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So why all the massive torque under 3.5 K ? The skyactiv head and exhaust headers ?
Is what is maximizing torque and HP under 4K also restricting the engine above 4k?
Made an account just to answer this cause ive been doing a lot of research on this car.

They created this weird down pipe/ turbo hybrid called dynamic pressured turbo that allows boost build up at 1k revs. This is then released and causes a huge amount of boost/torque. Then there is actually a huge cut off. Its good for track racing where you can get going fast after turns but not really good for drag. This engine was suppose to be put in the MAZDA TCR but they decided to put a nonproduction engine... That might be a bad sign. I also own this vehicle.

Here is a video explaining the science
 

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Made an account just to answer this cause ive been doing a lot of research on this car.

They created this weird down pipe/ turbo hybrid called dynamic pressured turbo that allows boost build up at 1k revs. This is then released and causes a huge amount of boost/torque. Then there is actually a huge cut off. Its good for track racing where you can get going fast after turns but not really good for drag. This engine was suppose to be put in the MAZDA TCR but they decided to put a nonproduction engine... That might be a bad sign. I also own this vehicle.

Here is a video explaining the science
Interesting ... Thanks !
I see that yes that low end boost great for hairpin and tight turns to accelerate out of .. but alot of tracks have long & medium straights and they may not be 1/4 mile but still long enough to rev engine past 4K . The TCR is a 7K revver with 350HP/490torque ... The AWD Turbo is certainly detuned.
 

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This engine was suppose to be put in the MAZDA TCR but they decided to put a nonproduction engine... That might be a bad sign.
TCR class rules limit engine size to 2.0L and power to 345 hp and 310 ft/lbs of torque. Since Mazda doesn't produce a 2.0L turbocharged engine of any sort an in-house motor was never an option so an existing TCR approved VW engine was used.
 

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They created this weird down pipe/ turbo hybrid called dynamic pressured turbo that allows boost build up at 1k revs. This is then released and causes a huge amount of boost/torque. Then there is actually a huge cut off.
Thats not really how it works....there is no "build up and release"...
The dynamic pressure turbo works by installing a valve body upstream of the turbocharger in the exhaust manifold. At low rpm, below ~1600, the valves in effect reduce the cross section of the flow path, increasing the exhaust gas velocity. This allows the turbo to spool up much faster at low rpm and make more power in the low part of the rpm band. Once the motor gets to about 1600 rpm the valve body opens the exhaust stream to normal size and the turbo spins in a normal fashion.

Now if you could keep those valves closed a bit longer you might get the power peak moved higher in the rpm range....
 

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Its good for track racing where you can get going fast after turns but not really good for drag. This engine was suppose to be put in the MAZDA TCR but they decided to put a nonproduction engine... I also own this vehicle.
Really? I personally find the engine to be really underwhelming, especially compared to the many exceptional 2.0T engines out there -from Honda's to the Audi/VW 2.0T. There is torque and power from 1500 to 4000 but the engine is basically out of steam anywhere around 4.5-5K. Can't imagine this in a true performance car.

The 2.0 NA engine in the Miata is a thing of beauty. I would love to see a turbo on that!
 

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Really? I personally find the engine to be really underwhelming, especially compared to the many exceptional 2.0T engines out there -from Honda's to the Audi/VW 2.0T. There is torque and power from 1500 to 4000 but the engine is basically out of steam anywhere around 4.5-5K. Can't imagine this in a true performance car.

The 2.0 NA engine in the Miata is a thing of beauty. I would love to see a turbo on that!
Turbo or supercharger for the MX5 NC/ND 2.0L check out Fab9 Tuning Fab9Tuning GT Turbo Kit (NC 06-15)
 

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TCR class rules limit engine size to 2.0L and power to 345 hp and 310 ft/lbs of torque. Since Mazda doesn't produce a 2.0L turbocharged engine of any sort an in-house motor was never an option so an existing TCR approved VW engine was used.
The MZ-2.0T doesnt qualify as in house? ....
 

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The 2.0 NA engine in the Miata is a thing of beauty. I would love to see a turbo on that!

Turbo or supercharger for the MX5 NC/ND 2.0L check out Fab9 Tuning Fab9Tuning GT Turbo Kit (NC 06-15)
That kit is for the MZR powered MX-5 NC. Nothing to do with an SA-G motor. I don't believe Fab9 makes a FI kit for the ND. Edelbrock has a supercharger kit for the current ND cars though. BBR, AVO, JDL and Turbo Source have turbocharger kits also.
 

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No it doesn't. Mazda never produced such a thing, and in any case Mazda hasn't made an MZR motor of any sort in 10 years.
Made for Mazda , Made with Mazda , Made with Mazda name on it. MZ-2.0T or MZR-R

I assume you are saying .. not made in a Mazda factory production line.
 

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Made for Mazda , Made with Mazda , Made with Mazda name on it. MZ-2.0T or MZR-R

I assume you are saying .. not made in a Mazda factory production line.
LOL I know what the MZ 2.0T is....and its hardly a Mazda production motor. Its wasn't made by Mazda but by AER in the UK and has nothing in common with the MZR L engine that Mazda used in passenger cars.
And yes, TCR has homologation requirements....minimum production requirement of 5000 cars/engines/parts per 12 consecutive calendar months.
 

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LOL I know what the MZ 2.0T is....and its hardly a Mazda production motor. Its wasn't made by Mazda but by AER in the UK and has nothing in common with the MZR L engine that Mazda used in passenger cars.
And yes, TCR has homologation requirements....minimum production requirement of 5000 cars/engines/parts per 12 consecutive calendar months.
LOLOL ... of course Sensei
 

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you guys might find this intersting
Thats not really how it works....there is no "build up and release"...
The dynamic pressure turbo works by installing a valve body upstream of the turbocharger in the exhaust manifold. At low rpm, below ~1600, the valves in effect reduce the cross section of the flow path, increasing the exhaust gas velocity. This allows the turbo to spool up much faster at low rpm and make more power in the low part of the rpm band. Once the motor gets to about 1600 rpm the valve body opens the exhaust stream to normal size and the turbo spins in a normal fashion.

Now if you could keep those valves closed a bit longer you might get the power peak moved higher in the rpm range....

I respectfully beg to differ because its a pressure release. They are able to control pressure and release a large amount through a bigger tunnel. Pressure is directly related to air velocity. I think that maybe saying that its controlled would be a better phrasing but I don't think releasing the pressure into a wider tunnel is wrong to say
 

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I respectfully beg to differ because its a pressure release. They are able to control pressure and release a large amount through a bigger tunnel. Pressure is directly related to air velocity. I think that maybe saying that its controlled would be a better phrasing but I don't think releasing the pressure into a wider tunnel is wrong to say
Again, no....
How it works it by funneling the exhaust through a smaller opening at low rpm. This has the same effect as a nozzle on a garden hose. No nozzle, no pressure. Put a 1/4" diameter nozzle on a 1" garden hose and you get more pressure from the stream and a lot more velocity. In this case, the same amount of exhaust gas moving through a smaller passage results in a much faster gas flow, which in turn spins the turbo up much faster and at lower rpms, resulting in much more low end power and no turbo lag. Once the rpms hit 1620, the larger passages open up and exhaust flow return to normal.

 
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