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.