REAmemiya_fan

So as I am ready to drop my 87 6port into my dd after performing some overhauling to it, I will be tearing apart and rebuilding my 88 6port. Project goals will be to make a reliable and streetable 200+rwhp. No emissions. I have never rebuit a rotary before, but I know enough that I am competent enough to do it. I know how to make easy turbo power, but I want to stay na and build something that will make or exceed my horsepower goals and still be streetable and reliable. I'm not looking for the engine to last me 200k mi, but i also don't want it to fall on its face after 50k.

What I am looking for is advice on what I should be doing to hit my goals. What I have planned out so far is:

Mazdatrix porting template for 6port
No emissions
S5 upper and S4 lower intake manifolds
Full racingbeat exhaust. Streetable header, presilencer, y pipe, extension tubes, and mufflers.
Atkins induction sleeves
Atkins master rebuild kit
AC delete (too lazy to convert to 134a)
Omp removed
Taurus 130A alt
K&N filtercharger w/ carbon cold air box with tubing feeding air to it from the bumper
Need advice for ecu

Please help me acheive this goal, thanks for all yhe feedback and help

RotaryEvolution

iTrader: (30)

add turbo port sleeves to your list

as far as standalone just about any will do these days.

that all should get you close to 200whp.

REAmemiya_fan

Should I just buy turbo housings or could i buy turbo sleeves and press them in if thats even possible?

RotaryEvolution

iTrader: (30)

they have 2 roll pins that hold them to the housings. it's not necessary to buy turbo housings if yours are in ok condition, the sleeves are swappable.

REAmemiya_fan

What would be a good budget standalone? I dont want to spend 1300 on a haltech just yet. I'm I only work part time bc im in school, so this is a budget build. I shouldve mentioned that earlier sorry.

fidelity101

iTrader: (11)

okay so first off, you cant mix the S4 and S5 manifolds, they don't bolt up.
alternator wont make you any more power
you dont need extension tubes on that setup if you have the y pipe
you wont hit anywhere near 200whp with a 6 port. trust me
the porting template doesnt even do that

RotaryEvolution

iTrader: (30)

megasquirt is going to be the cheapest but it also has probably the steepest learning curve. being that it is an n/a, that at least is a step in the right direction as it is difficult to really screw up a naturally aspirated engine.

fidelity101

iTrader: (11)

Yeah mine's all used parts, just put a rotary aviation wet seal kit in, there is also a hole in my rotor! it gets routinely flogged in the backwoods and rallycross events with no engine related issues. My only issue is a lack of power.

lastphaseofthis

iTrader: (8)

I'll go ahead and throw this out there, the Rtek S5 would be a good choice here.
Also, if you want 200k miles from this engines. you'll need NEW housings, and pretty much new every seal. probably bearings as well, if you plan on 200k miles.
You want the power? Rx-8 rotors, 6port to 4 port conversion, with port matching S5 upper and lower intake. port the exhaust closing time, not opening.
720cc injectors all around, and a 3rd gen fuel pump sounds good too.

fidelity101

iTrader: (11)

rx8 rotors wont yield you much
720cc injectors are overkill, stock ones will do fine.
3rd gen fuel pump is overkill stock fuel pump will be fine
just be sure you have a properly functioning fuel pump/injectors really...

but yes for a 200k engine, just open up a parts manual and buy everything new essentially.

REAmemiya_fan

Okay, so 200k is out of the question lol. However, port timing on the intake is just as important as closing on the exhaust. If you can open it maybe a degree or two earlier than stock as well as closing maybe 4-5 degrees later, followed up by a polish and smooth transitions, port flow should be smoother, allowing for a little better of a powerband and smoother power delivery. Then port timing on the exhaust into the RB streetable header and pre-silencer should help with flow. I know my Corksport is overkill on an NA, but it will eventually be replaced with the y-pipe and mufflers.

From what I have learned with piston engines, exhaust gasses flow far easier than intake gasses, so you can have more intake port than exhaust and be just fine. Then again I've never built on a rotary so this could be different.

As far as the injectors, I'll just be going with oem replacements or something just as good, and fuel pump will either remain stock or I'll go with a Walboro if flooding wont be an issue.

Megasquirt sounds good, I can take some learning time and actually get to know my ECU and how to properly tune it. I don't have a dyno readily available to me, but I could do some testing on my buddies 900ft driveway (everyone runs a 300ft time/speed there for bragging rights).

I want to keep the 6-port setup, I believe it is better for a street setup than a 4-port would be. With the Atkins sleeves, port flow should be nice above the 3800 rpm mark.

As far as the alternator is concerned, I am quite aware a higher amp alt wont increase power. Don't take me to be ignorant, it just makes me think that you are just being a sarcastic ***. Not saying you are, that's just how you're coming off. The reason why I want the 130A alt, is because I have numerous power accessories that I want to run and a dead battery is not something I need on my agenda.

And as far as the S5 UIM to S4 LIM, I've only ever heard of people modifying them to work together. The only reason I dont want to go to an S5 lower is because I dont like the electrical activation of the 6PI system. Too much more wiring to have to deal with, and personally I hate most electrical work to begin with. The next problem is I am NOT willing to have to spend money to buy an S5 harness and ECU just to have make the 6PI be functional.

fidelity101

iTrader: (11)

4pt is always better than 6 pt. (except for rx8s)
and I would just remove the sleeves entirely. How often are you below 3500 rpm anyways?

lastphaseofthis

iTrader: (8)

as far as the rx-8 rotors go, have you built an n/a engine with rx-8 rotors to speak from experiance? Or are you just parroting what others have done wrong. rx-8 rotors will allow you to run more advanced timing, and therefor a potential of greater power, from proper tuning. i'm planning my own n/a setup for my FB, and i'll be sure to get it dyno'd and share. looking for a solid 190whp. and yes the stock fuel injectors *may * be adequate, but at 80 DC, they would put out enough for 220 at the fly. cutting it kinda close, and the fuel pump? i don't know if i would trust a turbo II fuel pump. more is always better, although the 3rd gen pump is kinda overkill, they're so cheap and available.

RotaryEvolution

iTrader: (30)

it's said because most scavenging is already maxed out with the 10:1 rotors without going to direct port injection. the 8 has an extremely complex intake system in order to get to the power level it's at.

the only real benefit of the rotors is light weight.

fidelity101

iTrader: (11)

+1

GSLSE-YA

about 5-6 years ago I tried a 6 port mild streetport with an aux bridge, and sidedraft style dual 50mm throttle body fuel injection. We never saw over 197whp. I don't think we had the ideal exhaust setup, but it will be difficult to get +200whp from a 6 port street port.

With that being said, there are guys running 6port streetports in SCCA EP that run around 225whp. That's in race trim with the best of everything. Power peak came over 9k rpm with a dual 51mm webber downdraft.

REAmemiya_fan

Damn, oh well. 200 whp is looking to be difficult on a street build, so hopefully something close will be doable. Also, lowering the rotating mass should equal a few more ponies to the wheels as well. Lightened flywheel, aluminum driveshaft, lighter wheels, etc. I know it won't open up 10+ hp to the wheels, but anything is better than nothing. Also, lightening the assembly should increase throttle response, which for me is a huge deal. I would much rather have a car that is light on it's feet and can respond to my every movement than something that I need to go into a corner knowing that I will have to wait for that perfect moment to give it gas, wait for boost, and not lose the back end. At least not yet, I'm almost 19 with no racing experience outside of Gran Turismo (with a simulation rig), so I want to start out small and basic and work my way up. Which is the whole point of this NA build, compared to starting off with a turbo and not honing my driving skills first.

AS for all the feedback, thanks a lot guys. Every little bit really helps out, and I learn a lot. Which is the point of a forum, right? Anyways, I will continue to find ways to make the engine a fun, fast, streetable NA.

How much do the turbo exhaust sleeves run on average?

REAmemiya_fan

Seeing as this is my DD, 3500 rpm isn't something I drive down the street at. Maybe I get to ~4k before shifting, and the occasional WOT to 7k, but suffering the torque loss below the 3.5k mark is not something I would want to do. Besides, with the Atkins sleeves, you have a smooth transition and flow of air, as compared to the air hitting a brick wall and being sucked into the engine. I know that's how it is stock to begin with, but again comes back that torque factor...

GSLSE-YA

It will be a good build and a fun car. I was just trying to give you some known HP figures with 6 port irons.

Many guys are against aux bridgeports, but you could consider doing a streetport on the primary and secondaries, and bridgeport the aux ports. You won't lose your low end if you keep the aux sleeves operational (since they will be closed below 4k anyway). Just a thought.

Cheers

j9fd3s

iTrader: (3)

exhaust gasses are hot, and want to be expanding, so they have more energy. the intake gasses just have maybe some momentum. so they intake is always bigger than the exhaust. that being said one way to pick up some power is with the headers, the RB headers have a really poor match to the port, and depending on the ports/and intake manifold are probably the wrong length too.

the injectors are easy, just get the stock ones cleaned. or update to the newer EV14 style. the injector size is fine. the fuel pump is ok too.

the big problem with the 6 port system is that the ports are too big, and they close too late. opening them earlier via porting will help power, but adds overlap which hurts part throttle low rpm. at some point there is a trade off. Mazda tried to make as little overlap as they could while making the ports big enough to keep high end power.

the S4 and S5 lower to upper bolt pattern is only different by one stud, so if you're willing to remove the stud (its the rear most one) they interchange.

i've got 2 Rx7's right now, a stock vert, and a 1st gen with a PP 12A. the vert is a lot of fun on the street, i like a power band that gets bigger as you rev it, which is what happens. its a little soft under 3k, but it wakes up after that, and peaks around 7k.

the PP (with the stock 12A air cleaner) acts very similar, but its got WAY more low end (intake opens earlier, closes the same as the 6pi), i could tow with it. PP vs FC, the p port just flat out runs away from an FC even though the air cleaner+mufflers keep it under 6500rpm. however on the street, its LOUD, and part throttle cruising is tricky, and it adds up to it not being that fun on the street unless you can let it run.

RotaryEvolution

iTrader: (30)

170-180 is a reasonable goal, 190-200 is going to be tough to accomplish without tuned headers and modified intake setup, racing beat won't cut it in that respect. i have nothing against them but their exhaust is rather roughly tuned and a basic design. iirc one of my customers noticed best results from his mindtrain header setup which picked up just over 10 horsepower i believe and sits now around 170WHP with the stock intake setup with mindtrain headers, unported motor with turbo exhaust sleeves.

GSLSE-YA

I agree with the need for better exhaust. I picked up 20whp when I changed from a RB setup to a better exhaust system. If you want to get close to 200whp your going to need a better exhaust which means more $$.

REAmemiya_fan

Whats better than the RB that isn't custom? Most likely i will be going with the RB set up though just because my dad is planning on getting me the streetable head and presilencer for Christmas. Im glad i still get to ask for presents haha

peejay

RX-8 rotors seem to not allow enough in-chamber airflow.

One of the highest power engines I've heard of used Turbo rotors. Interesting, isn't that?

Most people who have tried it agree that there is no power gain with RX-8 rotors compared to FC N/A. Higher compression does allow a higher torque curve but they don't seem to make as much ultimate power.

As far as ignition advance... the better the engine is, the LESS timing it will want for best power. Firing the ignition before top dead center means the engine has to compress an expanding mixture, and the earlier you have to light the fire, the more "negative work" you have. Requiring a lot of advance just indicates inefficient combustion. Don't get me wrong, you do need to run whatever advance the engine wants, but an engine that wants less advance will be an overall better engine.

jorx7

iTrader: (11)

all this is good, add the atkins sleeves they are proven to add 8hp, it makes the air ride smooth into the motor, rather than hit the wall then go in. turbo sleeves also. standalone apexi pfc with banzi adaptor kit, use the stock map sensor since your not running boost.

i ran my s5 n/a 6port.with all ports sleeves removed, vdi wide open, full racing beat full exhaust. no emissions,no ac, stock main crank pulley,duall alternator pulley, stock 460cc injectors. with apexi pfc,banzi kit, put down 190 to the wheels.

look up my name and youll see my t2 n/a fullbridge build i did, put down 245 with this new motor