[ska///235i]

here's Steve Dinan's story from Dinan's site, in his very first setnence of this long article...it talks about the "Hydrocarbon Absorber" removal (aka cardon filter)



DISPELLING PERFORMANCE SOFTWARE MYTHS
By Steve Dinan

BMW enthusiasts may have noticed that Dinan Performance Software released
for sale in recent years has been developed in combination with a replacement
high-flow air filter element and or removal of the Air Filter, Hydrocarbon
Absorber. The reason for this approach is actually quite simple: the revised
software calibrations in combination with the additional air-flow provided by a
superior flowing filter or air box provides greater gains, and therefore represents
an even better performance value. Naturally Dinan software continues to offer
additional performance benefits beyond just horsepower and torque gains, such
as a higher rev-limit, no top speed governor and improved throttle response. Of
course Dinan software is installed as it was meant to be, directly through the
factory OBD II connector, no trivial accomplishment from an R&D standpoint but
clearly the most elegant approach. Communication with BMW ECUs has
become very challenging, explaining why you see almost every other software
tuner requiring you to send your ECU to them for bench-programming instead of
being able to load it through the OBD II connector. (no “down time” for the car
itself).

Engine management systems have gotten so sophisticated and the knock-control
systems so effective that the power gains achievable from software alone are
often relatively small with modern BMW models. Basically, the engines are tuned
by the factory to produce nearly optimum power based upon the fuel being used
and other factors, leaving less power “on the table” for tuners to extract. Having
said this, we’re seeing some pretty “optimistic” or perhaps more accurately
“exaggerated” power gain claims in the market. As an example, I’ve seen as
much as a 25-hp gain claimed on the new M5 from software tuning alone! While
our research has clearly indicated that there isn’t that much power to be made,
we have purchased our competitors’ software and evaluated it on the dyno,
employing time-tested procedures and state of the art equipment. We have yet
to measure anywhere near the claimed power gains and in fact we are typically
seeing about half of what is being published, even with the removal of the
Hydrocarbon Absorber.

Our competitors often claim that Dinan is “backing off” on potential power gains
for emissions or warranty reasons, or even because BMW is influencing how
aggressive Dinan can be. Nothing could be further from the truth; we’re simply
providing the BMW enthusiast with scientifically valid dyno results. I’m more than
a little proud to say with confidence that we have the largest R&D department of
any BMW aftermarket tuner in the US, state of the art equipment, years of
knowledge and experience. We’re providing the BMW owner with every bit of
power possible from engine management tuning and certainly not “backing off”
for any reason. Our published horsepower and torque gains represent real,
measurable gains, based upon SAE standard J1349.

We will often recommend a high flow air filter. In the case of the M5, no filter
replacement is suggested because our tests revealed no measurable increase in
power over the stock filter. However, the removal of the Hydrocarbon Absorbers,
which have been demonstrated to restrict air-flow, does enable the Dinan
software to be more effective, much like a replacement air filter would for other
models. In both cases more air is flowing, and the Dinan software is tuned for it,
maximizing power output.
We’ve talked a bit about software tuning, along with some extra air-flow from less
restrictive filters. A logical question, then would be what about specific software
tuning for other modifications that might be applied to the cars. Modern BMW
engines are so sensitive to accurate tuning and setting faults that in almost every
case a specific version of software designed for use with an engine modification
will result in not only greater power gains but reduced potential for malfunctions
as well. The more extensive the modifications, the more important specific
software for those modifications becomes. I’ve had customers tell me that there
is no point in tuning a new BMW because there is no power to be gained due to
the fact that the cars are tuned so well from the factory. Fortunately for
enthusiasts, this has not been our experience at all. With the possible exception
of software, we are seeing substantial gains, as large or even larger in some
areas than we have realized from older BMW models. Having said that, the high
performance products themselves require far greater investment in research,
testing and refinement. As you might imagine, it is far more expensive to develop
and produce premium quality performance products today than it has ever been.
If you spend the necessary time to research the vehicle’s inherent weaknesses
and effectively address them, the power gains can be very significant. Using the
M5 as an example once again, the intake system we are developing for the V-10
is producing an additional 20-25 hp with matching software tuning. This will
represent one of the largest power gains we have achieved with this type of
product to date.

In addition to conventional power-tuning such as calibration of fuel mixture,
ignition timing, cam timing and torque limiters, Dinan software offers additional
value as discussed earlier. Removal of the top speed governor enables the driver
to achieve the vehicle’s natural top speed (under the proper conditions, of
course). The increased rev-limit improves acceleration times and allows for
optimized shift points. Drive by Wire programming improves throttle response,
making the car more responsive. In addition, when the car is modified with other
performance products, Dinan software is tuned for sensor transfer function and
fault diagnostic functions, reducing the potential of check engine lights and
ensuring BMW-like drivability. The new BMW control units are very sophisticated
and time consuming to understand properly but the results of these efforts are
well worth the investment.

Earlier in this discussion I mentioned the challenge presented by communication
issues with the modern ECUs. Dinan has successfully worked through these
communication issues with most BMW models and we can now load software
through the OBD II connector on the new (E60) M5, 550, 545, and (E63/64) M6,
645, 650, as well as the X5 and all of the 6 cylinder 3.0 and 2.5 liter engines
found in the 330, Z4, X3, X5, and 5 series from March 2003 through 2005.
That is not to say that future models won’t need to be sent to Dinan for
programming on the bench but our engineers are hard at work to avoid this
approach, at the very least minimizing the number of ECUs that need to be
handled in this manner.

As you can imagine, these challenges and complications have caused software
to take longer to get to market along with a sharp increase in the cost of software
development and the resulting retail prices in recent years. I have seen prices
from $1,500 to $3,000 for (E60) M5 software! Very high indeed, especially if you
factor in a realistic power gain claim. However, considering the cost of
developing software for the new cars and how important it is to a properly
running performance modified BMW, it doesn’t seem like enough! Dinan has
invested literally millions of dollars in recent years on software development and
while it was once a significant profit center for us, we now actually lose money on
this part of our business when you factor in the exorbitant R&D costs.
Regardless, we feel software is very important and absolutely necessary in order
for us to bring you the best running, most reliable performance products possible,
and at a reasonable price. Even with our matching 4 year/50,000 mile warranty,
the absolute best guarantee in the business, and the solid engineering behind
the product, Dinan’s M5 software is the least expensive currently available.

In the future, things will only become more complex and therefore more
challenging from an R & D standpoint. The software will take longer to develop, it
will cost more and the reality is that it will likely produce smaller power gains. At
the same time, software tuning will become even more important when modifying
your car with performance hardware! The one notable exception to this is cars
equipped from the factory with turbo systems. Since the turbo boost control is
accomplished with software, relatively large power gains can be achieved with
software alone. With proper software tuning, the boost can be increased on the
335, for example, to produce an honest 40-50 hp gain. It should be noted that
there is significantly less exaggeration by tuners producing software for
turbocharged cars because the gains are significant.

“Piggy-back” control units will also become more popular as access to the ECUs
and the software inside becomes more difficult. The naturally aspirated engines
will produce more modest power gains, just as with software. However, with
turbos in particular, significant gains can be achieved with piggy-back control
units. Having said that, piggy-back units simply cannot make as much power as
properly tuned software, regardless of the claims being made by companies
selling control units for the 335. Additional important features such as rev-limit
increases and speed governor removal are very difficult and usually not offered
with a piggy-back control unit. More faults and frankly compromised reliability will
also result from these control units when compared to good software. This is
because it is more difficult to obtain correct sensor, fuel mixtures and ignition
timing values without getting a fault. In addition, computer controlled turbos have
safety features that lower boost and re-tune the mixture and timing based on
heat exchanger efficiency, engine temperature and detonation. Often piggy-back
control units will compromise these safety programs because they “fight” these
corrections rather than implement them as would be the case with properly
engineered software.

At the risk of being blunt, it is important to realize that not all software available
out there is calibrated correctly. When we looked at some of the M5 software on
the market for example, we found a significant number of calibration errors. Sure
it takes longer to develop a well-engineered and thoroughly tested product. In
addition, the method by which the software is installed is also an important and
challenging aspect. While it has certainly taken us longer to get our software to
market than some of our competitors, our product improves the performance of
the M5 in many ways, including additional horsepower and torque, and it can be
installed at your local Authorized Dinan Dealer, eliminating the need for owners
to remove their ECU in order to send it somewhere for modification, creating
days of downtime. Clearly the Dinan approach is far more convenient.

Additionally, Dinan’s software is backed by the best warranty available anywhere,
matching the new car warranty coverage for up to 4 years/50,000 miles. No one
offers such a comprehensive warranty on their product, let alone coverage for
any possible “consequential damages”. I invite you to inquire about the details of
other tuners’ warranty on their software and/or piggy-back units.
If you have any questions about Dinan software you are invited to contact a
Dinan Performance Specialist at 1-800-341-5480.