Tom-Guy

Goforth has a Microtech, which rotary **** love, that he'd probably sell.

SkunT

holy jesus. I just read what you said a little more closly. hx55

you realize that you cant just put an extra 6psi on a rotary. Thats a HUGE difference, especially on a holeset. lol. and then on a air fuel hack on top of that.

from what I know of rotaries, you cant really tune a rotary for 13psi and then just run 6psi on the ******.

yeah, id forget about that throught.

Aaron Cake

He was seeing full boost on the stock turbo at 3K? There was something wrong with his setup to produce that much lag on the stock turbo with a high compression 6 port block.

NO! That's too much turbo for an S-AFC based setup. You'll need a full standalone, full fuel system upgrades and all the related stuff.

Ceramic seals? You're looking at about $300 per apex for a set of ceramic "racing" seals. Completely unnecessary and a waste of time on a street car.

That's nowhere near enough fuel. The HX55 comes in various configurations but for a turbo rotary, you're looking around 400HP. You'll want 720CC primaries, 1680CC secondaries and a significant fuel pump to drive it (ie. Walbro 255). Don't even think about using the stock ECU.


That's wrong.

The S4 and lower engines are well known to have weaker dowel castings then the S5 and above. It has nothing at all to do with 6 port vs. 4 port and it is certainly not dowel pin shearing. I've never seen a dowel pin break unless something really bad happened (such as an engine that experienced eccentric shaft failure at 12,000 RPM).

You'll run into the weaker casting issue if you experience severe detonation. Generally detonation will break apex seals but if it's caused by something other then too much timing or not enough fuel you can be at risk for dowel casting failure. An example would be if the EMS picked up ignition noise, something very common with the Haltech. If it picks up noise and fires the spark at the wrong point you will get massive preignition during compression which will do a dowel casting very quickly. This can often be seen in datalogs though. You'll see the RPM steadily increase and then suddenly a few logs will show some ungodly high number like 16,000 RPM. That's where the engine was roasted.

The S5 castings are stronger but not immune. I've seen someone go through 4 engines with the stronger rear iron because their wiring was ***-tacular and they had mass amounts of ignition noise.

Hell, I've been running well over 350HP on my S4 6 port engine for two years now.

Uh, yeah actually. Plenty of them...

What happened? What EMS were you running? Who tuned it? I'm always interested in reading about failures as it's an opportunity to learn.

Sounds like he doesn't really know what he's doing. He's probably on the RX-7 Club and I think I may know who you're referring to.

How is this relevant?

First, the stock components were designed to run the car in stock configuration. Start cranking the boost and you are now past what could be considered stock. Second, saying "just a boost controller" is a bit of a misnomer. Stock boost is around 6 PSI (actually it's 5.6 if I recall correctly). A boost controller can raise it to the turbos practical limit of 12 PSI. So yes, if you double the boost, the ECU isn't going to be too smart about what to do regarding fuel. Considering the ECU has a factory programmed boost cut of 8 PSI and you need to defeat that to crank the boost, I think it's pretty clear that Mazda was obvious they intended the cars to run a certain level of boost on the stock system. The saving grace of the stock system is that it runs so rich under boost that generally a fuel pump will get you to around 8-10 PSI, depending on the characteristics of the car. After that a larger set of secondary injectors will be required. If indeed you have maxed the AFM, it really doesn't matter because at that point you will be using a secondary fuel controller anyway (such as the S-AFC....which will fool the ECU into seeing a less then maxed AFM signal) to take care of things.

The S-AFC has it's places, but I agree with you. A full standalone is the proper way. However if someone just wants a bit more boost for little money and has no intention of upgrading the turbo, an S-AFC will do the job.

I agree, that's too much turbo for a S-AFC. That's around 400HP worth of turbo on a rotary at reasonable boost levels. Well into standalone territory.

That's an insane statement to make, and is totally incorrect. A rotary is like any other engine. What do you think a fuel map does? It supplies the appropriate amount of based on engine load. The ECU sees the engine is at 6 PSI at some RPM and fuels it according to the map, which ideally is tuned properly (yet rarely is). The ECU sees the engine is at 13 PSI at some RPM and supplies the appropriate amount of fuel from the map.

It's how an EMS works.

Tom-Guy

It's probably Phil. Last time I was around him his 10 year old boy was running around acting like a barbarian, telling grown men their cars were pieces of ----. Stevo shut the young man up by asking him in no uncertain terms if he ***** his sister, it was pretty funny.


Aaron, please post more. Thanks.

Hitchhikkr

Ok your clearly a rotor expert, so ill try not to step on your toes with my limited knowledge. All I know is what ive learned from my own experience and the experiences of those around me.

I assure you, my S4 casting streetport DID manage to sheer the dowel pin, but also broke/cracked the casting around the pin. This was about 6 years ago, and I wish I still had the pics but there long gone. Phil that JD mentioned also managed to shear one too, his car was a consistant 10sec car, and still drove it everyday. Quite a feat. He ran an E6x I believe, also tuned by Steve.

Sorry I said FC engines, but meant S4 in my head. Error on my part. Its been 6+ years since ive even turned a wrench on an RX, back then I was not aware of any 350+ s4 engines. My knowledge is dated lol. Congrats on yours though.

I was running haltec E6 at the time, the old dos based crap, but Steve Osley tuned it so, I dont think that was the problem.
The engine was fresh, and had maybe 7k miles on it.

I think you misunderstood what I was trying to say. The stock flapper-type MAF meter that mazda/toyota everybody else ran in the 80's with the denso rip-off of the bosch LH-jetronic system, can only read to a certain airflow, ie when the flapper is fully open, the ecu recongizes this fact, and automatically follows its pre-programmed 'base' maps, which dont include provisions for anything other than stock boost/airflow. This applies to all vehicles running this type system. Stock car at stock boost under the right conditions can spike the meter open, but a mod. car with more airflow 'can' hold the meter fully open. Very bad for anything sensitive to VE changes, and worse for engines sensitive to detonation. This has been known for years, and is a real problem with mr2s. I was trying to explain this in not so many words to the OP.

Its been a minute since I cared about rotaries, and honestly spending a retarded amount of money on my car/engine/tuning (yes I was young and stupid) really turned me off to them after only 7k miles of driving.

If you would like to discuss niche cars, Porsche is my realm.

Tom-Guy

Aaron, meet Rob.

Aaron Cake

I'm quite surprised you sheared a dowel pin, as did someone else you know. I've seen cracked irons but never a sheared pin except in one circumstance and in that case the engine literally split a rotor housing as the rotor smashed into it. Even that I didn't see in person but only the aftermath.

For a long time before the S5 FC, the only engines you could make power with were S4 style castings with the smaller dowel land. Plenty of those were above 350HP as well.

The S4 dowel castings are inherently weaker for sure, but it's only an issue if there is another issue that can cause damage. In my experience a lean condition is not going to break an iron. It has to be a gross ignition misfire. Not always on the cycle that causes the damage though. Sometimes the misfire occurs one cycle previous, creating massive chamber pressure on the next cycle and that's what cracks the iron.

Well there's your problem. Not to say that Haltechs are poor ECUs, but I've seen more blown engines with Haltech series ECUs then any other. Now that is partly due to the fact they are very common in the rotary world, but also due to the fact that they are very sensitive to ignition noise. I've installed a few myself and in every one I've had noise issues even though my wiring is meticulous (as in double shielded cable for CAS, always new connectors, separating different tasks into sub harnesses, etc.). Most of the time the noise can be tuned out buy adjusting the trigger gains but often it only shows up at high load in high RPM, exactly where you DON'T want to be troubleshooting. I've never popped an engine but I've witnessed plenty of others, all using Haltech. Look at the datalogs and there's a few records that show RPM spikes to 16K. It's like 6000, 6090, 7120, 16000, 16000, 7300, 7430, etc. And right there is what popped the engine. I think their reluctor conditioners are very poor. Certainly in the E6 series they were and it was a well known issue. But to make things worse there doesn't appear to be a noise filter in the firmware.

Meh, I don't know anything about Porsches. However if you want to talk DeLorean...

Tom-Guy

You have a dirty Volvo fetish.

Hitchhikkr

Makes sense. I really never held the Haltec in high regard anyway, but Steve insisted on it, so. Its ancient history now. After I sold the car the kid promptly put it through a tree. Sucks but such is life.

There happens to be a disturbing RED deloren running around the area, owner appeared to be a typical redneck, so he probably thought it was a camaro and spray bombed it. Sad really.

2GeclipseRST

My goals have changed a good bit since i've pondered my six port turbo.


I'm talking with SEVERAL people trying to figure out the best way to get it done. Went to see my tuner zac yesterday while scalping his baller old school rims from him and then trying to put the squeeze on him to sell me his apexi gt exhaust for next to nothing.... He said he's done several six port turbos. He owns an fb and an s5 turbo FC. He used to work for intense motorsports in charlotte, NC and rotorsports racing (rotary shop, obviously) in Kannapolis, NC so when he speaks and suggests, i listen.

He's done several safc tunes for customers who wanted to use one and a good bit of those engines are going good. He did however pop a 400+ hp rotary using an safc. It was his though and it was a no-risk type of deal. He knew it was going to blow up but it was for fun.... However, we spoke of holsets and says an hx35 is what i should look into along with a good, big name brand wastegate to control boost. As far as engine management, he said we should be able to pull a few degrees of timing by rotating the cas a tad and i may be able to go with chipping a TII ecu with rtek, set for stock 550cc primaries and aftermarket 750cc secondaries. He said i could run an safc with this setup to control the 750's better but rtek isn't that much more expensive. He's on speed dial so i'm sure i'll call him before i do something stupid. Fuel will be handled by a walbro pump. More or less it's trying to figure out how we're going to control the engine within a budget that's a pain in the ***. I'll definately be looking into water/meth injection for more protection during "spirited" driving aka cranking up the boost to say 10 or 11 lbs. Probably not necessary as long as i have a good tune but i'd rather have it and not need it than need it and not have it.

Out of simplicity, i could run the following:

T2 stock turbo and manifold
Stock TII fuel pump, injectors, ecu, maf, and boost sensor
Stock TII intake manifold with the lim portmatched to the N/A block.

That would get me by for a while. Zac even said i could still retard the timing a bit via cas, and play around with an safc with this setup if i wanted to but would still need to keep my egt's and afr's in the safe zone. He's got a wideband at the shop but i'd still like to have one of my own in-car.

Aaron has been more than helpful on the subject as well as kain and my buddy josh. Josh has an FD with a single turbo conversion on an rew so he doesn't really count. Lol. His car ***** all over my fc!

Aaron, i had no idea about haltech being sensitive like that. Thanks for the info. I'll try to stay away from it. May possibly go megasquirt if rtek wont fufill my needs. The tuning. Pfft. I leave that to people that actually know what they are doing. The rest of the car is easy.