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Journalists aren't exempt from the same childish giggle-fits that afflict regular car enthusiasts. All it takes is a loads of power (preferably enough to overwhelm the tires on command) and even the most jaded journalist will crack a smile. We think the normally aspirated Mazda 3 is a fantastic small car, so we just knew that the turbocharged Mazdaspeed 3 would be a guaranteed giggle.

The Mazdaspeed 3's engine puts out big peak numbers, and as expected, we loved its acceleration. Many of us noticed, though, that the turbocharged 2.3-liter sometimes felt like an on-off switch. At some speeds, it made amazing power. At others, it didn't. The dyno chart shows that we weren't imagining things.

Turbos, by nature, have reduced operating ranges, but the Mazdaspeed 3 seems to be particularly susceptible to that limitation. It has prodigious torque in the midrange, but the engine feels anemic below 3000 rpm or above 5500. Honda's normally aspirated Si makes at least 85% of its maximum torque from 2000 to its redline. That means that if you floor the Honda's loud pedal anywhere between two and eight grand, you'll have at your disposal at least 85% of the maximum quoted torque. VW's turbo GTI will hand over at least 70% of its peak number at any time from two grand to its own redline. The Mazda is far behind the others at 20%.

Of course, the 'Speed 3 makes a much higher peak torque number than either the VW or the Honda (in fact, its peak is almost twice what the Honda puts out). But the GTI's engine, which is 0.3 liter smaller than the Mazda's, actually makes more torque than the Mazda from idle to 2700rpm--and again from 5800rpm to redline. The result is that the VW responds to gas pedal inputs with proportional urgency while the Mazda is sometimes fantastically fast, and sometimes--quite surprisingly--not.

A dual-scroll turbocharger like the one in the Saturn Sky Red Line and Pontiac Solstice GXP would help the Mazdaspeed 3 in increasing its usable rev range. As you can see in the comparison graph between the 3 and the Sky Red Line, peak numbers are similar, but the shapes of the torque curves tell two very different stories. GM's dual-scroll turbo builds boost much earlier, and has almost reached its torque peak by 2000 rpm. At that speed, the Saturn's 2.0-liter generates 210 lb-ft, compared to the larger Mazda engine's 128. Torque is similar throughout the midrange once the Mazda finally wakes up at 3000. By 6000, Mazda's engine is running out of breath, putting out 138 lb-ft while the smaller GM engine still manages 168.

Punch the accelerator at 3000 rpm in a Mazdaspeed 3 and you'll probably smile, too. But if you compare it to the more sophisticated engines of the other cars here, you may find it lacking the linearity and broad-range power delivery that set apart the merely powerful engines from the truly magnificent.

http://www.automobilemag.com/features/0610...zdaspeed3_dyno/
 

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Intresting article. What they also forget to mention is that while you might have 85% tq in from 2-8k you need to flog it the entire rev range just to move the car quickly.

I guess it depends what your looking for... a usuable power band,high revving hp or lots and lots of TQ :)
 

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the turbos make them different cars. while the Civic might seem like its in the same market as the speed3 or even GTI, the lack of performance in comparison is so ridiculous to even suggest that the two are competitors.

Speed3 vs WRX. for right now, thats the direct competitor until dodge's ugly ass, i-sit-2-inches-higher-than-the-srt4-but-my-300hp-might-make-up-for-it, Caliber SRT.

i do like the dyno videos though. and 216/245 is pretty damn impressive for a fwd car. right over/at 15% drivetrain loss.
 

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Its almost exactly 18% loss on the hp, which is about what we've come to expect from Mazda. Those are nice numbers!
 

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its kind of odd to think about, the normal thing for a turbo eninge if you dont match up perfectly your power curve and you compresser curve is to get a smaller turbo to spool faster or a bigger turbo to make power further on down the road (not technical at all just saying something)

in mazdas case the turbo doesnt spool fast or make power up high
what gives...
the old dodges used a mitsu turbo for the auto cause it spooled just a bit faster than the garret in the manuals (they both had the same accelortion number)
and for the record the srt-4s didnt lose much of anything when they dynoed. so if they say the caliber srt4 will have 300hp
it would be safe to say the thing will make 270-280 to the wheels(assuming that dodge stays true to its heritage)
 

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its kind of odd to think about, the normal thing for a turbo eninge if you dont match up perfectly your power curve and you compresser curve is to get a smaller turbo to spool faster or a bigger turbo to make power further on down the road (not technical at all just saying something)

in mazdas case the turbo doesnt spool fast or make power up high
what gives...
the old dodges used a mitsu turbo for the auto cause it spooled just a bit faster than the garret in the manuals (they both had the same accelortion number)
and for the record the srt-4s didnt lose much of anything when they dynoed. so if they say the caliber srt4 will have 300hp
it would be safe to say the thing will make 270-280 to the wheels(assuming that dodge stays true to its heritage)
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This may be too early to say for sure yet, but maybe the stock intercooler set up is causing some restriction? CustomMSP just posted dyno results of their new aftermarket TMIC:
http://forum.mazda6club.com/index.php?show...1617&st=255 Post #266
and direct link to dyno plot:
http://forum.mazda6club.com/index.php?act=...st&id=16920
Please note that the absolute numbers aren't critical in this case. It's the relative difference between stock TMIC and aftermarket TMIC that's important. Almost 40lb/ft more at 3200rpm!

The gains in torque below 4000rpm are significant, and may also translate into similar gains below 3k rpm. Unfortunately the dyno stops too soon to say, but the results at 2800 rpm are teasingly good, 230lb/ft. Hopefully this also means a reduction in turbo lag. More info as the situation develops.
 

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This may be too early to say for sure yet, but maybe the stock intercooler set up is causing some restriction? CustomMSP just posted dyno results of their new aftermarket TMIC:
http://forum.mazda6club.com/index.php?show...1617&st=255 Post #266
and direct link to dyno plot:
http://forum.mazda6club.com/index.php?act=...st&id=16920
Please note that the absolute numbers aren't critical in this case. It's the relative difference between stock TMIC and aftermarket TMIC that's important. Almost 40lb/ft more at 3200rpm!

The gains in torque below 4000rpm are significant, and may also translate into similar gains below 3k rpm. Unfortunately the dyno stops too soon to say, but the results at 2800 rpm are teasingly good, 230lb/ft. Hopefully this also means a reduction in turbo lag. More info as the situation develops.
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I'm not saying his TMIC doesn't make a difference but check out all these stock dyno's, they all show close to full torque @ 3000rpm. These were all pre-flash.

http://forum.mazda6tech.com/viewforum.php?f=52
 

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i didn't want to start a new thread so i just found something related to the MS3 in here.

i, ONCE AGAIN, did not have a chance to attend my local autocross club today. haven't participated since july and its killing me. i just found pics of the event and lo and behold:




i don't give a shit what happens next month, im going to autocross.
 
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