Thread: MFI in a 930
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jcge jcge is offline
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Join Date: Sep 2007
Posts: 500

Rack movement vs fuel delivery - this is from test plan data for the normally aspirated R3, R3Y & R3Z pumps with 6mm plunger.

Assuming you need to get to 65cc/500 strokes (this figure was posted by Bernie Buschen on his 935 pbase gallery) = 130cc/1000 strokes, you'd probable need to look at a 7mm piston (1.36 times the area of the 6mm piston) to not "overextend" the rack.

You can tell plunger size externally from the ID plate on the pump

PED6KL60... = 6.0mm
PED6KL70... = 7.0mm
PED6KL75... = 7.5mm

You can see from Max's photo that it is very difficult to read the ID plate as its located on the inboard side of the pump next to the inlet manifold.

I believe that Gus Pfister at Pacific Fuel Injection supported many turbo pumps over the years.

I think lightened flyweights and different control springs also help extend the speed range of the space cam, but just speculation on my part.

Further, I've heard that these egines were "fuel cooled" (very rich)

Last edited by jcge; 01-12-2010 at 06:47 PM..
Old 01-12-2010, 06:45 PM
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