My reading of the experience of others is that Rennys seldom, if ever, fail due to bearing wear. They tend to run either too hot (blown coolant seals) or too cold (milky oil). The OMP system is lacking center injectors, were set to supply too little oil in the early cars, and the hoses/tips are prone to plugging. The seals are prone to carbon-fouling compared to PP 13b's.

None of these issues are fixed by heavier weight oil or higher oil pressures. I agree that 5W-20 is probably too light. I use 10w-30, but don't run in winter and our summers are on the cool side. The OP was asking about the experiences of those using the high pressure mod, which I provided along with the rational for doing so. I apologize if I seemed abrupt in my "nope" to 20w-50; I was thinking at the time more along the lines that the effect of using it is not the same as the effect of the oil pressure mod, not that it is bad for all people under all circumstances. Racing in Arizona, yeah, commuting in Alberta, probably not. If anyone holds the 'key' to guaranteeing longevity in these things, I've yet to see it. (Though perhaps using 5w-20 with no oil or filter changes after 50k miles is a way to reach 140k as was the experience of a poster in another thread.)

YMMV

 

So what is the bypass pressure rating in the series 2 filter?

Looks like a filter relocation kit might be something to look at then...

 

you can't ever see much when your head is buried in the all the wrong assumptions sand

 

when bearing/e-shaft clearance is out of spec, there will be more wear on the apex and other areas.

it's a well know problem. especially when people don't give a **** about their cars, which is fairly common in US. Just 2 days ago a BMW X5 that was going up the bridge next to me in traffic blew his radiator, steam came out. fun stuff, I can heard the "BOOM" even when my windows were closed. I was looking at his car and like wtf ur **** ******* blew man, u can even see steam coming out from the hood. but he was STILL trying to drive it. well, that didn't go too far cuz it was steaming like nuts. great example of ppl don't give a **** about their cars.

as for too cold, it's bad for every car. not just rotary, again, ppl don't give a **** about their cars.

Driving used to be a luxury thing, something u should enjoy. but nowdays, wayyy too many ppl that's not supposed to drive are actually driving. totally kills the enjoyment.

These injectors clog no matter what, it's not just a 13B-MSP issue. my FC had clogged up injectors too. god knows how long has it been like that. I gotta give it a good spray of brake cleaner before it flows again.

too little oil is Mazda's fault.

as for center injectors, it's mazda's fault agian.

Don't know about that. but MSP has more side seal issues than Apex seal issue.

agreed except the bearing issue, which could be solved if you use a heavier oil in the first place.

just like any other things in life, some people got really lucky, 140K without changing oil. I just feel sorry for his engine, cuz it can probably go over 250K with oil change.

 

I run the Prosport oil filter adapter plate as well with no issues at all, just do as hiflite outlined, takes two seconds. A relocation kit just gives you more potential points of failure. I have learned the hard way, K.I.S.S.

 

ASH8 knows and has posted - can't find it now.

There is another huge thread on the subject. My step-by-step is part of that: https://www.rx8club.com/showpost.php...postcount=1180

I briefly looked into relocation. The RR kit anyway doesn't come with the "stock" thread size and I chose not to use anything but the SII filter.

 

Good point.

Bad maintenence can be make things worse of course. However, many here have suffered blown engines even with good maintenance. My ~110 hp 1978 RX-4 ran over 100k miles being treated just like an ordinary car (with more frequent oil topoffs). The first couple of RX-7 series had a similar reputation of robustness. (I don't know enough about the FD and FC to comment). I'm told that all ran with the higher oil pressure. Mazda didn't have to create a 8 yr/100k warranty for them, nor set up a small factory dedicated to rebuilds. It seemed reasonable to take my Renny to the higher pressure. Will it work? Haven't a clue, and especially so considering there are so many other issues to look at with these engines.

My DD gets started every work day all winter, put in gear immediately, driven 3 miles, parked for 9 hours, driven back home, and cold soaked overnight. 162k miles, oil changed no more than 2x/year, timing belt/water pump at 125k miles, original coils, fuel pump and, so far, one new set of spark plugs. Odds are it'll run another 162k unless it turns to rust first. No way I'd try that with an RX-8 (though I would, and did successfully, with my old RX-4).

Oil pressure mod, oil weight increase, aftermarket coils, etc, etc, is all working on the margins of an engine with problems designed-in at the factory. One can see where they realized the flaws were by what they fixed with the Series II.

[/quote]

 

Older rotary engines except fd are very reliable.

I dunno about fb and older but for fc na, it can go over 200k miles easily and turbo ii models can go over 100-150k without too much problem. If the engine is build with viton seals and fd corner springs, their life will be significantly longer, cuz its usually the soft seals that gives out first, then its the pathetic wire type corner seal springs.

Fd had much less than optimal reliablitiy, factory build stock early engines can give out as soon as 60k miles. Mazda made some changes later so the engine last longer, but most still needs an overhaul around 100k miles. Part of the failure is due to the crappy cramp up design in the engine bay, poor cooling. 99 spec improved it a lot, plus a twin turbo that flows better. You can get those parts here from mazda, but its not cheap and most ppl just stick with their own cooling mods. Thats also why ots hard to find a complete stock fd these days, but its easy as **** to find a completely stock fc.

 

Back to oil pressure.

Mazda is so stupid on this issue, its well known fact that even fc is under pressure from factory at 70 psi, and they are doing it again for 13b-msp, which is the highest output na engine with a holy moly 10 ish psi increased ...

Well at least they know they f up and fix it in s2 ... plus a few other fixes, but damages have been done there is nothing they can do to reverse that. *sigh*

Lets just hope they will not mess up the next one. Jeeze

 

No I don't ...but I can take a guess....let me see.....ummm

S2 Oil Filter By Pass rating is 20.3—26.1 PSI
S1 Oil Filter By Pass rating is 11.4—17.1 PSI

 

What does that kangaroo guy know about oil pressure and rotary, the sushi guys knows best!!!

 

Just use a non-bypass filter and be done with it

 

That of which the part number and manufacturer would be...

 

I use a Canton Racing filter on mine....1 micron filter I think ...much better than the 15 micron that most filters will let by

 

I will start using those when my bank account is replenished I looked those up on your recommendation before, the initial price is kind of high but not too bad in the long run.

 

No bypass + plugged filter = no oil flow. (Or the filter element rips)

Unlikely to happen, but ...

 

ok, lets stick to the facts, help us out here:

S1 oil system flow rate: ?
S2 oil system flow rate: ?

S1 oil system differential pressure across the oil filter when new: ?
S2 oil system differential pressure across the oil filter when new: ?

how do you ever know if your filter is actually in bypass mode or not?

what we have here is a bunch of moron's pretending to be engineering experts using nothing more than assumptions pulled out of their @ss as the basis for their insisted expertise

 

Unless you grenade threw engine...or don't change the filter for 50000 miles...the bypass it's basically a formality...

With the capacity if that filter you don't have to worry about it plugging up

 

As a practical matter and with the big filter, agreed.

 

what's going on here is no different than this thread starting at Post#108

https://www.rx8club.com/showthread.p...53#post4207153

all the wrong assumptions and assessments ...

 

I am surprise none has reacted sooner.

The main reason the S2 Oil Filter has a higher (50% max) by pass trigger is because all the engine oil from the new Oil Pump goes through the Oil Filter FIRST, it can not be diverted at any stage like all previous Rotaries can via their rear OP Relief Valve, where at higher RPM/Loads can return some unfiltered oil to Oil Pan before it even reaches the Oil Filter.

IMO the main reason the S2 Oil Filter was made 25% larger is because Mazda obviously found a longevity deficiency with the smaller 25+ year old one they once used...when you crack open both (OE which I have done) the S2 filter cone is longer therefore larger and the BP Spring Plate is slightly thicker. Most 'other brands' of S1 Oil Filters use a coil spring, not a tension plate.

Perhaps Mazda found that after a short period of use/age the original S1 Oil Filters were going into by-pass early?....it is a possibility...and I agree no one knows if and when their Oil Filter goes into that mode.

 

Ash, think about the service intervals for the eu market for a while... oil change every 12k miles\20k kms...

 

Also everyone seems to forget that the bypass pressure is the differential across the filter media....not the actual oil pressure

 

you guys ... AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH

*runs to my 8 and kick it hard*

 

who is a moron?