ArmAnirx7

iTrader: (24)

Details:
S5 Na
All stock
130k original engine (not rebuilt)

Mods:
dual Racing beach road race exhaust
coilovers (irrelevant to this situation but still thought I might list it)

Questions:
Is rtek right for me?

If so, What stage?

What is the maximum benefit for me?

Finally, what other mods can I make to upgrade to a higher stage rtek so that I can improve performance?

ArmAnirx7

iTrader: (24)

dual Racing beach road race exhaust... lol.. correction Racing Beat

GREAZERLOU

iTrader: (2)

Whats up man,
If your gonna stick with the stock intake manifolds (imo the best NA manifolds the factory ever made) and nothing bigger than a street port, then without a doubt get an RTEK. Its simple because all you do is send them your stock ecu and they rechip it to make your fuel/timing adjustable (among other cool things like being able to adjusting your VDI & 6PI points). All you need is an inexpensive Palm PDA and a wideband O2 sensor to tune it. On top of that, they send your ecu back with the stock fuel/timing settings so you can just plug it back in and drive it around like before and start the tuning process at your convinience. It doesnt get any easier than that, and really the only limitations of something like this is the airflow capacity of the stock manifolds because theyre sized for a broad powerband and have the 6PI & VDI features which help with power low in the rpm range. So for a street/weekend autocrossing scenario, this is hard to beat. Plus an optimal exhaust system for a motor like this is still on the quiet side. Now, if you dont mind a louder exhaust and a reduction in power down low to get the most out of your motor in the midrange/top end, like for a fast street car/weekend drag racer or road racer, then read on my friend.

If you think you might eventually go with a ported motor and an IDA/IDF Weber style intake with ITBs (the ultimate NA or NA + Nitrous setup imo) then definitely get an aftermarket standalone EFI setup. EFI + ITBs on an aftermarket intake manifold will get the most out of your motor for sure. Something like this is pricier and harder to set up and tune but if you see it through, youll definitely be happy.

Really it depends on what your long term performance goals are and how your going to actually use your car. Im actually looking for an NA S5 to set up with an RB Road Race header & presilencer, Dynomax Superturbos, MSD Ignition, Pineapple Racing 6PI Sleeves and a K&N filter, with an RTEK in control of the whole thing.

So thats my $.02, good luck with your ride man!!!

ArmAnirx7

iTrader: (24)

Thank you for your input sir.

I am assuming you are going to get the rtek 2.0 for your car correct? I see they make the 1.0 and the 2.0 for the Na.

I was thinking of doing the Pineapple sleeves as well. I hope it is alright if I contact you in the future if I have any questions about my set up.

GREAZERLOU

iTrader: (2)

no doubt! And yes, im referring to the stage 2 setup. I actually recently discovered the RTEK upgrade myself. My fast rotaries were from back in the day (late 90s/early 2000s) when most guys were running carburated motors. I had a few mild rotaries after that and then life kinda happened and I couldnt really afford it anymore so I dropped off the scene for a long time.

I just recently got rebit by the rotary bug and ive been on this board checking out what everyone has been doing lately and im glad to see that tuned EFI rotaries are so popular.

Before coming across the RTEK, I was originally gonna go with a "fuel only" SDS EFI controlling a set of ITBs over a street ported Turbo 2 motor with a high compression NA S5 rotating assembly. Ive since reconsidered that plan and am now gathering parts to do a mild tune an NA S5 RX7. Exhaust, K&N filter in the stock airbox, Pineapple Racing 6PI Sleeves and an MSD ignition with an RTEK optimizing the combo.

While im sourcing my parts as well as looking for a good, reliable car to use as my platform, im taking the opportunity to learn as much as I can about tuning the RTEK so by the time I find a car and do my upgrades, ill have an idea of what im doing tuning wise.

Anywho, if you decide to go that route, RXCookies has a thread in the RTEK section of this forum where he, I and a few other guys are all building similarly set up RTEK'd NA S5 RX7s. Were all in the "build stages" right now so there wont be much tuning info for a while, but the idea is for all of us to pool our findings as we learn and share tips, dos and donts, questions, mistakes weve made along the way, fuel/timing maps, etc as we all progress through our builds.

Heres the link if you also decide to go our route and wanna join in on the debauchery. Either way, good luck!

https://www.rx7club.com/rtek-forum-168/s5-na-rtek-2-0-tunning-maping-964121/

ArmAnirx7

iTrader: (24)

Thanks for the link. I just subscribed to the thread

j9fd3s

iTrader: (3)

we ran something like that road racing in NASA's PS1 class. its a pretty simple combo, the exhaust does a lot, and then you just tweak the fuel and timing. adding 4.88's or short tires also makes a HUGE difference.

if the engine is nice an tight you can expect 165-170rwhp, with a broad power peak in the 6500-7200 area.

lastphaseofthis

iTrader: (8)

i would use an Rtek to control an N/a 13b all the way up to a peri port. even when using aftermarket intakes and itbs, you can still use the rtek, and just adapt the stock TPS( or just have the narrow band TPS, if premixing)

with the S5's you get 2 rpm controllable switches built in. you could use one of those to open up a late bufferly valve on the peri's.

point is, get the rtek 2.1, it can go with you a long long way.

ArmAnirx7

iTrader: (24)

Let's say I don't add anything else to my car. How would rtek 1.0 benefit me? Would it just be a plug and play or would I still need to change setting with a palm?

GREAZERLOU

iTrader: (2)

J9FD3S
Thanks for the info. 165 or so to the wheels is fine for a daily for me. This is gonna be my only car so broad powerband, Heat & A/C, simple suspension setup, etc are all part of the mix. Then when rebuild time comes there will be a swap to T2 rotor housings to get rid of those exhaust splitters along with a mild street port and one final retune on a dyno an thats pretty much it for that car.

LASTPHASEOFTHIS
Ya ITBs on a ported 4-Port with an NOS setup in a bare bones RX2/3 is my all time favorite combo. Red or Blue steels with polished rotor housings... ahhh the good 'ol days! Maybe one day.

ArmAniRX7
The Stage 1 doesnt allow tunability of your fuel/timing and therefore, imo wouldnt be worth it for me. The only thing the Stage 1.0 does for an NA S5 is give you the ability to switch the oil metering device out for an S4 model which they say is more reliable (i didnt have a problem with it on my last NA S5). Its inexpensive and you can change the chip yourself but I wouldnt go that route on my car. I put Digital Tunings website link (the maker of the RTEK system) down below so you can check it out and get answers directly from the horses mouth. Good Luck!

http://www.digitaltuning.com/index.php?pid=rtek7

j9fd3s

iTrader: (3)

it'll be a fun car. the Rtek really fattens up the power curve compared to the stock ECU, so you don't gain a ton @peak, but you gain like 10-12lbs-ft between 4000-6000.

BettsySlevin

iTrader: (3)

Hey guys kind of off topic but does anyone know where I can find info on na >forced induction I'm thinking of going this route. Ive been through the single turbo setup section and was reading through this one, and was hoping if perhaps someone could point me to the correct secton

Thanks for the help in advanced

ArmAnirx7

iTrader: (24)

Are you going to run a wideband o2?

GREAZERLOU

iTrader: (2)

J9FD3S
Yep, thats exactly what im after my man...

ArmAnirx7
Yep, thats what youll use to actually make your tuning changes.

The stock, narrow band O2 sensor is used by the ecu when the car is under light load (ie light throttle/cruise conditions) to keep the air/fuel ratio around 14.7:1 (aka stoichiometric) which gives you the best fuel economy/emissions. The nature of narrow band O2 sensors is that they dont*tell the ecu what the actual air/fuel ratio is. Instead, because of its limited capabilities, it can only tell the ecu whether the mixture is rich (lower than 14.7:1), stoichiometric (14.7:1), or lean (higher than 14.7:1) but not by how much. So the ecu basically just chases a stoichiometric signal. This is whats referred to as closed loop operation and is still retained after the RTEK upgrade.

All that is fine for light throttle/cruise conditions, fuel economy, emissions, etc. but not for high load conditions, like when you stomp on the go pedal. In this situation, the ecu switches over to open loop operation and instead of using the O2 sensor for controlling the air/fuel ratio, it uses preprogrammed fuel/timing settings (aka "maps") that the factory put into the ecu to produce the most horsepower at the expense of fuel efficiency. This is where the wide band O2 sensor, palm PDA & RTEK upgrade come into play.

The RTEK upgrade gives us the ability to get into those stock maps and make adjustments to get the most out of the motor. Even on a stock motor theres room for improvement (see RTEKS website for more info on that) and it becomes even more valuable once you start upgrading your exhaust, intake, ignition, etc.

Now, to make use of that adjustability you need an O2 sensor that instead of giving a simple rich/stoich/lean signal, will tell you exactly what the air/fuel ratio is so you know how much of an adjustment to make to the stock fuel/timing maps and thats exactly what a wide band O2 sensor does. So basically, youll end up running two O2 sensors. The narrow band O2 will be in control during closed loop conditions as usual and the wide band O2 will be there as a tuning implement, constantly telling you what your air/fuel ratios are so you can make your fuel/timing changes with the PDA. Two different O2s, two different purposes.

So now that you can accurately read your air/fuel ratios and have the capability to adjust them, you need some sort of way to view all of this information which is where the PDA comes into all this. With the PDA you can make graphs of what your motor is doing so you can analyze/make/load your changes into your ecu. And thats pretty much all there is to it, other than doing the actual tuning which is what im reading up on these days. But as long as your careful and make only small changes at a time and save your previous maps so you can go back one step if your get into trouble, it should be ok. Now if you really get things outta whack, the PDA can reset the ecu back to stock so you can regroup and try again.

Features like this are expensive and only used to be available with a standalone system like a TEC, MoTec, Haltec, DFI, etc. which also required you to install their ecu, rewire your car with their wiring harness & sensors and buy a compatible laptop which by the time your done, would put the price way up there. Plus having your car off the road while you did all this and then going through the process of creating/programming your base maps from scratch is a major commitment. Then if you have to pay a tuner to do all this for you its that much more expensive. Definitely worth every penny however if your building a higher horsepower motor/dedicated track car thats constantly evolving amd always has to be making top horsepower. But for a street motor making modest power levels id say its overkill to go that far.

Thats what I like about the RTEK. You can have all those capabilites, retain your stock ecu/wiring harness/sensors, dont have to program it from scratch and all you have to do is send them your ecu (or a spare so you have zero down time), buy a Palm PDA (under $200) and get a wideband O2 sensor & gauge (which you need if your going to do any kind of tuning anyway) and thats it.

Awesome bang for the buck imo

ArmAnirx7

iTrader: (24)

Thank you for all of this info...It is great to have someone like you on the forum

GREAZERLOU

iTrader: (2)

Nooo problem. The rotary world is too small for us not to help each other out... good luck!!!

ArmAnirx7

iTrader: (24)

I am trying to gather all the components to set up the rtek so here are my questions..

1. I found a wideband but it has a 0-4v output.. i was reading the rtek instructions and it said 0-5v.. would the 0-4v work? What is the difference?

2. For the wideband.. do i need a controller if I going to get the rtek?

thanks

lastphaseofthis

iTrader: (8)

theres a thread called widebands what you think you know, and what you don't. find it and read it. rtek 1 is pointless, for the most part... rtek2.1 or go haltech.

ArmAnirx7

iTrader: (24)

thanks .. I will look for a wideband "system" which must have a 0-5v output!

GREAZERLOU

iTrader: (2)

Whats up Armani - any progress on your ride? I finally just picked up my S5. It needs a lot of cosmetic work/little stuff but its got a rebuilt motor that feels good and runs real nice. So far ive only been able to set up my exhaust (road race header, road race presilencer, twin 2.25" piping to a single 2.5" Magnaflow) - now I just gotta get all the little stuff sorted out before I can start upgrading. Anywho, hope all is going well with your ride man!!!

Pettersen

iTrader: (1)

Remember that the rtek doesn't allow you to remove the MAF, wich IMO makes it a bad choice for an eventual itb setup.