Using Series 2 rotor housing in Series 1 engine
 

I know there is a thread about some guy in the forum using a series 2 block but he's not utilizing the third oil injector. I wanted to see if anyone has done this and still utilized the third oil injector in the middle by using some kind of separate independent metering pump? Im rebuilding an engine and planning on purchasing new Series 2 rotor housings.

No one that I know of has used it, they just blocked it off. It would also be a pretty useless endeavor.

had a long talk with mazda maniac dring a dyno day about this. yes he used s2 hosing in one of his builds and used all three oil injection holes

I wonder why Mazda's design uses two separate oil feeds for the injectors in the same housing. Theoretically, would it work to have a 2->3 split to feed the third injector?

(Yes, I know I'm ignorant. That's why I'm posing the question.)

To ensure specific flow to a desired point. Tied in together there’s no way to be sure flow is equally distributed or as intended, especially since the amount to the new center injector might be different than the amount going to the two corner injectors.


.

200.mph any info how he did it?

i dont remember how he said he fed all the oil nozzles, it was a very long very busy day. iirc someone else has used them before and plugged one hole

Or plugged them all and ran premix only (racing)

I know but does it hurt to have a third oil injector even if it's not working 100% ?

You seem overly fixated on something that you also don’t seem to have a good understanding on. S2 engines are failing early too. Seems like you might have something better to worry about than locating a magic bullet that doesn’t exist.

But since you feel compelled to do something, go buy one of the well documented premix suggestions and add 1/2 ounce per gallon of fuel with each fillup instead.



.

Ryan rotary has started doing 3 oil injectors in the housing.That engine he is using a rx7 housing and mod it to take 3 oil injectors.

Scott Rotary says that's a lot of wasted time and effort.

just go full-baller and use 5 or 6 instead ...

Probably not. The problem is, it introduces a variable that is basically impossible to figure out how to work with. How do you know whether it's injecting enough? Or too much? How is that third line affecting the rest of the system? How does it all work at various loads/RPMs/temps? Etc. etc. Can't even begin to figure this out without a lot of very careful controlled testing and teardowns. Like, this is the kind of thing that makes cars take years to develop by whole teams of engineers with lots of resources.

An S1-style 2-injector setup is a known quantity. An all-OE S2 3-injector setup is a known quantity. A 3-injector hack job is not.

If you're just tinkering and want to run it for lols, then by all means have at it. If you're trying to decide based on what "will" or "won't" be beneficial/harmful, probably safe to say you'll never find an answer other than gut feelings.

If the S2 engines are failing early its still because of owner negligence and not informed enough about rotaries. I have seen an S1 RX8 with 214k miles before it started loosing compression because the owner monitored the engine.. coolant temp,oil temp, misfires and etc. My point is everyone talks of how bad this engine is when they don't take time to know why. There's a reason why Mazda added the third oil nozzle. It's not just about lubricating but also removing heat. I was planning on using the third oil nozzle with a separate tank of two stroke oil since it burns cleaner and separated from sourcing oil from the oil pan which can get dirty and not work as effectively. I wouldn't have to premix as much or worry when in a hurry. Rotary Aviation has the oilnmetering pump adapter so looking into how that works for the mean time and see if I can use that somehow with the third oil nozzle.

The Sohn OMP adapter won't help you. It's basically a block-off plate with an alternate feed source that gets sandwiched in between the engine and OMP. The factory OMP with its four outlets is retained.

That is the excuse everyone makes for rotaries and every noobie who comes into the RX-8 world from the RX-7 world thinks they have the answer. And if you saw an S1 RX-8 with 214k is was one of maybe two and who knows it could have been on it's third engine or more and even if it were true and still running, it is probably making 100WHP at best. We have had a few new guys come into the group thinking they had a high mileage original engine only to show them the blue reman tag in their engines. My first engine lost compression at 22,000 miles, bone stock, on time oil changes, babied during break in, etc. and over the past 10+ years I been apart of many Renesis tear downs that were meticulously maintained, premixed, etc.

For me personally it has been a toss up, my factory engine lasted 22k (loss of compression), my first reman lasted 74k (loss of compression, premixed, but found faulty oil injectors when tested), my second and last reman lasted lasted 27k (coolant found in oil during routine test, was pulled before it had a chance to fail). And lastly my current and only professional build (pineapple racing on a very low (8k IIRC) mileage 2008 core) has lasted me about 40k and still has good compression and it has been turbocharged since day one.

One of our long time local guys is a tech at Mazda, has been for many years, and the S2's have been rolling in for a couple of years now. They are lasting a bit longer but the they also sold in much much lower numbers. He said the most common failure modes as far as they can tell (they can't tear them apart) are the same, just a loss of compression. But he has seen quite a few failed cats so it's obvious Mazda never fixed that issue either. The S2 is better but they still fail more often that they should and the same reman plant that makes S1 remans is making S2 remans so it doesn't really matter how many injectors they have.

You just explained what I thought no one takes the time to figure out why is it a toss up between really low mileage and high mileage.. I didn't believe either.. I bought two non running S1 rx8s both original owners. 214k and the other 134k that's pretty good I think, I couldn't find reman tags( pls inform me of what they look like to make sure)carfax checked and you can usually tell if the engine has been pulled once. Both owners were the original owners shows in carfax as well and both said it is the original engine.

Notapreppie thanks for the info I just saw it but it was giving me ideas the way it works. I also like the idea of having a separate oil tank purely for the oil nozzle.

Carfax is probably accurate on the owners but not the engine replacements. And mileage doesn't mean shit I am on my fourth and know plenty of other RX-8 owners with high mileage who are about the same. They could have had five engines each for all you know.

N00bs gotta n00b ... :)

Wow they're that bad huh? why do you guys even own rx8s? You guys always shut noobs down? Maybe I should just join the LS bandwagon...I bet they would be more supportive at least. But nah I still like these engines good or bad...I was just trying to see the root cause of these engine failures and maybe find a way to make it better even if it's a long shot.. what's wrong with that? I guess I'll get help somewhere else and I did call racing beat in aneheim and even they've seen 200k renesis and it is possible...What they say makes more sense but thanks anyways guys sorry for being a noob I thought it was a valid question and idea.

No, you’re talking about something you don’t understand to people who do. You ask a question and then argue against sound information and advise. We know and love are car for what it is. Some of us for 12 - 13 years now. You’re not doing a very good job of presenting yourself in any favorable form of understanding or enlightment. I chose to call you a n00b just to cap off the blah-blah-blah of trying to reason with you, plus we’ve seen people carrying on this way come and go here like birds on the wind. We’re having a discussion and you’re part of it. Participate and learn if you want, or not.

I own it because it's worth it. It's a car I can take to work on Monday but won't be financially burdened if I stuff it into a wall at the track on Saturday.

So, I have to shell out roughly $1.2k a year to keep it running (assuming reman/rebuild every 3 years). That's far less than a car payment.

Anyways...So you guys don't believe 200k plus is possible? You don't think 22k miles on that factory motor you had not worth digging into? There's got to be a reason for that.....

Not with passing compression scores. I think it's remotely possible (though improbable) that it will still start hot, idle hot and run normally but won't make anywhere near the same power as an engine with passing compression scores.

^ This. I have seen an engine with a broken apex start and run with an S2 starter. Sure 200k has been done (once that I know of that was proven on an original engine) but as NotAPreppie pointed out it would be way down on power and one or two cars making it to 200k on the original engine is just a fluke, nothing more.

Facts are that Mazda has replaced thousands of engines in a car that was sold in very few numbers and the reason for that is because it just isn't a great engine. The sooner people realize that and the fact that the RX-8 has little in common with older RX-7's, the better off they will be.

I also think that every RX-8 owner should go to an RX-8 dyno day so they can get a reality check.

A Honda will get you 200k easy.

Yeah my daughters 95 Accord had 230k when the cluster was replaced, we are guessing it has about 280k on it based on the previous owners records and it just floated a valve. I have had three Odyssey's for work and two were at over 250k when sold and lived hard lives but were well maintained so I am sure they are still kicking around. I also had a Sienna that was traded in at 333k or so with no issues to speak of other than the shifter was replaced. I just sold my 98' Integra GSR and it was right at 200k.

Sure it is. Just like 1,000,000 miles on an old Volvo, or winning the lottery.

The measure of an engine isn't what's possible. It's what's likely. 200k on a Renesis isn't likely. Not remotely.

The S2 should have better odds of running longer between rebuilds, but it's far from bulletproof, so the only way to tell would be with big aggregate data sets (i.e. looking at ALL S1s and ALL S2s and comparing failure rates). No one has that kind of data -- other than maybe Mazda, who obviously would never tell and likely couldn't be trusted even if they did.

Does that mean the S2 improvements were meaningless for reliability? Of course not. This may be where I part company with some in this thread (besides the unproductive name-calling and condescension). "We don't know" means "we don't know."

But either way, we're still stuck with the fact that there's no reason to expect modding an S1 engine to mimic an S2 will improve longevity. We don't even know if the S2 changes worked from the factory, let alone if one or two of them would work as hack jobs. Gotta figure, if it were that easy, why has Mazda had so much trouble in the first place?

From what I have read around here, it's unlikely to get to 200k without a rebuild, and even if you do, it's on borrowed time.

There is even a thread where an S2 owner shared his compression decline over time.

Considered S2k, but the no-practicality part really turned me off. Same as Miata.

I originally wanted to replace my Accord Coupe V6 5AT with a 6-speed version, but they are very hard to find.

If you are a MT guy, most of the newer MT Hondas aren't even worth driving without a tune just to get rid of the rev hang, and trust me, you will want to rip your hair out with that rev hang.

My s1 lasted over 10 years and almost 100k.

Got a reman. If it lasts that long again I'm fine with it I guess. Cheaper than buying a Miata or something similar.

So what is the solution in terms of keeping it reliable? build a NA RX-7 13B to make 235hp? is that worth it? Or just skip it and run a NA 3 Rotor very conservatively? or Just keep tossing in Renesis remans/rebuilding yours and hope for the best?

It will never be as reliable as a Honda. These cars are toys. Fast, sexy, awesome toys. You can get it relatively reliable, but that's a far cry from the 200k the OP is talking about. I have a panty-dropping 85 chevrolet sprint as the reliable one. (Hey, 50 mpg is some serious stuff). If you don't enjoy wrenching, don't buy this car.

And OP, the reason people are getting impatient with you, is because there is collectively decades worth of rotary experience on this forum. They've forgotten more about the rotary than you and I will likely ever know.

Then you come in here and act like you've come up with some grand solution, do you not think that if it were that simple the guys that have been doing this for so long would have thought of it by now? Not to say coming up with your own independent thought is wrong, but when they say it's a bad idea, it's probably a bad idea.

The 05 I bought has 100k and some change on the clock, original motor. When I saw that my exact thoughts were: "God DAMN, this thing was a fucking trooper to have lasted that long." Twice that, as previously mentioned, just isn't realistic. Hell, 200k is an achievement even with modern reciprocating engines.

Best thing to do is to setup your budget to spend $4k every 4 years for a quality rebuild/reman. <$100/month is still cheaper than a car payment.