9krpmrx8

iTrader: (46)

Yes I would like to know as well,

ASH8

Hi OD, and Possibly Yes..

Keeping in mind I think 9K monitors his OP from the base of Oil Filter which has shown an increase, and this is after the rear By Pass Valve (which have been shown to be not the most accurate piece of engineering) as much also depends on Oil Viscosity and Temps.

I think 9K was going to do a test (drive) and compare PSI numbers with what he took back a few months (weeks) ago at various RPM's and Speed.

If these have not changed then yes, he would have to Mod the Rear Valve, will be interesting to see the results..

madcows

That is an excellent idea! Besides for the integrated ATF cooler, do you know if there are any other major differences? Size? Capacity?

In my case, and what you mentioned, driving the car hard to warm up the oil is a lose/lose situation. You don't want to drive it hard while oil is cool, but you can never get the oil to warm up if you don't drive it hard. Lame.

madcows

I think it would be very interesting to know the OP in front of the coolers. It's obvious that they're going to pose some restriction to flow, but it's hard to visualize why the exit pressure would vary considering the oil volume from the pump is fixed at any given RPM - unless the OP in front of the coolers is substantial enough to open the front bypass.

ayrton012

I experience the same.

That has to be the case, but I can hardly imagine that the original system has such higher resistant against flow (pressure).

madcows

While I can't quantify just how inefficient the stock oil coolers are, I'm not really that surprised that a single high performance cooler is that much more efficient.

It's been suggested that the front bypass is not supposed to open unless in the event of a significant obstruction in the cooling circuit. I'm really curious as to how true this is.

9krpmrx8

iTrader: (46)

Okay guys see my single oil cooler thread for the data.

https://www.rx8club.com/series-i-tech-garage-22/single-oil-cooler-185476/page2/

ayrton012

I was sceptic about that the rear regulator can not keep the max oil pressure in the engine around its opening data, in these single cooler system.

NOW I FOUND THIS: (attached picture)

The rear regulator opening pressure is 92,5 PSI !!!! The information comes from the European Service Book. We beleived that this data is 74 PSI, until this time.


It is answered the question why PhillipM and 9krpmrx8 has 90 PSI max oil pressure in their modified oil cooling system. Otherwise it proves that the factory coolers-pipes system restrict the oil pressure so much that the front regulator opens earlier than the rear one.

olddragger

iTrader: (3)

good find and thanks-- looks like it starts opening at 78 and is fully open at 92?
So at 92--maybe almost no oil going to the filter?
OD

bse50

Wonder why i never see pressures above the 5 bars mark then...

9krpmrx8

iTrader: (46)

Can someone explain how the bypass on the filter works. I always though the oil was always being filtered to a certain degree. I am confusing myself.

EricMeyer

We typically see 90 psi measured at the stock oil filter location when running WOT. Additionally, I have never seen or heard of a bearing related failure. We experimented with Calico coatings on the bearings and later stopped because we beleived bearing related failures was a non-issue.

I am talked to some very smart people and they've offered that the 09 motors run upwards to 150 psi. The belief (an assumption) is that this higher pressure may reduce rotor wobble). Who is to say for sure.

9krpmrx8

iTrader: (46)

Cool, are the Series II motors being used by teams yet?

madcows

92psi is the pressure the filter WILL be seeing.

madcows

And another thing - 90psi isn't being seen until he's nearly at redline. If you're seeing that pressure a lower in the rev range, then there might be cause for concern. You FI guys would want to kick it up a notch, of course.

I'm still thinking about omitting the front regulator - especially with a less restrictive oil cooling system.

PhillipM

We're seeing 85-88psi by about 6krpm, then it just creeps up slightly to about 92-93.

9krpmrx8

iTrader: (46)

Yeah the 90-92PSI I am seeing is between 7,000-9,000RPM's. So if less oil is being filtered at that point I don't see it as an issue because you don't spend a lot of time there. Plus, I change my oil like clock work and many times before 3,000 miles. FYI, I am running Mobil1 0W-40 because of the poor UOA my Castrol 0W-30 showed.

ASH8

Funny how Pineapple says their Mod goes from 68 to then 88 PSI, sorry I don't trust these European books Ayrton.

http://www.rebuildingrotaryengines.c..._Oil_Regulator

Obviously you may be seeing higher PSI at WOT, the majority of Owners here do not race their car, the Renny in most cases 'lives' around the 3-4000 RPM.

ASH8

Your Oil Filter is alway filtering Oil 9K (remember FULL FLOW), it is only if you don't regularly change it and it becomes blocked, if it can't filter it starts to by pass the oil filter.

Again, feel your Oil Filter, it starts to get warm to hot almost immediately.

Sorry, don't know exactly how that little valve works.

9krpmrx8

iTrader: (46)

Cool, that's what I thought,

olddragger

iTrader: (3)

the oil filter pressure relief valve in principle opens to insure oil flow to the engine in cause of a filter blockage. If there is strong engough blockage that causes the oil to not past through the filter medium then it can take the path of least resilance through the relief valve.
thats all it is.
BUT--- with the higher viscosity oils we are using and the increased flow that we are trying to obtain it may be wise to use a filter with a higher releif pressure that the pre 09's have?
I am not sure of what the flow rates of filters are. We want more flow and pressure to be sure but we also want to keep filtering!
Eric appreciate you coming in. We have seen a lot of front stationary gear wear at the power pluse point on the engine. That and trying to understand why Mazda upped the pressures and redesigned the lube system has us all talking and searching.
I also speculated that rotor wobble had to be occuring if the front bearing was worn (through the copper) in only one section.
OD

9krpmrx8

iTrader: (46)

Courtesy of ASH8,


Oil Filter Bypass Pressure

S1...11.4 to 17.1 PSI
S2...20.3 to 26.1 PSI

ASH8

Frankly all RX-8 and RX-7 owners should be using the 09 OIL Filter..

N3R1-14-302

It is genuine Mazda Japan, and it is cheaper than ALL the other Mazda USA ones that are not Japan made.

Larger filter capacity.

DON'T FORGET A FILTER MAGNET ALSO....A MUST!

ASH8

Got to add here...

When you think of it a 11.4 to 17.1 PSI In Series 1 By Pass pressure is pretty Low, I would imagine your filter could be only 50% used or say 3000 Miles and it could start By Passing..NOT Filtering Oil At ALL.

Pretty alarming actually...

Having said that this is the same (approx) BP Pressure all rotaries have had until the S2.

RIWWP

iTrader: (2)

Is there a reasonable way to ensure that the oil is always being filtered?

You are doing a pretty good job of convincing me Ash. Is there a magnet you recommend? Or just a plain old magnet that fits?