gmorrell
Never been a noob...
At the risk of incurring moderator wrath, I'm going to re-open this subject because the original thread was closed as I was responding with an answer to gmail's question. It might not be the answer he's looking for, but it's the only answer I have, and as far as I'm concerned, it's the right answer, so here goes:
Regarding gmail's comment about the pressure relief setting.
No, he's right, the Ford/Yamaha SHO engine book says, and I quote:
OK, let's get something out of the way fairly early here.
Information was sometimes hard to get, and it was often costly. Since buying my SHO in 1989, I've expended a good deal of energy, time and money learning lots of things, so you'll forgive me if occasionally I'm reluctant to part with my valuable information just because getting it for free is what you're used to.
Now, about shimming the oil pump, specifically the 3.0L pump. Been there, done that, got the tee shirt. I have flat-ass defeated the pressure relief in the 3.0L pump and installed an expensive Peterson Fluid Systems adjustable remote oil pressure relief valve in my remote oil filter/cooling plumbing. It made almost no difference in hot, high RPM oil pressures.
The reason for this (I suspect...) is that the 3.0L pump is just flat out of capacity to flow more oil volume. I don't care what you do to the oil pressure relief valve, you can weld it solid shut, and you're not going to see much more oil pressure because the pump simply can't move any more oil volume.
The solution, I believe, is the 3.2L pump, which has a geroter that is 20% wider than the 3.0L pump. This pump will move a larger volume of oil over it's entire RPM operating range, so raising the pressure relief setting may actually accomplish what you're wanting to do. Good luck getting one, they're unobtanium. I'm certain that Ford/Yamaha didn't make this oil pump change lightly, because there really appeared to be no reason for it - the 3.2L engine has the same number and size bearings, the same clearances, etc. The only reason I can fathom for this larger capacity pump is that some engineer was paying attention and discovered that this engine, irrespective of its displacement, needed more pumped oil volume.
Regarding gmail's comment about the pressure relief setting.
No, he's right, the Ford/Yamaha SHO engine book says, and I quote:
I quoted this text directly out of the copy I have saved on my archive drive. I also have a published/bound copy of this document that was given to me by Ford's service training manager many years ago.
OK, let's get something out of the way fairly early here.
Now, I've earned the right to be an ass occasionally, but the other 99% of the time, I'm damn helpful and forthcoming with information, and you can browse around this forum to see ample evidence of that. I grew up and got my engineering degrees in a time when information wasn't always so easy to come by: There wasn't any internet, or Google, or even any forums like this one. You wanted to learn something, you bought books, or you went to the library and borrowed them, or you sent requests (by snail mail) to borrow materials from other libraries, and you waited, sometimes weeks. Or you sought out people with more knowledge than yourself and asked questions - nicely, and maybe you bought them a beer... or three. (I also walked to school, every day in the snow, uphill both ways, and ate cold gravel for lunch.)
Information was sometimes hard to get, and it was often costly. Since buying my SHO in 1989, I've expended a good deal of energy, time and money learning lots of things, so you'll forgive me if occasionally I'm reluctant to part with my valuable information just because getting it for free is what you're used to.
Now, about shimming the oil pump, specifically the 3.0L pump. Been there, done that, got the tee shirt. I have flat-ass defeated the pressure relief in the 3.0L pump and installed an expensive Peterson Fluid Systems adjustable remote oil pressure relief valve in my remote oil filter/cooling plumbing. It made almost no difference in hot, high RPM oil pressures.
The reason for this (I suspect...) is that the 3.0L pump is just flat out of capacity to flow more oil volume. I don't care what you do to the oil pressure relief valve, you can weld it solid shut, and you're not going to see much more oil pressure because the pump simply can't move any more oil volume.
The solution, I believe, is the 3.2L pump, which has a geroter that is 20% wider than the 3.0L pump. This pump will move a larger volume of oil over it's entire RPM operating range, so raising the pressure relief setting may actually accomplish what you're wanting to do. Good luck getting one, they're unobtanium. I'm certain that Ford/Yamaha didn't make this oil pump change lightly, because there really appeared to be no reason for it - the 3.2L engine has the same number and size bearings, the same clearances, etc. The only reason I can fathom for this larger capacity pump is that some engineer was paying attention and discovered that this engine, irrespective of its displacement, needed more pumped oil volume.
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