Well, not exactly. Moving oil for the sake of moving oil has three consequences. First, you are heating the oil. Its just like running a monster electric fuel pump when you don't need it. As oil serves a secondary function to lubrication, namely cooling, artificially heating the oil is putting heat into it and reducing it effectiveness as a cooling medium. Oil does not reject heat very well, so changing its temperature up or down takes a while. This additional heating is probably not an issue, unless you're having problems keeping the engine cool, in which case its directly contributing to overheating.
Second, and this is the real cause for concern, in a wet sump engine as oil drains back into the pan through various drains it falls on the crank and rods and gets whipped into what looks like taffy. What you are seeing is the oil being aerated. The problem with this is that air doesn't make an acceptable cushion in place of oil, as its compressible. In any wet sump system this is going to happen, but the degree to which it happens is still important. A HV pump is moving a lot more oil, and the oil is going up and coming back down more often, which means its hitting the rotating assembly more often, and getting aerated more often.
Third, there is more load placed on the distributor gear and oil pump driveshaft. Using an ARP shaft likely staves off failures. The gear, it depends. I've seen 5.0s shear the roll pin that holds the gear to the shaft (I've also seen this in 300 I6 engines, so I don't want anyone to think I'm drawing a false corollary. I've seen advice from 5.0 experts who say to increase the size of that pin +1 size to prevent it, so maybe it can happen no matter what, but it does make you think. The real rub here is that you are just wasting power spinning that pump. I'd love to see a dyno test to see exactly how much. I've heard outrageous claims in the 30HP range, but nothing to back that up. I guarantee it costs something though.
In the end all I can say fro sure is that I've never had an engine failure due to oiling on any SBC, BBC, or SBF I've built and I've always used a standard volume and pressure pump that I've at most personally blueprinted. In my younger years I just tossed the pump in and also never had any failures. Now I blueprint them, but I blueprint everything; its just how I do. What red351 said about shimming the bypass spring is also something I've done from time to time, but only on engines I expected to rev beyond 6,000RPM.
I can say that I do read a LOT. I've yet to find the book where a professional engine builder recommends an HV pump in any of the applications mentioned. A lot of these guys spent months testing various ideas, running engines with windows cut in them, clear oil pans, etc. to see what actually happens in a running engine. I've also yet to talk to a machine shop that has recommended a HV pump. In the end, I've built quite a few engines over the years, but I still defer to the guys who've built tens of thousands of them. Without that reading and those conversations I likely would ascribe to the bigger is better, more insurance philosophy too. That comes down to the fact that I don't have a dyno room, and can't afford that kind of testing to investigate theories, BUT the guys who make a living at engine building can, do, and have. Their knowledge and experience is out there. All I've been doing for 20+ years is heading it.
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MS wrote:
No efi, no trans tunnel mods, no...You know, thinking back this all started with the chickie on the cell phone...it's all HER fault!
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