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Discussion Starter #1
On Friday afternoon, I plan to install my CS SRI and TIP on my 2010 MS3. Obviously, the ECU will be reset, as the battery must be disconnected to complete the install. From those with expereince with this mod, approximately how long does it take the ECU to "learn" the new Air/Fuel Mix parameters? Should I expect rough driving for the first few days?
 

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Shouldn't be rough at all, but it does need some time to learn the new fuel trims etc before you go WOT.
Just give it 20 minutes or so of regular driving before doing your butt dynos...
 

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When you disconnect your battery, I like to turn the ignition on and leave the doors open to make sure and power is drained. You can start driving your car as you please and the ECU will learn your driving habits. Drive aggressively and the car will want to drive that way. Drive like a granny and thats what you will get.
 

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From a sticky somewhere else...

"Our car uses Short Term Fuel Trims (STFT) and Long Term Fuel Trims (LTFT) to adjust the AFRs to account for variations in the intake system. The reason this feature is in place is because when the ECU goes to decide how much fuel to add, it cannot trust its sensors 100%. When the ECU reads from the MAF sensor how much air has entered the system, it calculates how much fuel it needs to inject in order to achieve a commanded AFR...let's just say this is 14.7:1 at this moment. Well, what happens when it injects the amount it thinks it needs to inject, but then reads the wideband O2 sensor to find out that it came up lean and actually got a measured AFR of 15.5:1? Why was there this disparity? The answer is that sensors aren't perfect, and may be off by a bit. In order to account for this, the ECU uses what is known as a STFT to add/subtract an offset to the current amount of fuel that it's injecting to increase/decrease the measured AFR to match its commanded AFR. If the ECU keeps seeing a STFT of the same value, it saves this value into what's known as a LTFT. This LTFT is then applied to the commanded fuel injection amount to account for the inaccuracy of the sensors. After applying the LTFT, checks the wideband O2 sensor to see how close it got to its commanded AFR and decides if it still needs to add/subtract an additional STFT to achieve its commanded AFR. This allows the ECU to "learn" how this particular car works and apply fueling accurately. In a car that is operating normally, the ECU will take 20-50 miles (roughly...your mileage may vary) to learn the LTFTs that the car requires, and then run with nearly-zero STFTs most of the time. This, incidentally, is what is meant by allowing the ECU to "learn" after a reset.
There are four distinct LTFTs that I have seen our ECU to use. One or more of these may just happen to turn out to be the same, but they are usually different from what I've seen (since flow through the intake system changes under increasing flow conditions/turbo operations). These fuel trims cover:

1. Idle
2. Engine breaking
3. Light Throttle
4. Heavy Throttle (used for WOT operation)

These LTFTs are applied at these particular times in conjunction with STFTs (except at WOT...explained in a sec).

Now, you ask: why bother with LTFTs when you already have STFTs? Well, the reason for this is that LTFTs allow you to get things right the first time without having to react in order to correct a lean condition, fixing the problem before it happens! Equally important, LTFTs allow us to safely run in what's known as "Open Loop".

Our fuel system has two operation modes: "Open Loop" and "Closed Loop". These operation modes are used for different reasons...Closed Loop is basically an emissions/fuel conservation mode whose main goal is to maintain an AFR of 14.7:1, which lowers emissions and increases fuel economy...at the cost of raw power generation. In this mode, the ECU monitors its sensors very carefully and uses its STFTs and LTFTs to maintain 14.7:1 as closely as it can (with slight dips to protect the engine from damage as load varies, of course...but it always settles to 14:7). Closed Loop is usually accompanied with obscenely high spark advance (as high as 50+ degrees) and other assorted efficiency optimizations. This is the mode that we run in most of the time in our car...unless you go heavy on the gas pedal, of course, which causes the car to go into what is known as: Open Loop is a mode whose main goal is to safely achieve high power output while controlling engine cylinder temps and avoiding knock. At this point, the ECU ignores its O2 sensors and simply runs off of preloaded tables to decide what AFRs, timings, etc. that it will command in order to raise power output without regard for fuel consumption and emissions.

This is where LTFTs are absolutely imperative: The sensors are every bit as untrustworthy in Open Loop as they are in Closed Loop. How can the ECU reasonably expect its commanded AFRs to be properly achieved if it's not monitoring the O2 sensors? The answer is that it applies the LTFTs (without using STFTs afterwards) it learned while running at heavy throttle. The assumption is, of course, that heavy throttle flow and sensor characteristics mostly mirror the flow and sensor characteristics of WOT operation. This system usually works decently well and gives the ECU roughly the AFRs that it commanded. "
 

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Discussion Starter #6
ITS HERE!!! Now to get it installed!!!
 

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As you probably have already read - getting out the stock parts is by far the most time consuming - as far as rough driving is concerned - im going to say no, you shouldnt expect it to drive roughly

when i installed mine, i let it idle for a few minutes - drove about 10 miles, parked it, then drove to work (train station) the next morning, another 15 miles i think - i dont remember having any issues at all

if the ecu did NOT reset - i think is where you would likely run into issues, but if you diconnnect the battery before the install and reconect after - that should be more than enough time

the only thing that you might have to do is reset your am/fm/sirrius presets (if you have bluetooth hooked up the phone book remains however, so thats nice) - and the auto up/down button on the window - to do that just roll the window all the way up, then all the way down, and all the way back up again

the sound on the SRI is pretty sweet - didnt like it at first but i do now - good luck
 

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Discussion Starter #9
Ok, it is installed. I hooked everything up and ensured the connections were snug, then fired it up...no CEL. Then after driving 5 minutes and turning it on and off, I threw a CEL. This morning when i had more light, I looked under the hood and realized the boost solenoid had come loose. Snapped it back into place and reset the ECU. Fired up the MS3 and problem solved. So far I notice a huge difference in the audio on the turbo spooling, much more felt torque, better fuel economy, but I am unsure on any increase in acceleration??? It seems to be sucking a lot of air, casuing it to be a little slower off the line, but much smoother through the higher RPMs. Lastly, I noticed the plastic piece that appears to be connected to the radiator, no longer has anything connected to it??? Is that correct?
 

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Discussion Starter #10
I took it to the dealership, as it was due for a complimentary oil change. The mechanic confirmed that everything was installed correctly and they all gathered around to hear the sound. The mechanic said the extra plastic piece that is no longer attached can be removed. It is no longer needed. It was nice to get confirmation that I installed everything correctly.

The turbo spool at highway speed is AMAZING! I hit the gas hard about 10 yards behind a RX-8 with the windows down and the driver spun around to see what was coming!!!
 

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Ok, it is installed. I hooked everything up and ensured the connections were snug, then fired it up...no CEL. Then after driving 5 minutes and turning it on and off, I threw a CEL. This morning when i had more light, I looked under the hood and realized the boost solenoid had come loose. Snapped it back into place and reset the ECU. Fired up the MS3 and problem solved. So far I notice a huge difference in the audio on the turbo spooling, much more felt torque, better fuel economy, but I am unsure on any increase in acceleration??? It seems to be sucking a lot of air, casuing it to be a little slower off the line, but much smoother through the higher RPMs. Lastly, I noticed the plastic piece that appears to be connected to the radiator, no longer has anything connected to it??? Is that correct?
Yes, there shouldn't be anything connected to that piece. I would leave it in there since it brings some cool air in towards your new intake.

The intake does actually make you lose some power down low, but you get way more up top!

If you get a race pipe you will get all that low down power back and then some! For another $150 I would highly recommend you put in the race pipe next.
 

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I took it to the dealership, as it was due for a complimentary oil change. The mechanic confirmed that everything was installed correctly and they all gathered around to hear the sound. The mechanic said the extra plastic piece that is no longer attached can be removed. It is no longer needed. It was nice to get confirmation that I installed everything correctly.

The turbo spool at highway speed is AMAZING! I hit the gas hard about 10 yards behind a RX-8 with the windows down and the driver spun around to see what was coming!!!
Man, after reading that, I can't wait to get my parts in! I have a Corksport SRI and Racepipe on order and I am getting goosebumps reading your story about the RX-8 drivers response to your car.
 

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Discussion Starter #14
Yes, there shouldn't be anything connected to that piece. I would leave it in there since it brings some cool air in towards your new intake.

The intake does actually make you lose some power down low, but you get way more up top!

If you get a race pipe you will get all that low down power back and then some! For another $150 I would highly recommend you put in the race pipe next.
How difficult is the install? I need to regain my low end!
 

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Discussion Starter #16
You just order the one that will fit your stock exhaust, then unbolt the 4 bolts and take out the stock pipe and screw in the new one. Pretty easy. :walkman:
Thanks I was hoping it was that easy and wouldn't require any welding.
 
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