gone up. Standard fuel pressure is 3.5 bar It came set to 3.0 bar which is the recommended setting for 440cc injectors, without the spacer it's maximum is 3.2 bar, to get it any higher you need to fit a spacer, but this then means you can raise it up to 4.5 bar, so without a gauge there's no way for me to check the fuel pressure, so my only option is to refit a standard pressure regulator and see if i get any changes. ETA, as for the closed loop, this is the problem i think, with the pressure drop the injectors aren't as efficient at atomising the fuel, therefore it's putting more in and running it rich. The pressure drop will put less fuel in. Its simple bigger hole injector needs less pressure to deliver the same fuel. The other option is to increase the pressure on stock injectors, but your fuel pump will be maxed so its cheaper and easier to inlarge the injector size AND reduce the pressure, if you dont reduce the pressure buy running a stock reg then you will be even richer. For All Your Mini's Needs 01905 620011