Thread: Leaske WUR
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JBL930 JBL930 is offline
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Join Date: May 2006
Location: UK
Posts: 1,172
Not standard on a 930, it's something that Brian Leask developed to aid in tuning the adjustable WUR. See it as a simple on/off tap. In stock form a pipe is fed directly to the WUR from the manifold, so that as soon as boost builds a diaphragm in the WUR moves and lowers control pressure, lower control pressure means more fuel through the injectors. Problem being 2 fold, a more modern turbo like the K27 will produce boost quicker, it will also produce more power. To tackle the extra power you need more fuel, so you adjust your WUR to give you more fuel, BUT because you are also building boost sooner you get this extra fuel too soon.
You cut the pipe going to your WUR from the manifold and fit the RPM switch, you then put a certain chip in the switch to open the tap at a certain RPM point, say 4200rpm. You then hook up the RPM switch to your tach (or elsewhere, someone else will help). Then the boost to the WUR only gets through above that RPM level, which means you only get the extra fuel when you want it. Does that make sense?
87 930, 993 turbo engine, RS Tuning 520PS/515lbf-ft, Arrow Rods, ARP hardware, Solid lifters, G50-50, RS Flywheel, 890nm Sachs clutch, RSR coil overs all round, 993 C4 calipers front, 930 fronts on the rear, Ruf Speedlines.....
Old 540 BMW, XB12S Modified, for being a total hooligan
Old 03-10-2009, 11:13 AM
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