Pretty in Pink, dunno why
Join Date: Feb 2009
Location: Redondo Beach
Oil is being diverted away from the crank/cylinder wall/piston, which is the primary objective.
The diverted oil is going to the transmission and cams. To do that it must go through banjo bolts that we have enlarged, which is done by drilling a 1/8" cross hole through then bolts that feed the pipe (the 'middle banjo') and the cams. The transmission banjo is not cross drilled; its single hole is opened to 1/8". If it were opened by cross drilling then there would essentially be no restriction in the oil line save for that introduced by laminar flow. Laminar flow is a bit of a red herring, though, because it exists anywhere that the oil has to change direction or squeeze through a restriction. Thus it is pretty much a constant so there is not a lot of sense in talking about it. If it only existed in the transmission and the cams were lubed by flooding from an open pipe then it might make sense to talk about it.
The cams have enough oil to make them happy in the stock configuration. Sending more oil to them is not going to make them happier. That said, though, we don't want to do anything which would drop the pressure to them. Since both the transmission and the cams are getting more oil than in the stock configuration, it makes sense to play it safe and go with the type of banjo that Paul has chosen.
One can see this intuitively by looking at the lubrication flow diagram and seeing that the transmission has 50% more leakage points than the cams do. This, coupled with the knowledge that the transmission shafts are considerably larger than the camshafts, would tell you that the transmission leakage is going to be higher than the cams and you'd want a restriction on the transmission side of things.
Hope that makes sense.
Tom [email protected]
“If I wasn't hard, I wouldn't be alive. If I couldn't ever be gentle, I wouldn't deserve to be alive.”
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