CX-9 Skyactiv 2.5L turbo engine

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2014.5 2.5L Touring /w bose
Really interesting video by TFL on 2016 CX-9 new Skyactiv 2.5L turbo engine.
New engine makes 250hp @ 310ft.lbs of torque.

Summary of video is;

o 13:1 reduced to 10.5:1 to run turbo
o water cooled EGR saves gas
o 250hp on 93, 225hp on 87 octane
o 310ftlb off the line

Mazda seems to always be on the leading edge, and the water cooled EGR is a good example. Turbos usually run rich when under boost to keep engine cool and wastes fuel, but Mazda found a way to run lean by water cooling EGR return gases.

Would be interesting if they offered this engine in a CX-5 tuned for high end power instead of low end torque.
This engine was build from ground up to withstand turbo power. Would be interesting to see a CX-5 with swapped engine!
 
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Me first lol. I'm curious to see what aftermarket tuning and a or a turbo sizing swap can do.
 
Surfing for new CX9, found this article.

Mazda calls its variable nozzle turbocharging Dynamic Pressure Turbo technology. By varying and strategically directing the amount of exhaust pulse used to run its turbocharger, the 2.5-liter Skyactiv-G engine can spool up more quickly at low rpm. The method works by sending exhaust air to the turbine through three smaller exhaust ports at low rpm, quickly creating boost pressure of up to 17.4 psi. Three larger ports open up via a flow control valve when the revs climb.

Wow, 17.4psi, but only at low rpm. If this thing were kept bottled up, it would make 400hp+ at high rpm!
Talk at end mentions putting it in Speed3. It would be cool to put it in the MX5, IMO.
 
Surfing for new CX9, found this article.



Wow, 17.4psi, but only at low rpm. If this thing were kept bottled up, it would make 400hp+ at high rpm!
Talk at end mentions putting it in Speed3. It would be cool to put it in the MX5, IMO.

What's the psi drop off on the high end? Guessing down to 13ish. You're right, this thing would put out some power if it was the same all the way to redline, and would pull like a raped ape...
 
You should be able to get an easy 10-15 extra HP just by putting it on a dyno (with no mods). (lol2)

I know this is a low blow directed at OVT (tbot1) and Chris, but you can easily double that number, and the same with torque to go along with it on a simple ecu flash on a turbo motor.
 
I hope Mazda puts this motor in their other models as part of their "MazdaSpeed" line.
 
I know this is a low blow directed at OVT (tbot1) and Chris, but you can easily double that number, and the same with torque to go along with it on a simple ecu flash on a turbo motor.

You missed the punch line. Reread it. I'm guessing OVT got booted for potty mouth. This is a mainstream forum, so I can see why it happened. Still, he seemed like a nice guy. Honest? That will remain a question.
 
You missed the punch line. Reread it. I'm guessing OVT got booted for potty mouth. This is a mainstream forum, so I can see why it happened. Still, he seemed like a nice guy. Honest? That will remain a question.

I didn't miss anything...all claims mentioned are attainable. Been there, done that...
 
Really interesting video by TFL on 2016 CX-9 new Skyactiv 2.5L turbo engine.
New engine makes 250hp @ 310ft.lbs of torque.


What's cool is that this 2.5L GAS powered engine makes almost as much power as the new Duramax 2.8L Diesel Turbo engine (180hp - 365 ft.lbs). The SkyActiv makes more HP so it will pull harder in the higher RPM than the diesel.

I don't doubt this engine will make its way into the Mazda3 Speed and will be putting out more HP/Torque. I remember reading close to 300HP and 350 ft.lbs with AWD in the Mazda3 Speed. It will make for a fast car.
 
You missed the punch line. Reread it. I'm guessing OVT got booted for potty mouth. This is a mainstream forum, so I can see why it happened. Still, he seemed like a nice guy. Honest? That will remain a question.

I was not booted.
glad to see some folks (MikeM) still trying to satisfy his ego with his classic remarks.


In Other news we are really excited for this engines release, and can't wait to see what we find in the ECU. Judging by the hardware alone, Mazda severely under tuned it (like most of their engines).
 
What's the psi drop off on the high end? Guessing down to 13ish. You're right, this thing would put out some power if it was the same all the way to redline, and would pull like a raped ape...

It would have been easy for Mazda to keep boost pressure high through the rev range and have big HP claims. There's more than one reason why they didn't.

One reason is thermal management in the combustion area. More power = more heat and it has to go somewhere fast. The water jacket carries it away as fast as it can but the heat can only travel so fast through the aluminum before it starts building up around the combustion chamber and causing nasty problems. A stock tune is designed to pull up a long grade at full power continuously (and it's tested on a brake dyno and in the real world extensively to catch possible problems). Tune for more power and you will start pushing the limit of how fast heat can leave the combustion area. A bigger radiator not going to solve this problem.

All the other components would have to be beefed up to handle the extra power and to dissipate heat (not engine heat, the heat from gear friction, etc.). A heavier duty transmission, differentials, brakes, etc. costs a lot more, weighs a lot more and has more friction. This causes everyday MPG to drop (and it would be very expensive to upgrade all these components after the vehicle is produced).
 
It would have been easy for Mazda to keep boost pressure high through the rev range and have big HP claims. There's more than one reason why they didn't.

One reason is thermal management in the combustion area. More power = more heat and it has to go somewhere fast. The water jacket carries it away as fast as it can but the heat can only travel so fast through the aluminum before it starts building up around the combustion chamber and causing nasty problems. A stock tune is designed to pull up a long grade at full power continuously (and it's tested on a brake dyno and in the real world extensively to catch possible problems). Tune for more power and you will start pushing the limit of how fast heat can leave the combustion area. A bigger radiator not going to solve this problem.

All the other components would have to be beefed up to handle the extra power and to dissipate heat (not engine heat, the heat from gear friction, etc.). A heavier duty transmission, differentials, brakes, etc. costs a lot more, weighs a lot more and has more friction. This causes everyday MPG to drop (and it would be very expensive to upgrade all these components after the vehicle is produced).

You don't have to tell me anything...no one, including Mazda is letting a turbo produce the same boost to redline from the factory, however, your claim of severe problems, new transmissions, loss of MPG, etc are straight up bogus. There are thousands and thousands of Evos, STIs, GTIs, SR4s, etc doing it, and some have been for over 6 figure mileage. I for one, am one, and do believe in the mad science of proper tuning...

Btw, who cares about max power? It's all about the power curve and drive ability across the board. The charts that Tbot1 provided, whether bogus or not according to your claims, were absolutely beautiful in that department...
 
It would have been easy for Mazda to keep boost pressure high through the rev range and have big HP claims. There's more than one reason why they didn't.

One reason is thermal management in the combustion area. More power = more heat and it has to go somewhere fast. The water jacket carries it away as fast as it can but the heat can only travel so fast through the aluminum before it starts building up around the combustion chamber and causing nasty problems. A stock tune is designed to pull up a long grade at full power continuously (and it's tested on a brake dyno and in the real world extensively to catch possible problems). Tune for more power and you will start pushing the limit of how fast heat can leave the combustion area. A bigger radiator not going to solve this problem.

All the other components would have to be beefed up to handle the extra power and to dissipate heat (not engine heat, the heat from gear friction, etc.). A heavier duty transmission, differentials, brakes, etc. costs a lot more, weighs a lot more and has more friction. This causes everyday MPG to drop (and it would be very expensive to upgrade all these components after the vehicle is produced).



Tell that to every subaru wrx , sti, speed3, evo, hyundai genesis BT, VW APR tuned, etc etc etc etc etc etc etc etc etc etc etc

Good info pulled off google though, did you conclude that with your degree in thermodynamics and testing cylinder temperatures for xxx and yyy aluminum blocks at XZY boost pressure and ABC ignition timing with XYZ fueling? Or maybe you didn't know there has been revolutionary changes in cylinder head and cylinder flow efficiency along with design characteristics integrated into pistons that propagate the flame front more efficiently, not to mention what you can get away with direct injection and cylinder cooling ( that is something the skyactiv engine uses already. Injection characteristics to cool the cylinder, because you probably weren't aware. That's hard to find on google)
 
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You should be able to get an easy 10-15 extra HP just by putting it on a dyno (with no mods). (lol2)

I don't even get why you are trying to talk s***. That comment isn't even properly directed and I'm not sure why at me, as I haven't even dynod my current car. When did I ever imply a dynon gives any kind of gain? Flame post, plain and simple.
 
You missed the punch line. Reread it. I'm guessing OVT got booted for potty mouth. This is a mainstream forum, so I can see why it happened. Still, he seemed like a nice guy. Honest? That will remain a question.

Hey, not sure if id8call him a potty mouth, but as far as mainstream, until I made a comment about a year or 2 ago there was actually a porn sub forum on this website (it was more of making fun of the fact it was here, but the admin noticed the bump and decided it no longer belonged here. Mazda3revoltuin actually still has a subforum like that ofc its been dead for a while).
 
That comment isn't even properly directed and I'm not sure why at me, as I haven't even dynod my current car. When did I ever imply a dynon gives any kind of gain? Flame post, plain and simple.

Chris, I made a funny joke because you were discussing what the T 2.5L Skyactiv would do with the proper mods. The joke wasn't personally directed at you, it was in response to your comment. Essentially, heck, without even modding the engine, one might see 10-15 HP gain just by putting it on a dyno! Get it? (nana)

Please don't take things so personally. It's well known and common knowledge that dynos are often used to 1) Show gains that don't exist or 2) exaggerate smaller gains into larger gains. Not always but sometimes. Of course they can also be used carefully and honestly in which case you might only see a few HP (plus or minus) from consecutive runs of the same vehicle without modifying anything.
 
You don't have to tell me anything...no one, including Mazda is letting a turbo produce the same boost to redline from the factory, however, your claim of severe problems, new transmissions, loss of MPG, etc are straight up bogus.

Where did I say anything about "severe problems, new transmissions"? It's commonly recognized that everything has a design limit. Increase power too much and you're going to shorten it's life and/or break it. Manufacturers try to be somewhat conservative so their stuff can handle more power but there is a limit to anything. And if you start putting twice the power through something, it may not break but it won't last as long as it would in it's intended usage.

This is common frickin' knowledge, I'm not sayin' anything controversial.

Please tell me what Mazda's design limitation was that kept the boost limits as low as they are in the upper rpm range? Common sense says there is a good reason why Mazda didn't run higher pressure for a bit more power (because we all know it would work).

Btw, who cares about max power?

Obviously, plenty of idiots with money in their pockets care about peak HP. If they didn't, there would be no point in advertising peak gains! Yet plenty of retailers advertise exactly that!
 
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