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Good Morning, everyone. I just purchased a new Mazdaspeed6 off of the showroom floor on Saturday the 22nd and I couldn't be happier. This car is absolutely stunning and I love it. I had been looking at this car, the Pontiac GTO (which the wife ruled out for me because she hates the way it looks), the Audi A4 2.0T, and another truck (had a '99 Ram). I went with this one after careful consideration and lots of racking my brain. It just had more features and conveniences, and it was more affordable and practical than the others when it comes to gas mileage and getting my kids in and out of the back seats (difficult in the GTO). I still can't believe how well this thing accelerates for a 4 cylinder car. 15.6 psi of boost is fairly high, but man, can you feel it! And the car looks really nice, aggressive yet classy at the same time. I definitely made the right choice with this car.

Anyway, I just wanted to say "Hi" and introduce myself. I'm proud to be part of the Mazda family and I'm glad I found this forum. Lots of great info here.

I also found an article from 2005 on the JW Fisher website about the DISI engine. It references a 2001 article by Ford on the engine. It's a decent read, hope you find it interesting. It also may help explain why the DISI engine runs out of breath at higher RPMs:


From the JW Fisher website:

Direct Injection is already in use by several manufacturers around the world,
and it's one of those few technologies that actually delivers it all:
performance, drivability, gas mileage, and emissions. The technology can also
benefit 4-valve engines with a wide range of torque and top end power.

Unfortunately when it comes to Ford, this technology is in very limited use.
Long-term research has yielded a notable first step, one that hopefully shows
the future, in the 2006 MazdaSpeed6 (direct-injected 2.3 liter 4 cylinder,
variable intake cam timing, turbocharged and intercooled). This engine, with
little boost and a disadvantageous intercooler design (directly on top of the
engine to improve throttle response and crash survivability - but at the
expense of heat soak), easily makes out-sized HP and torque: 274-horsepower,
280 lb-ft of torque. The nozzle is near the intake valves. Note that the spark
plug is in the normal location and the rest of the cylinder head components are
also in their conventional positions.



DEARBORN, MICHIGAN, AUGUST 21, 2001 - Direct injection technology originally
developed for diesel engines has shown potential fuel economy improvements of
approximately 20 percent when adapted by Ford Motor Company engineers for
gasoline engines.

This technology - called DISI for direct injection spark ignition - is being
tested in a 1.1-liter three-cylinder gasoline engine that achieves 70 hp.

In primarily urban driving, this translates to a 21 percent improvement in
fuel economy from the engine technology alone. In mixed urban and highway
driving, the engine is expected to improve gas mileage by 10 to 15 percent.
Combining DISI with other new technologies that take advantage of its low-RPM
efficiency should produce even greater savings.

The engine is also expected to meet or exceed European Stage IV emissions
standards - that take effect in 2005.

How it Works

In a direct injection engine, the injection nozzle is located inside the
combustion chamber, rather than in the induction pipe as in multi-port or
throttle-body fuel injection.

With a conventional fuel injected engine, all cylinders are supplied with a
mist-like mixture of air and fuel, at a constant 14.7:1 ratio. One or more
injector nozzles spray fuel into the air stream being fed to the intake valves.
This spray is mixed with air during the intake stroke and flushed into the
cylinder, where it is ignited by the spark plug.

The throttle valve determines how much of the air-fuel mixture enters each
cylinder. A closed throttle valve means little air in the engine, and thus a
small amount of injected fuel, while an open throttle means a lot of air in
the engine, equating to a lot of fuel.

Under traditional technology, the air-fuel mixture inside the cylinder can’t
deviate very much from the optimum 14.7:1 ratio of air to fuel. In particular,
air-fuel mixtures that are too lean simply won’t ignite.

DISI engine technology uses so-called stratified charging to overcome this
limitation.

With DISI, the spark plug is surrounded by a relatively small, precisely shaped
volume of ignitable air-fuel mixture that results when fuel is sprayed toward
the spark plug just before ignition. Only the area directly around the spark
plug, at the top of the cylinder, contains air-fuel mixture. Other areas inside
the combustion chamber merely contain air or recirculated exhaust gas.

This stratification of the charge allows the new DISI engine to burn mixtures
with a much higher rate of air than conventional lean-mix engines. With the
Ford DISI engine, the fuel-air ratio can increase to 60 parts of air (instead
of 14.7) for every part of fuel.

The cushion of non-combustible gas around the combustion chamber also means
that less combustion heat has to be evacuated. This improves the thermal
efficiency of the engine.

Fuel is injected into the cylinder. The shaped piston crown guides the air/fuel
mix to the spark plug.

As the spark plug fires, igniting the mixture, surrounding areas contain only
air or recirculated gases, forming an insulating cushion at the cylinder walls
and cylinder head.

Another factor contributing to improved fuel economy is the ability to increase
the compression ratio from about 10:1, as is normal, to approximately 11.7:1
without the need for premium fuel, because direct injection reduces the
tendency of engine knock. The higher compression ratio alone increases
efficiency by about two percent.

The DISI charge stratification process works best at low and medium loads in
the lower half of the engine speed range, where traditional gasoline engines
are least efficient.

The major fuel reduction potential of 21 percent is realized in the urban
driving cycle because, under these driving conditions, the DISI engine operates
in a stratified-lean mode most of the time.

Synergistic Technology

Changes in the coolant system also could help to improve fuel economy for a
vehicle equipped with the DISI engine.

A typical feature of DI engine thermodynamics is the difference in thermal
losses, depending on whether the engine is operated in the economy or full-load
mode. In the economy mode, an insulating blanket of air and recirculated
exhaust gas helps keep heat away from the cylinder walls and head. In the
high-powered mode, more heat is released.

A new control system for the coolant circuit could shut off the fan motor over
a longer period of time or reduce the operating speed of the water pump, during
economy mode operation. Either would reduce operating drag on the engine, and
improve economy.
 

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Discussion Starter #3
Nope, no cash back. Paid roughly Invoice cost and got a very fair amount on my trade (I was shocked). Dealer was very cool and easy to work with.
 

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welcome to the fam! fellow speed owner as well... enjoy and drive it like its stolen. :drive: . btw.. great post w/ that article and all. very informative. what area do u live in?? looking to meet up with some fellow speeds.
 

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Congratulations! :spin:

If you think the car is fun now, just wait until 600mi rolls around. Romp on that car like there's no tomorrow and you'll have a grin that won't fall off for days ;)
 

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Congrats on your great purchase>. what color and where are you from?
 

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Thanks y'all, I appreciate the warm welcome. I'm originally from New Orleans, born and raised, but I moved up to Northern Illinois after Katrina. My house flooded and my job moved, so it's been a fun 7 months. My wife and kids just made it up a couple of weeks ago. They stayed down there to work with insurance and contractors to repair the house while I was working up north at my job.

Anyway, the car is the Titanium Gray with sunroof and Nav System. It's a blast to drive, I took my boss in a spin today and he was shocked that it was a 4 cylinder. I got on it pretty hard before the engine really warmed up, but I think it'll be okay.

sixium, what happens @ 600 mi.?
 

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That is when you can have a TON of fun with the car.. means the break in period is OVER!!
 

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Welcome and congrats. @600 miles is after break in. I did 2000 miles. Then you can romp on it. :drive:
 

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Welcome and congrats. @600 miles is after break in. I did 2000 miles. Then you can romp on it. :drive:
[/b]
Pfft, break-in period. LOL. I've asked all the techs that have worked in our service dept for 15-20 years and they say they're ready to go from the factory. Just go easy the first 500 miles (don't take it to redline) and it's good to go.
 

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My break it in the way you're gonna drive it theory has always served me well. With cars, trucks, motorcycles, boats, everything!! I wouldn't necessarily spend the first 500 miles on the tri-oval in Daytona going wheel to wheel with Tony Stewart, but I wouldn't be afraid to have a little fun during the break-in.
 

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Welcome to the club. Congrats on the new ride and sorry to hear about your 7 months of fun fun with FEMA. :)
 
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