I personally like the S-AFC II. IT always works, easy to install and easy to sell once you are set to go to your next step. Personally if you want ultimate flexibility get an Apexi Power FC which replaces the stock ECU and allows full adjustment of ALL paramters as well as diagnostics. I don't see why anyone would use anything else on the larger setups.

 

Yes, because that's the first thing anyone does when trying to make their car faster... PULL TIMING.

You must follow the Shiv Vishnu school of backwards tuning.

 

Brilliant. FWIW, the Stage 0 car I dyno tested at Pruven put down 292 wheel hp today on their AWD dynojet. And yes, timing was pulled in certain places to control knock sensor activity. Same goes for the Stage 1 car that put down 306whp. Both on 93 octane gas.

Not massaging the timing curve and relying on fuel and boost control (a la S-AFC with MBC) only to maximize peak hp usually results in lumpy and inconsistent dyno pulls riddled with signs of spurious knock sensor activity. The hard part is not making a big peak number at 6500rpm. The hard part is maximizing hp at all engine speeds and being able to run it back to back within a 2-3whp variance with no more than a 60 second cooldown between runs.

My 2c,
Shiv

 

Wow, I'm genuinely impressed, Shiv. Please tell me that there's some way you could get Dan to actually drive the car down a track to get a 1/4-mile time for it too.

Let me rephrase my "backwards tuning" comment. A well-tuned 4g63 can run around 24 degrees of timing (just ask Hal). In my opinion it seems a little silly to pull timing when it's helping you make horsepower. But then again (also IMO), it's silly to try and accurately tune a car with a piggyback in the first place (which is why I would wait for the UTEC).

Shiv, what's the difference between stage 0 and stage 1, and why such a small hp difference between the two?

 

FWIW I'm starting to reevaluate my choice in fuel control.. I'm leaning towards a more complete solution, either a custom flash, an AEM-EMS If they ever release it.. or the UTEC.. Ultimately I'm spending way too much time tuning and battling the knock sensor causing the ECU to pull timing, plus fuel cut and inconsisten part throttle response..

Don't get me wrong.. The S-AFC is amazing for what it is.. It definitely allowed me to get my HP Way up.. But unfortunately the more I tuned it, and the more the weather would vary.. I spent more time adjusting the boost controller and Fuel settings to compensate for drivability issues that I'd come across.. A good example is part throttle full boost conditions that I hit once in a while.. Or the fact that even with the stock boost solenoid and an aftermarket exhaust you'll experience periodic boost spikes as high as 22psi.. Etc.. All of these things really need a more elaborate solution that compensates for more conditions than what we have available currently.

 

I agree with what Shiv says about the process of tuning with a piggy back device.

When you attenuate the maf signal in a evo 8 you cuase the car to think there is less load and it runs a line or two higher on the stock ign timing map. This results in greatly advanced timing. (One of the reaons why the piggy backs make good power on the evos)

The result is lots of detonation around the point of peak trq and while the car is on high boost - aggrivated when running higher boost than stock. A representative curve is here :

http://www.pruvenperformance.com/images/aldyno3.JPG

Then you can adjust the timing - retarding it in certain spots to avoid detonation which triggers factory knock adjustments and get a much smoother and wider power band like so :

http://www.pruvenperformance.com/images/aldyno4.JPG

To me this is a very primative and undesireable method of tuning.

A reflash offers much more advanced control of the tuning process and much better results. With this piggy backs there is no way to deal with partial load tune; and partial thotlle full boost becomes a real issue.

I am now able to write in the fuel map and it has no effect on the maf signal or timing what so ever. Also - the fuel curve is load based and I can alter all load sectors and optimize the fuel for all conditions.

Similarly, the ign curve needs only minor corrections and is load referenced.

Finally, I notice that the reflashed cars are smoother and more linear in the power band. I feel the piggy backs have a more choppy, rough feel on driveability. I theorize this is realted to inherant delays in the calculation of maf signal corrections or inaccurate calculations. My emanage data logs showed the machine was far less than ideal in calculating the revised maf signals from the stock inputs.

The reflash is better in every respect to a piggy back devise.

 

I agree, totally. Though I'd sooner leave the ECU stock and wait for the UTEC because I like having the tunability. I'm not saying reflashes suck or anything, because they are really great for what they are, just not for me. Piggybacks really do suck, which is why I think the price of the XEDE is a bit outrageous.

 

The UTEC is am amazing product, however its cost and learning curve make it not an ideal solution for everyone. not to mention its not even available yet

I see the ideal reflash customer as being one of the following:

1 - Someone with essentially a stock car who wants a quick easy cost effective 25 whp and wants to be able to get back to completely stock easily if needed.

2 - Someone who is planning a specific number of mods in one shot and gets it tuned to optimize those mods and then is content - eg an exhuast, inake and boost controller. Unlike some other reflash companies, I encourage clinets to get what ever they want and I'll tune your evo to maximize the mods you want.

3 - Someone is is going over the edge (like me) with mad mods and who wants the rev limit higher, fuel cut out and the base fuel and timing curve altered with a general direction but who will fine tune their car with the SAFC or other piggy back device, maybe even a utec! This user is looking for the rev limit and fuel cut mostly but also likes to havce the fuel and timing curve 90% on the money so the piggy back corrections are more limited. This user would also consider a stand alone but wants to keep stock like driveability and fucntion - EVEN if it means making a few less HP becuase they have to run a maf sensor.

Reflahes are not for everyone but they are a very cost effective and powerful tuning solution that works great for anyone who is planning to stay under 450 whp (over 450whp I recomend a total stand alone)

 

All of this UTEC talk... Personally, i am thinking of taking my chances with the Greddy Emanage linked to the E-01 for tuning purposes... I just found a dyno that could help with everything, so i am just going to need some time to get everything installed, i am doing some other mods first... But i would like to hear some comparison conversation to the

emanage - E-01 setup...

 

I have tuned many Rx-7's and I though it's about -1 timing per pound of boost with some fuel added. More boost = more fuel. Any rule of thumb for the evo?

 

I think I talked with you on the phone a while ago if you are in Atlanta. Right now I am getting the David B's turbo back and going to wait on the AEM. I tell you once the AEM comes out you are going to throw this AFC BBC CBS whatever in the trash. A stand alone is the way to go and it should be a lot better to tune and I am going to take the time and the money to learn to tune the base map the David will put out with it. Just wait if you can, if you are fisrt you always get the worst stuff. :-)

 

Also is this car Mass air or speed density? The reason I am asking is because Mass Air should be a piece of cake, you tell it 12:1 and let it use fuzzy logic and adjust. I know that several years ago when I was into doing tuning on the Rx-7 TT it was speed density and that sucked, at least for me. Because you would take a map at 70% tps and would have to set that to a RPM and then make fuel / timing / boost. Also with the AEM how may points does the map have? Like this sfac thing has 12, I have never seen one just taking a guess. Say it has 500-1000-1500rpm and so on. so if you put +5 at 500rpm and +12 at 1000rpm will 750 be about 8? The problem with this is what people are seeing, it getting lean with the boost spike and you will NEVER get it right because it will be pig rich somewhere and a little lean somewhere else.

 

If you follow the emanage forums you will see there have been many reports of burned out ignition coils with the emanage. Thats why i just use mine for fuel now and dont activate the ign timing fucntion

 

Stand alones are great for making max power. They don't idel as well as stock and they take many many hoursof careful tuning to dial in good driveability and feel. having already used several stand alones - NONE of them are as advanced as the stock systems. For casual upgraders who are looking at the 350 - whp to 400 whp range the reflahsed stock ecu will do the same job with a lot less hassels.

Of course after 450 whp the stock maf signal is maxed out and its time for a stand alone for sure !!!!!!!!

 

Saying a car can run 24 degrees of timing is like saying my car can drive at 80mph at Lagana Seca. Yes, big deal. But the real question is: under what conditions are you running 24 degrees. Is that the max number you see during a run? Or are you running 24 degrees everywhere under full boost? Or is it only reaching 24 BTDC just before redline?

EVOs don't run a lot of advance. This is fact. The factory EVO runs single digit advance numbers during a full-throttle dyno pull through most of the rpm band, only ramping up to 15 to 18 to 20odd degrees BTDC in the last 1500rpm before fuel cut. This is why we adjust timing with the XEDE in 0.25 deg increments. taking away one full degree of timing on a car that is only running, say 5 degrees of total timing is going to yeild a massive torque loss.

BTW, a slightly modified version of the XEDE does have the ability to run stand alone timing control like a AEM, Autronic, etc,. programmable ECU. During the initial mapping of the EVO, we did just this to see where the knock thresholds of a stock EVO were just to see how much power was truly on the table once knock sensing was taken out of the picture. The answer is, and was, none. In fact, if you listen with det cans while dyno testing a stock car, you will actual hear mild rattling just *before* the knock sensor intervenes and yanks back it's 2-3 degrees of timing. So, no, the knock sensor is not too sensitive. I'd be happy if I could ever find an aftermarket knock sensor to work as well as the factory system when it comes to distinguishing actual knock from general engine noise. The fact that the factory knock control systems is active until just before redline (and not inhibited above 6000rpm or so as in many other turbo cars) goes to show just how well the powertain folks at Mitsu did when programming knock control system logic.

The Stage One car made approx 15 more peak hp than the Stage Zero car. However, the Stage One car made more power earlier and held up more power later until redline. Just comparing peak numbers doesn't really tell you much about the difference in how the two cars drive. Also, there's a pretty big hp variance among stock EVOs so expect these variances to exist in modified EVOs as well. I wouldn't be surprised if the Stage Zero EVO picked up another 20-25whp when upgrading to the Stage One. Either way, I'm quite satisfied with the results on both the baseline maps as well as with custom tuning.

Your comments suggesting that tuning with piggy-backs is silly tells me that you have not had luck doing so. This is because the tools you have used have been inadequate. This is fact and I cannot change that. I have been tuning stand-alones, piggy-back and remapped ECUs since the early 90s and when programmed properly (with good tuning platforms), on just about any application, they all make the same power with their own sets of tradeoffs. This is not surprising considering the same portion of fuel, spark and boost (if applicable) will always make the same power (with the expection of some systems, which I won't mention here, that don't do a good job of charging factory coils). The differences between all three approaches falls down to individual shortcomings. Drivability, adaptability, user-tunability, upgradeability, ability to drive additional injectors, # of general purpose outputs, emissions related parameters, safety margins, etc,.

Just pick the one that best suits your needs and don't misinform others that there are inherent differences in actual power producing ability. There are not. The differences comes from tuners not being able to tune them all to the best of their individual abilities.

Just my 2c,
Shiv