Serious Talk: Series II Renny in a Series I
 

I plan on keeping my 8 for a weekend/track car for a while and getting a DD fairly soon. I know the idea of a Series II in a Series I has been tossed around but i would like to start planning this to see if it is feasible. The idea of a Series II pumping clean 2 stroke through a SOHN (not available yet for series II I know) is very appealing to me in terms of longevity.

Parts needed (feel free to add)

1. engine
2. ecu
3. harness
4. cluster
5. DSC?
6. Power steering control unit?

What is your perceived benefit?

nothing really that special about Series II.

sure they made quite a lot of updates. The biggest one I see is the new E-MOP. Finally Mazda can get rid of the old system :)

but again, I can just premix every tank so its nothing really that big deal for me ...

and the swap is just not worth it, you might as well buy a new S2 :)

Longevity mainly. I know it's a bit early but I have yet to hear of a well maintained series II motor popping prematurely. So I figure why not start looking at this now. I mean I got 77k out of my second motor with meticulous care but I like the OMP changes and Oil system revisions on the series II and to be honest after removing my oil pan and seeing the way the silicone dripped from between the housings, I don't have a ton of confidence in the reman I received.

Yeah price may make it not worth it but that is TBD. I doubt a salvage yard will know there is any difference in the engines, etc. and if you have cash in hand they will deal. Premix may be the answer my friend but that has not been proven by any stretch and series I's that ran premix have failed whereas no Series II's have failed that I know of. I'm not sure how many RX8's they have to sell to pay for a whole engine reman plant but I am sure it's quite a few.

Personally I think the changes as a whole to the Series II were done based on testing mazda did and I doubt they want to relive the problems of the series I, it had to have cost them a ton of money in labor and parts as well as brand damage.

With the price of SII RX-8s so low, you might as well buy one and just sell your S1. It's a bit pricey, but I did it.

I figured that for the $6k extra I got four years of additional use (had ~40k miles on the 05) plus all of the updates and you don't have to deal with any labor intensive swaps.

The styling update is what sealed the deal for me. Plus I love the fact that it is going to be extremely rare. (Well, already is)

good thinking

Yeah, that is definitely and option, just not nearly as fun. The satisfaction from a successful swap is awesome.

True. If you plan on keeping it forever I wouldn't hesitate at doing something like that -- but as a buyer, I don't think I would want to even look at a car that someone did this on. Resale would (should?) be much more difficult.

wouldn't one of the drawbacks be that you couldn't run an AP?

I think many car enthusiasts, especially the younger ones, have this super car mentality. They want the best, most advanced machine with the latest and greatest after market upgrade or factory update hoping to make their car outlast and out perform previous bench marks. It's all ridiculous to me. For Christ's sake, it's a damn car. So what if the Series I may or may not have better oiling capacity over the Series II. It ain't gonna make the car go any faster and I suspect only marginally provide better oiling capacity. Appreciate the car you got for all its quirks and peculiarities.

b 'Eight': proper lubrication in the engine is and has been an issue for the Series I RX-8 since it came out. The fact that it is one of the few changes Mazda made to the S II is a testament to the fact that Mazda has realized there was a flaw in the Series I and is trying to address it.

I don't think 9k is doing this to be faster or have the most advanced car but to take advantage of the changes Mazda made to prolong the life of our engines

Resale is shit on an 04' modded Touring with 110,000 miles regardless of how clean it is. My car is worth $7,000.00 give or take.

Yes, very good point I hadn't thought of.

Exactly.

I could drive an Enzo and I would still wanna mod it. I always have modded my cars and I always will. The 8 is far from the fastest car I have owned. I guess I just like to mess with shit. Some of my ideas have panned out and some have crashed and burned, it's fun.

I believe it to be a good idea. I am also trying to save some money to buy a salvaged S2. I'm going this wrought so as to swap out the tranny and rear diff too. If you are intrested go to this website and check them out for yourself. I've been waiting for an 09 to pop out but hasn't yet.

www.copart.com

I wouldn't bother with a S2 engine swap. Since you will be mainly tracking the car, eventually you will start looking into power upgrades and stuff, might as well save up to go bigger 20B or something while you hone your skills on this engine. Plus I don't think tuning shop would bother with the s2 engine anymore considering the sales of s2 is dying down and ending soon so not much upgrade potential compared to going other routes. Just my opinion.

Not sure. But. You might want a new TCM. (Transmission Control Module) Mr AT.

Waste of time and money.

Instead, just take your "series I" motor and swap out the housings for a pair of new "series II" housings.
Add two more metering jets, have someone fab a distribution block to expand the 4 lines into 6 and call it a day.
There is nothing else of value in the newer motor.

It's certainly a good topic to kick around and I don't want to play the "it can't be done" guy because we all know it can be.

However, one of my primary focuses is working within the confines of personal budgets with a project that will reap benefits on par or beyond what the costs are.

If you're looking to turn your RX8 into a track vehicle there's one thing you are going to want which is reliability.

I've refrained from exploring FI because I daily drive my car and I cannot afford (financially or emotionally) to deal with constant problems brought on by pushing my RX8 to the limits. Maybe one day when it is the weekend toy but not today. When I go to the track I can spank the shit out of my car and never once have any problems. I've never had to do any work on my car at the track (knock on wood).

So, with all that you need to ask yourself whether you are willing to put up with complex issues with little to no support to help you troubleshoot. If not, then I would pass up this idea right now.

Off the top of my head you will have to deal with a new instrument cluster, new PCM and also the fact that you cannot tune it with the AP. What longevity benefits you might get you can get with a well built Series I motor.

There will be zero performance gains which really makes this totally uneconomical. It's one thing to do a motor swap that will net major gains in performance over the stock motor but that's not the case here.

You can easily obtain the longevity you're looking for by making sure the motor is built well, has proper lubrication and a good tune. You will be able to go to the track and enjoy yourself instead of dealing with complications.

I agree with Jeff, especially since the main differences rely on the OMP and the oil pressure.
With maybe 300$ worth of parts and labor you could update a S1 engine to respect those standards and then some like adding an e-shaft bypass pellet, lovely underlooked longevity mod if you do short trips.
With the price of the swap you could buy a properly built block with a lot of nice little add-ons like balanced injectors, slightly ported\polished internals, tight clearances etc. I know that you're not going after power with this project but you would get a reliable engine that outlasts the other s1 engines while having a better and broader powerband.

Totally agree with yall---it would not be a complex swap at all. Just use the series 1 intake and injectors etc then a different distribution block for the omp. Thats it. Used motors can be found. you will have the bigger oil pan with its different design and increased capacity,
dip stick in a better position, oil filter in a different position, increased oil pressures with different internal oil flows, better water pump and the extra oil nipple.
IMHO its the way to go.
OD

The 12A's are VERY reliable....just saying! :p:

I would be happy with 230WHP, I also don't need a tuning shop I will do everything myself that I can.


This is something to research, have you given this serious thought? maybe in Vegas you BHR guys can enlighten me on the possibility of this.

That is true, I will have to budget and see if the cost of properly built Series I is the way to go but the problem is that they don't seem last on the track no matter how they are built. And by last I mean make as much power after 100,000 miles as it did at 10,000. If I could get an entire wrecked 09'+ I could likely make money back selling the other parts I don't need. Thanks for the input.

Good points on a properly rebuilt motor. This would be a canyon run/track car only, no short trips. I am likely going to buy an E46 for a daily.


I would like to discuss modding the Series 1 to see how feasible using the S2 housing, etc. would be. Wouldn't the PCM be a problem since it is not setup to use the additional oil injectors?

no it would not as the total volume used remains the same between the si and s2 as i understand it? All that would happen is that you are diverting the s1 omp output to 6 nipples instead of 4. Thats it.
I have a feeling that once the 09+ engine start getting disassemble more, more things are going to be found that are changed from the S1? I dont know for sure, but I would not be surprised.
Like MM has said also--the s2 shortblock(manual or auto) is a bolt in except for the omp needs 2 more lines.
OD
OD

No - mechanically they are identical.
All they added was the oil injector boss and changed the oil pressure regulator.
Everything else is an accessory.

Hmmm, so what role does the ECU play in oil delivery and control of those injectors?

Hasnt the oil pan and the internal oil flow been changed somewhat due to the reposition of the oil filter and new omp system etc?
I understand the clearances and internal parts are the same.
OD

I need to correct myself---I now dont think the S2 engine can be used in the S1 car as easy as I 1st though. No where to mount the S1 omp and I dont even think the front plate can be interchanged?
The S2 omp oil nipples are different and the S2 omp operates them under pressure(7-8 psi or so), unlike the S1's.
Sorry for any hope confusion I may have caused.
Course you could always premix?

umm... let me see..........

1920 units sold 2008
1920 units sold 2009
750 units sold 2010

x20% =1147 potentical customers on the forum that may or may not have a problem

half of those may have 40k miles

So your sample of series II is very small

There's well over 100k sold on the first series.

Any comparaison is not valid unless done under specific controlled condtions.

There are not enough series II sold to make the claim it is so much more relable.

The reason I say "so much more" is, one needs to see a significant reliablity increase.

The ECU Controls ALL the Oil Injection from the 2 EMOP's..in S2

Not sure what you are going to do about your SOHN Adapter so you can use "fresh oil" for metering??..how are you going to do that?

The Front Housing is all new in S2, the Oil is supplied direct from Oil Pump , then to OCV Oil Control Valve which is internal/external on top of front timing housing, then to EMOP's.

Remember the OCV and Oil Pressure Switch/Sensor on one EMOP are also ECU controlled.

Unless you swap out everything, including dash I can see you getting many CELS and warning lamp issues...

Other things off the top of my head...
Both rotors now have knock sensors..
Power steering module and rack have changed...ECU issues??..
Yaw Senors have changed....ECU issues ???

Well............... Any good news?

The good news is that this thread received the RE-t@rded stamp of approval

Okay, so if we swap the motor, harness, ecu, and cluster. Not sure about the yaw sensors or rack but by that time a new rack might be a good idea in there are no mounting issues. So I guess Richard Won't be developing a SOHN adapter for the S2.

How can he?, there is NO resemblance between the two systems. S2 as I have said previously is completely different in Oil Delivery, Oil is supplied Directly from Engine Oil Pump via the OCV to two external EMOP's that sit on top of rotary engine. Even the 6 Oil Nozzles are a different Design and Unit.

I mean create a whole new adapter. I need a visual. Off to find pictures.........

https://www.rx8club.com/attachment.p...1&d=1276128718


Jeez mate this has been done to death before...;)

Sorry I don't have a color pic...hope this will do..

Oil from OIL Pump goes to OCV Valve (see ontop of front Cover), the OCV is basically an oil distribution and
soleoid device (the exact same part is used in some Mazda Banger engines) to supply oil to the two EMOP's
and for cleaning mode of Oil Tubes.

Oil goes to the two EMOP's (#1 EMOP has the only Engine Oil Pressure Sensor on it), one does 4 injectors the
other does 2 injectors, from there a Oil Return Hose goes straight into the Oil Filler pipe back down to oil pan.

The engines OIL Pump maintains Oil pressure inside the EMOP's Chambers between 7 and 20 PSI.

So basically, I really do not know how any adapter can be fitted without serious CEL issues as this is all controlled by ECU (PCM).

But one never knows..

I guess for those who want to have an external (clean supply of 2 stroke oil) tank would have to pressurize oil and
supply to the two EMOP's somehow and also blank off the OCV location.??:)

What does one do about the OCV Solenoid wiring if you remove and Blank the Valve off, would it cause a CEL??..
there is a diagnostic code for it...do you want me to find it?

Just intercept the OCV with a pump operating off its own reservoir.

How do you stop any CEL's, or Trouble Codes?

There is no AP for S2's..

Why would there be a CEL?
The EMOPs will see the same oil flow, its just coming from somewhere else.
Use a pressure accumulator and a low-pressure oil pump.

/\ The risk of failure would outweigh any benefits of being able to use two stroke oil IMO

New Codes for S2 Oil Metering, Not Applicable to Series 1.

P0522 Oil pressure sensor low input
P0523 Oil pressure sensor high input
P1680 OCV circuit low input*
P1681 OCV circuit high input*
P1682 Metering oil pump No.1 circuit low input*
P1683 Metering oil pump No.1 circuit high input*
P1684 Metering oil pump oil pressure sensor –oil pressure is low*
P1685 Metering oil pump oil pressure sensor –oil pressure is high*

* Dash Oil level warning light flashes

P0522 Oil pressure sensor low input
�� The voltage of oil pressure sensor input terminal is less than 0.2 V for 0.5 s or more.
P0523 Oil pressure sensor high input
�� The voltage of oil pressure sensor input terminal is more than 4.8 V for 0.5 s or more.
P1680 OCV circuit low input
�� The PCM monitors input voltage from the OCV. If the voltage of the OCV input terminal is less than the
specification for 1 s when the battery voltage is more than 10 V, the PCM determines the OCV circuit voltage
is low.
P1681 OCV circuit high input
�� The PCM monitors input voltage from the OCV. If the OCV current is more than 3.5 A for 2 s when the battery
voltage is more than 10 V, the PCM determines the OCV circuit has a malfunction.
P1682 Metering oil pump No.1 circuit low input
�� The PCM monitors the input voltage from the metering oil pump No.1 when the battery voltage is more than 8
V and the metering oil pump No.1 control signal turned from ON to OFF. If the input voltage is less than the
specification, the PCM determines that the metering oil pump No.1 circuit has a malfunction.
P1683 Metering oil pump No.1 circuit high input
�� The PCM monitors the input voltage from the metering oil pump No.1 when the battery voltage is more than 8
V and the metering oil pump No.1 control signal turned from ON to OFF. If the input voltage is more than the
specification, the PCM determines that the metering oil pump No.1 circuit has a malfunction.
P1684 Metering oil pump oil pressure sensor–oil pressure is low
�� It is that the oil pressure at the metering oil pump system is less than 40 kPa {0.41 kgf/cm2, 5.8 psi} continues
for 10 s, after specified period passes after the engine starts.
P1685 Metering oil pump oil pressure sensor–oil pressure is high
�� It is that the oil pressure at the metering oil pump system is more than 180 kPa {1.84 kgf/cm2, 26.1 psi}
continues for 10 s, after specified period passes after the engine starts.
P1686 Metering oil pump No.2 circuit low input
�� The PCM monitors the input voltage from the metering oil pump No.2 when the battery voltage is more than 8
V and the metering oil pump No.2 control signal turned from ON to OFF. If the input voltage is less than the
specification, the PCM determines that the metering oil pump No.2 circuit has a malfunction.
P1687 Metering oil pump No.2 circuit high input
�� The PCM monitors the input voltage from the metering oil pump No.2 when the battery voltage is more than 8
V and the metering oil pump No.2 control signal turned from OFF to ON. If the input voltage is more than the
specification, the PCM determines that the metering oil pump No.2 circuit has a malfunction.

So I guess if you can fool the PCM when removing the OCV so it does not see a Low or High Voltage.
AND you can maintain Oil Pressure between 7 an 24 PSI (about) with a "new" external 2 stroke oil supply, then you won't have any CEL's or warning lights flashing..

WHY EVEN BOTHER...

^^ So, we set up our accumulator for 20 PSI.

And what, exactly, would we be facing as a failure mode? Its not a particularly complicated thing I'm proposing - certainly no more complicated than the Sohn adapter in it interface and the current system in its implementation.

Personally, I don't know why anyone would bother.

Just do your next "S1" rebuild with "S2" housings (that's all that's available anymore, anyway) and service the three nozzles with the "S1" OMP with a splitter.

Are there really any other "benefits" to the "S2" design?

^^ You left off the OCV removal and it's circuit

I wouldn't remove it. It just wouldn't be doing anything effectively.

AHH...BULLSHIT!! ;)

S1 and S2 Rotor Housing are separately available and do not supersede from S1 to S2.
According to 2 on-line US Genuine Mazda Dealer Parts Suppliers.

N3H1-10-B10C Series 1 R Housing $703.39
N3R1-10-B10 Series 2 R Housing $776.30

You missed my point.

You can't get S1 housings right now because there was a stop-work order. They are only milling S2 housings. The only S1 housings are whatever is already in the retail chain.

Stop work order...what a load of BS..

You said they are Not available 'Anymore' which is incorrect..again.

Firstly if Mazda did supersede the housings they would supply as part of the super-session a blanking plug for each housing (if they are used on a standard S1).

Second, I am not 100% positive the S2 (N3R1) housings have the same thread type/side to take the S1 Nozzles, as the S2 nozzles are totally different and the only thing the same is the crush washer, so one would assume the internal thread in housing is the same and the oil hole in the housing is the same.

But you know what they say about assuming.

It is. It's pretty annoying.
We've been trying to get them over here, but they haven't made any since October of last year (October 17th, to be exact).
Even Walthall is dry.

Anymore. Meaning any more.
Should they start to make them again for some reason, then "anymore" wont be valid at that time. Until then...

Plus, I don't see why you keep using the word "supersede". I don't think it means what you think it means.
The new part number didn't "supersede" the old one, it is just the next iteration. The old part number is still valid. There just aren't any more of that part available.

I don't see why you continue to talk about something that you know absolutely nothing about..so you own an RX-8..your first one, and you are on your 4th engine, and??

Supersede means "to take place of", the Series 2 rotor housings DO NOT Supersede or 'to take place of" the Series 1 as you suggest or think you know.

If the old part number is still valid...it is still in USE as a replacement part, just because it MAY be out of stock and on back order with the factory MMC (Japan) where they are made, does not mean that the part has been replaced by another, in this case the Series 2 Rotor Housings YOU Think for some reason in YOUR MIND will be the replacement...or "next iteration".

Anyway..I have had my Fun with you..:D: