I've read some debates on other forums that intake mods by themselves may not have reliable/reproducible performance benefits because of how modern ECU's work? Thet state that if you change intake to improve airflow etc., the ECU will eventually update it's fuel maps and somewhat negate the mod....is there anything to this?

 

The ECU will detune to keep emissions at the stock level. The way around this is to disconnect the battery every so often to clear the memory. It takes the ECU around 200 miles to detune completely to the stock level of emissions. If you don't mind disconnecting the battery and resetting the clock this is a simple solution. this is my understanding

 

There are parameters that the ECU works within. So far, it seems that the additional air brought in by the intakes hasn't exceeded those. The power gains are still evident on the dyno with a car that has 1,000 miles on the filter without disconnecting the battery.

Hope that helps.

Randy
randy@mini-motorsport.com

 

>>The ECU will detune to keep emissions at the stock level. The way around this is to disconnect the battery every so often to clear the memory. It takes the ECU around 200 miles to detune completely to the stock level of emissions. If you don't mind disconnecting the battery and resetting the clock this is a simple solution. this is my understanding

It's not that simple. The ECU will still keep the updates even without the battery. Resetting the ECU is a much much more complex process with the latest chips (like we have in the MINI).

 

So where is the ECU doing it's sampling of the emissions?? Is it's input for that data from the O2 sensor, or what?

 

"Fuel Fuel Fuel Fuel Fuel Fuel"
First off, with any newer ECU in virtually any car, under cruise situations and light acceleration, the ECU is always adjusting fuel for emissions reasons. The ECU stores this as a "long term fuel trim" and uses a "short term fuel trim" for the day to day changes in temp and AP. When the ECU is reset these trims go away and the car will relearn them over a period of time. This all goes away under full trottle.
Under full throttle, the ECU has a fixed map for fuel. So the trims will not effect this at all, nor will the ECU reset. The ECU has a fixed map for a couple of reasons.
One, for saftey reasons so the car won't run to lean and blow the motor up. Two, because the cars O2 sensor can't read anything accurately except for 14.7-1 AF ratio. The first O2 sensor(narrow band) in the car is there just for the short term and long term fuel trims, not for tunning under full trottle. If the car had a wide band O2 sensor,(more cars are starting to come with these) tunning under full throttle might be something the ECU would do.

"Timing Timing Timing Timing Timing"
Some of the same things apply with the timing side of the ECU, but some are different. Car has a base timing map, and the same sort of "timing trim" that is always being applied. The timing trim is a positive or negative number of degrees from the base timing map. When the ECU is reset, the ECU will start to advance timging untill it hears knock and then will back it off a couple of degrees. Under full throttle is where this is different. The ECU is always learning the timing curve under full throttle, as apposed to the fuel curve. Other factors that will advance or retard timing are the intake temp, and boost.
The higher the intake temp, the more the ECU will retard timing, and with more boost the ECU will also retard timing. All of these amounts of retard, are variables and that is one of the things an ECU reflash changes.
So if you install a pulley and gain X amount of HP, since the ECU retards timing with boost, there won't be such a huge gain until you have an ECU reflash.
So, reseting the ECU or diconnecting the battery wont have much effect on the full throttle power. With newer cars this is not trick to gain a few extra HP.

Hope that answers the original question about the ECU reflash, and about the emissions stuff.

Jeff Perrin
Alta Performance

 

Ok, if this is an issue why is Randy not seeing a change even after a 1000 miles. Perhaps it not to worry about.

There are lots of you guys out there that have seen the benefits of the intake or intake and exhaust, have you seen or felt a decline in your performance?

 

Ok, if this is an issue why is Randy not seeing a change even after a 1000 miles. Perhaps it not to worry about.

Could be the placebo effect.....tuners are in business to sell products which is ok but wondered why there is never any objective proven performance results on many claims like an extra 15hp for an exhaust or 12hp gain for intake, etc....where's the research other than the seat of the pants if feels quicker...

 

miniblues,

I totally agree with you.

I will confirm the findings on the dyno within the next week or so.

I am being very honest when I tell you that it definitely still makes a big difference, as I drive stock Ss fairly frequently. I think anyone else that can compare both stock and intake equipped cars will tell you the same thing.

I would hate to be seen as a company that just pushes product, as I would like to remain as the voice of objective evaluation. Each system out there has its merits and drawbacks. I have spent a great deal of time and money trying to determine what those are, and be able to make recommendations based on what a particular person may want out of a system. I have absolutely no quams in telling you if something doesn't really matter - ie stainless steel brake lines, different spark plugs, etc. The MINI comes with some good components, but as with all mass produced cars, some compromises are made. That could be for sound, or cost, or production issues, but they can be exploited by the aftermarket nonetheless. The intake and the exhaust systems are optimizations that make the car a little louder (or even a lot louder in the case of the Magnaflow), but make a BIG difference in performance. This has been verified on several different dynos - with most combinations of intake-exhaust producing between 12-18 horsepower at the wheels. I've also done exstensive testing on the track with four different cars on the same day in four different states of tune, and there is a big split between the cars with intakes and exhausts (all of which had had the intakes and exhausts for more than 1,000 miles) and the cars without.

The track testing continues, and I plan to continue updating information based on what the research shows. That includes subjective street driving, objective track times, and objective dyno testing - conducted by myself and others out there who are not manufacturers or suppliers.

I hope that answers some questions about where I stand. I've actually taken some flak for being as blunt as I have been in regard to what works out there, so I can guarantee that if I was just in it to sell as much as possible, I would have already been a little more tactful up until now. I am a hot rodder, and want to get the best products out there to the people who want them, period.

Let me know if you have any questions, or input on how to make what I do a better resource for MINI owners.

Randy
720-841-1002
randy@mini-motorsport.com

 

>>Could be the placebo effect.....tuners are in business to sell products which is ok but wondered why there is never any objective proven performance results on many claims like an extra 15hp for an exhaust or 12hp gain for intake, etc....where's the research other than the seat of the pants if feels quicker...

Well, thats not entirely correct. There have been those that have put the car on the dyno, before and after, i.e. Brian (Garfield) with his Supertrapp exhaust .

I can tell you that the effect that my butt feels is more than subtle. It is very noticeable. But those that are dynoing the vehicles have never indicated that things are normalizing over time. That could be because they haven't dynoed later, but I am willing to bet that when guys are Autocrossing and the 10-20 hp they gained improved their times, they would would see the loss in their times, and would have said something.

 

I've never heard of an ECU negating power increase from intakes or exhaust on any car. If anything it's the opposite. It takes some time for the ECU to "learn" that it has better airflow to work with and power should increase over the first hundred miles or so, then level off from there. If you're trying to decide whether to do ECU reprogramming or intake, I say go for the intake (search keyword madness). Mostly because the HP/$ is much higher. All the ECU reprogramming services for the MCS I've seen are over $700, pretty steep for the power you get. For reference, ECU reprogramming for my VW was only $350.

 

Let me know if you have any questions, or input on how to make what I do a better resource for MINI owners.

Thanks Randy...I'll look forward to reading your research findings and it is certainly refreshing to hearing about what works and what is not worth the $$