Pretty sure its the stock location from memory .. No 2000rpm its already there. Penrite racing 20w/50 E85 Ran 10w /40 on 98 . .
I'll be the first to say I don't know my oiling but that does seem high. Are you running a TT oil pump? Something something TT oil pump without one of the release valves due to the NA tree?
Apparently over 90 psi a bypass valve opens which means oil isn't been filtered . Don't think it matters which tree you have . someone else can chime in with facts. . .
That would be a bad thing then? Going off your numbers 4500 RPM + your oil is unfiltered? Or does this occur across the board anyway?
Oil is only unfiltered if there is pressure drop from one side of the filter to the other, nothing to do with absolute pressure or pressure relative to ambient, just pressure drop from the outgoing line to the incoming line. If the inline twin coolers add enough resistance or if the cooled oil doesn't flow through the filter properly then that may open the bypass valves but if it's flowing fine there should be no problem. I would say the most reasonable guess as to why the pressures are so high is that the oil flowing through the engine is pretty thoroughly cooled so it's extra thick.
Nah, Blackies stated oil temps are held quite high via thermostats so thats not a factor. Nor is the oil weight. Is why his setup is so superior. Its been thought out and well planned. The engine oil pressure is set by the primary pressure regulating valve. It works in precisely the same way as a FPR. Oil filters, by design, dont filter full flow of oil anyway at high flowrates and unless some very funky and specific "Full Flow" (aka" Toilet Roll") oil filters are employed. The ordinary single pass pleated paper filter medium can collapse if their pressure differential exceeds *blah* psi blocking the filter entirely and possibly introducing filter medium into the oil system. Im guessing its 50psi or thereabouts. So, dont worry too much about your oil being only being partially filtered. It happens every day for extended periods of time in just about every engine made when you rev it up above (circa) 50psi!!!!! On one of my bikes, the only oil that is ever filtered at all is bypassed oil from the primary pressure regulator. Its never been changed in 35 years!!!!!!
Thanks E. So in this thread it's been stated that NA oil pumps and TT oil pumps differ in that the NA has an internal bypass valve, while the TT set up includes an additional one on the filter tree that goes to the oil cooler. If that's the case, what's the best approach for a TT oil pump equipped engine with an oil cooler fed via a thermostated sandwich plate - NA tree, or TT tree with original bypass valve plumbed straight down into the sump with a restrictor (like the Z1 kit)? No issue running the NA tree with a TT pump, despite losing a relief valve? Sorry if I've got any of my facts wrong and please correct me if I have.
Your pretty close M8. The TT tree has a bypass valve to direct oil to the stock cooler and back to the sump the NA tree doesnt have the cooler fittings so the very same bypass oil just dumps back to the sump. IIRC the TT oil pump is a higher volume job. I think that if you wished to add a sandwich plate, a downstream thermostat and bigger coolers, youd be better off to use the NA tree. E
The NA doesn't have the bypass period, so it doesn't return any bypass oil back to the sump. It's a completely separate feature of the TT tree. Personally I think the best option from the information provided in this thread is the TT tree with the bypass fed straight back to the sump as per the Z1 kit. The boys at Z1 are pretty switched on with their zeds.
Right, cool. Differing opinions on the NA having a bypass though? If the NA tree lacks a relief valve (compared to the TT anyway) I guess it's a queston of whether the higher (?) Oil pressures are preferable. Fielding all inputs, got no idea here.
I don't know if such a high oil pressure would cause any problems? But it's not what the engine would normally see with the TT oil tree. Be interesting to get peak oil pressure figures from someone with a stock NA running the oil pressure sensor off a similar location to a TT.
That's right, but Rob (Black Beast) reported his pressures from the stock location on a TT which is the oil feed to the passenger turbo, same location I use. Just need to plumb a sensor into the block on the NA where this oil line would come out on a TT for a comparable figure.
The NA tree still has the little spring loaded ball bearing oil filter bypass / pressure drop feature, but it doesn't have the pressure valve that bleeds off pressure to the oil cooler and back to the sump. So there is nothing on the NA that bleeds pressure back to the sump that I'm aware of other than the pump itself.
Okay. I haven't heard much beyond hearsay about VGs and oiling issues. If it ain't broke, don't fix it; stick with the TT tree?
The only motivation for the NA tree is removing clutter and eliminating a potential leak, still need to plug/weld up the return port in the sump though. With regards to the different pumps I have a feeling strength is the more important difference between the two, Nissan made some pretty delicate oil pumps in the early 90s so the chunkier TT unit is probably good insurance for higher revving builds. Pressures seem close enough that I wouldn't be fussed about swapping the pump relief springs or anything.
I think people are getting mixed up with terms and parts here On a 300zx na or tt. The oil pressure relief valve is built into the pump. That will cap oil pressure at 60 or 70 psi for example. Regardless of the oil filter tree. The guys that have super high oil pressure, over 100 for example will have a modified oil pressure releif valve, double spring, shimmed, disabled etc. Oil filter bypass is a different thing entirely. That's to allow unfiltered oil to flow through the motor in the event of a blocked filter. The tt filter tree has an extra pressure valve in there that opens at a certain pressure to allow oil flow to the cooler. For most street cars this is all that's required. So no a stock na zed will not have oil pressures at 100 psi regardless of where you measure it. Most stock vg engines will have approx 20psi hot idle oil pressure with oil of similar viscosity to recommended. Anyone who is seeing 50 psi hot oil pressure at idle will have modifications to the oil system reduced oil flow to the heads if solid lifters are fitted for example. Or be using an engine oil much higher than stock
The bypass valve I referred to is the filter bypass valve I had mentioned before. I was most probably ambiguous in describing it. Every car ever made (save for those fitted with FULL FLOW filter setups) has one as pleated paper oil filters are unable to pass sufficient oil in one pass to adequately oil an engine and the stsyem is setup so that bypassed oil from the filter oils the engine. Interesting about those oil pressure figures tho. As a matter if interest, my NA runs cold in excess of 100psi and about 75 psi hot and idles at around 45 psi hot. just saying is all! E
