MembersPage/MarcellGal/PowerAndTraction/FuelDelivery (2007-06-13 07:43:03)

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s2central or sjmautotechnik talks about differences between AAN and 3B. (TODO: find the link).

That means sqrt(4/3.5) = 1.07, so 3B injectors flow 7 percent less, therefore require req_fuel of 7% more. (also roughly 7% more cranking pulsewidth).

Cranking pulsewidths (cwl/cwh, in msec)


Injector size

Brave men do like this: in audi 5cyl 20vt thmb rule: cc/per injector = max power in hp. 440cc = 440 HP

I think it's brave. But with tuned boostcontrol it can be tried. If going up slowly, one will know when running out of injectors flowrate.

I think there is an error on http://www.rceng.com/technical.htm they swapped the BSFC for turbo and supercharged. Turbo is better (lower). Below I calculate with BSFC(gasoline)=0.55l / (HP * l), consistent with some other sources.

examples

Safe injector sizing

If purchasing new injectors, it is best to have it sized high enough to be enough for sure, for the times to come.

The injector sizing should be rather 420 HP with K26/27 turbo (even if we'll more likely get only 370 HP).


Fuel Pump

Kalske's hints in this case is to use 044 pump in PnP install inside fuel tank

First two are the most important ones, they are used fitting the pump in place of the original one. Banjo, seals and nut are used for fuel line connection.

It is weird that banjo is used inside the tank, for the fuel pressure line. Doesn't the 90 degree break obstruct the flow ?

http://www.avtoshop.net/audi.php?mdl=141&bildid=2670005F&grp=9&check=16

Fuel pressure sensor

Currently not installed. Would be nice though. Not sure what is a good place to install it on 3B engine. Obviously, before FPR. But I just don't like the idea of messing around fuel tubes.


Fuel Pressure Regulator MAP reference

LogAnalysis of the boost-run revieled a problem though:

With the 30V transient diode flyback you just don't expect that much difference. The analysis revieled that the FPR reference was connected to athmosphere. Stupid mistake, should be connected to MAP.

Connecting to MAP makes the