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WinRice WinRice is offline
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Join Date: Jun 2005
Location: Colorado
Posts: 700
Originally Posted by Dr J View Post
Added a 1 mm shim to increase FD pressure by 0.6 bar. That worked. Pressure was 5.6 bar but flow was about the same. According to the calculator from the link above, I should have expected about 9 ml more fuel per injector.
Not necessarily, you may be hitting the flow limits of your pump.

Look at the charts below, I couldn't find a chart for your 053, but the 979 is close:

Once you hit around 5.5 bar the flow rate drops drastically, and the current demand goes way up, indicating the pump is maxed out in efficiency.

Now lets look at the 044

You should be able to run that pump at 6 - 6.5 bar fine, giving a flow rate around 3.3 L/min (1650cc / 30 sec), which is close to the 1500cc / 30 sec given by the factory 930 system.

Also notice the big flow rate drop after 7.5 bar, if you need more than 7.5 bar with a good flow rate, a series pump system like the 930 is the way to go.

More pump info:

Bosch and Lucas Fuel pumps
1986 911 Turbo
3.3L, K27HFS, Tial 46mm, TurboKraft Intercooler, 964 Cams, Monty Muffler, MS3Pro Evo, M&W Ignition, Zietronix WBO2 Data Logger, Wevo shifter, coupler and motor mounts.
Old 01-24-2010, 09:54 AM
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