CX-9 Skyactiv 2.5L turbo engine

[Chris_Top_Her]

I'm gonna go to the dealership, scream my turbo and tell them I 2.5t swapped it. Then when they ask to

all they'll see is mostly stock.

 

[Unobtanium]

That is very easy to answer. Because Mazda designed the tune to run on s*** gas. 87 octane. They did this to make it as cheap as possible for the consumer.

the MX5 ND has the 2.0L, just like the mazda 3. But mazda designed that for 91 octane, guess which engine puts more to the ground ?

You get more power out of it simply by "taking off the brakes" that mazda put on the tune so that it would run grocery getter gas

What about the European 91 tune? It only gained a few bhp.

 

[Unobtanium]

I could take pictures of the maps and show you where mazda Detuned certain areas. They actually ramped the VVT back up right at 6000 RPM but cut it off everywhere below except where it makes max torque. The mazda 3 2.0L does not put 150 ft lbs down on any dyno stock. You have to stop looking at the rated numbers and look at REAL WORLD numbers.

Look guys I could care less if you believe me or not, I have been tuning these engines for years, We just had our turbo skyactiv sedan at the track last night.

Believe whatever the hell you want.


Mazda has a 165 version and 120 version in the EU. Exact same engine. You think Mazda detuned one of them to 120 for safety reasons?...... I bet you don't even know what is limited in the tune that stops it from making 165...

Think about this for a moment. These engines have some of the highest compression ratios on the market, lightweight components. 14:1 compression for christ sake you and REALLY DON'T BELIEVE YOU CAN GET MORE POWER?? The Honda K20 makes over 230 WHP with bolt ons and 11:1 compression, without direct injection (which allows for more aggressive yet safe tuning).

14:1 compression ran on 87 octane. Mazda detuned the hell out of these engines. I'm really sorry to say this but you'd have to be pretty damn dumb or clueless to think they are near their potential on 87 OCTANE!!!

By the way, the difference in the tune with the US vs EU market ones aint much.

Now once again, I have tuned these engines for years, so I think I just might have a bit more understanding on these than what you can read on google. And I say that because i'm 99.99% certain none of you have put one on an engine dyno, torn it down and measured the specs, weighed the components, flowed the head, etc.

Unless some of you have? Please share.

Why would mazda DE tune the engine in certain areas for zero benefit? I worry that longevity was the trade.

 

[Unobtanium]

Great post...and YES, The K20 can make that power, and the K24 can make about 15hp more. Bad little mama jamma's...

You're right, these guys just won't get it no matter what you provide. No worries, I too have seen this with my own eyes...keep on keepin' on with the mad science...

The K series is very straightforward. The DI motor has inherent hurdles, some of which tuning is directly responsible for solving. The K? You just tune the s*** out of it. Get as aggressive as possible without knock retard and keep the a/f from going lean and all is well. Super simple, comparatively.

 

[jhu8]

Why would mazda DE tune the engine in certain areas for zero benefit? I worry that longevity was the trade.

I think a lot of cars are detuned. I can't say for sure but I think it's a good assumption. My 08 Mustang GT got a 17hp bump simply from a tune. Those tunes most likely just retuned areas on the engine that Ford had set conservative. I know my buddies F150 had a tune put on it as well that yielded similar gains. I would think many cars have some untapped power that the manufactures don't unleash because at those engine settings, it's most optimal when accounting for the thousands of different driving location and scenarios someone could put the car in. My guess is the manufactures have plenty of data that shows what optimal engine settings are and they set them at that point.

 

[Unobtanium]

I think a lot of cars are detuned. I can't say for sure but I think it's a good assumption. My 08 Mustang GT got a 17hp bump simply from a tune. Those tunes most likely just retuned areas on the engine that Ford had set conservative. I know my buddies F150 had a tune put on it as well that yielded similar gains. I would think many cars have some untapped power that the manufactures don't unleash because at those engine settings, it's most optimal when accounting for the thousands of different driving location and scenarios someone could put the car in. My guess is the manufactures have plenty of data that shows what optimal engine settings are and they set them at that point.

You're also talking about a 4.6L V8 that made around 300 SAE NET and comparing it to a 4 banger that makes mid 180's SAE NET. And then you're adding nearly 50% to that gain.

 

[ALafya]

Mazda has a 165 version and 120 version in the EU. Exact same engine. You think Mazda detuned one of them to 120 for safety reasons?...... I bet you don't even know what is limited in the tune that stops it from making 165...

The reason for a 120HP version is taxes.
In the UK, Germany and in other EU countries they tax the hell out of everyone and tax "everything that moves" based on fuel type, consumption, HP and CO2 emissions. In other parts of the world, base trims have a 1.5L engine with up to 120HP and the sporty version is the 2L. There is no 2.5L version.
In the UK, the version with more power puts you into a different Tax Band for your vehicle. Yes, the government there decides what is "excessive" and tax you for it. Glad to be an American!

 

[GAXIBM]

The MX-5 2.0L has one key hardware difference. and I'm positive nobody here even knows what it is.

.

The big 4-2-1 header is in the CX5 and there is no room for it in the MX5. There also was not room for it in the first 3 until they redesigned it to provide room in front of the firewall. The big header allows better exhaust gas evacuation without the pulse of the next exhaust valve opening adding backpressure.

 

[NelsonLewis]

The K series is very straightforward. The DI motor has inherent hurdles, some of which tuning is directly responsible for solving. The K? You just tune the s*** out of it. Get as aggressive as possible without knock retard and keep the a/f from going lean and all is well. Super simple, comparatively.

Wasn't trying to compare engines. Was just stating that the K20 CAN produce 230hp with bolt ons and it was called "BS." The only thing BS is that statement that it can't, and others calling everything TBot101 post as "BS", because I know from first hand experience that it is not...

 

[CC58]

The big 4-2-1 header is in the CX5 and there is no room for it in the MX5. There also was not room for it in the first 3 until they redesigned it to provide room in front of the firewall. The big header allows better exhaust gas evacuation without the pulse of the next exhaust valve opening adding backpressure.

Well that s*cks. The first CX-5 without the 4-2-1 header lacked low end torque and didn't have 13:1 compression pistons I believe. Maybe in the MX5 it would be okay since its so much lighter. Its too bad they couldn't fit the header.

 

[jhu8]

@Uno..True. I'll be honest I haven't read through this whole thread. I'm just saying that I think all engines have some untapped power that manufacturers purposely don't tap into.

 

[Lbear]

@Uno..True. I'll be honest I haven't read through this whole thread. I'm just saying that I think all engines have some untapped power that manufacturers purposely don't tap into.

Well put. Manufacturers put in a margin of safety for long-term reliability. The same goes for engineers. When the engineer a home or bridge, they have a "safety factory" built into their calculations. Some say about 25%.

 

[Unobtanium]

@Uno..True. I'll be honest I haven't read through this whole thread. I'm just saying that I think all engines have some untapped power that manufacturers purposely don't tap into.

I agree strongly with that. However, DI engines also have combustion issues (carbon build up) that manufacturers like Mazda specifically tune AROUND. How do we know that the power they left on the table, was just something they tuned around?

For example: You buy a WS.6 Trans Am. It's pretty quick, but you feel like the car could be quicker. So, you have the shift-points changed a bit, and firmed up, and torque management disabled. Holy crap! You just dropped nearly 1/4 second in the 1/4 mile. But now you blow the 7.5 rear end out of it because that torque management really, truly, honestly...had a purpose. Protecting that weak rear diff.

I am concerned that Mazda's "25bhp" "left on the table" might just have a purpose...less efficient valve-timing in exchange for preventing carbon build-up.

That is my concern. Not OVT's hp claims.

 

[Tbot101]

I agree strongly with that. However, DI engines also have combustion issues (carbon build up) that manufacturers like Mazda specifically tune AROUND. How do we know that the power they left on the table, was just something they tuned around?

For example: You buy a WS.6 Trans Am. It's pretty quick, but you feel like the car could be quicker. So, you have the shift-points changed a bit, and firmed up, and torque management disabled. Holy crap! You just dropped nearly 1/4 second in the 1/4 mile. But now you blow the 7.5 rear end out of it because that torque management really, truly, honestly...had a purpose. Protecting that weak rear diff.

I am concerned that Mazda's "25bhp" "left on the table" might just have a purpose...less efficient valve-timing in exchange for preventing carbon build-up.

That is my concern. Not OVT's hp claims.

Well if you did some research you'd realize that is not the case. Mazda has very specific placement of the intake valves to keep them hot (over 400*). They are "deep" into the cylinder head and port. This helps prevent the carbon build up mostly. Along with some cam timing in low load. Low load. Too bad it's already been shown on bone stock vehicles the build up still happens.


Chris_Top_her has had our tune on his CX5 since it practically left the lot, and it's not only doing just fine it's about to be turbocharged...

 

[jhu8]

I agree strongly with that. However, DI engines also have combustion issues (carbon build up) that manufacturers like Mazda specifically tune AROUND. How do we know that the power they left on the table, was just something they tuned around?

For example: You buy a WS.6 Trans Am. It's pretty quick, but you feel like the car could be quicker. So, you have the shift-points changed a bit, and firmed up, and torque management disabled. Holy crap! You just dropped nearly 1/4 second in the 1/4 mile. But now you blow the 7.5 rear end out of it because that torque management really, truly, honestly...had a purpose. Protecting that weak rear diff.

I am concerned that Mazda's "25bhp" "left on the table" might just have a purpose...less efficient valve-timing in exchange for preventing carbon build-up.

That is my concern. Not OVT's hp claims.

Yeah I definitely agree with you. I think it's the case for all car manufactures. Whether it's for safety reasons for the engine to maintain longevity, fuel efficiency, optimal engine output for the variety of environments the car may run in(-20 degrees F all the way up to the low 100s). But being that the skyactive engine is relatively new, who really knows. Just have to trust Mazda's set numbers. That's why there is no way I would go throwing a tune on my CX-5. IMO there is no point with the risks associated for slight gain. The tune isn't going to turn it into some fast car, therefore imo it is not worth the risks associated. Not like other sports cars where the engines are built for performance. I threw a tune on my mustang with ease of mine because I knew that engine is built to be pushed hard.

 

[CC58]

I agree strongly with that. However, DI engines also have combustion issues (carbon build up) that manufacturers like Mazda specifically tune AROUND. How do we know that the power they left on the table, was just something they tuned around?

For example: You buy a WS.6 Trans Am. It's pretty quick, but you feel like the car could be quicker. So, you have the shift-points changed a bit, and firmed up, and torque management disabled. Holy crap! You just dropped nearly 1/4 second in the 1/4 mile. But now you blow the 7.5 rear end out of it because that torque management really, truly, honestly...had a purpose. Protecting that weak rear diff.

I am concerned that Mazda's "25bhp" "left on the table" might just have a purpose...less efficient valve-timing in exchange for preventing carbon build-up.

That is my concern. Not OVT's hp claims.

I had a 2000 LS1 Camaro. Chevy saved money by using that weak 7.5 Monza rear end. They protected rearend from manual transmission by putting a small diameter clutch, and high gears in transmission. If you got on it to hard, the clutch would slip instead of spinning the tires, ouch. The trannys gears were way to high requiring 4:10 gears in rear end, but the 7.5 was to small to reliability use 4:10 gears. If you tried to replace the rear end you lost ABS. They strangled engine so it wouldn't match Corvette with same engine. Adding cat back and air lid got a good bit of hp back.

 

[MikeM.]

OVT increases performance across the entire RPM range. My concern is...why didn't Mazda? 25hp is a LOT to "leave on the table" without a good reason, and these engines are not something that Mazda cobbled together from several platforms and pitched out the door.

25 HP? Do you mean 25-35 HP? (rofl2)

Did you ever consider that Mazda didn't want to compete too vigorously with the competition or that Mazda allocated all their inexperienced engineers to developing Skyactiv? (rofl2)

 

[MikeM.]

Well that s*cks. The first CX-5 without the 4-2-1 header lacked low end torque and didn't have 13:1 compression pistons I believe.

All CX-5's have the Skyactiv 4-2-1 header. In fact, the CX-5 was the first Mazda with the complete suite of Skyactiv technologies (chassis, engine (including header), transmission).

 

[Tbot101]

All CX-5's have the Skyactiv 4-2-1 header. In fact, the CX-5 was the first Mazda with the complete suite of Skyactiv technologies (chassis, engine (including header), transmission).

I dont think the older 2.0L CX5 did. they got the low compression gutless engine.

 

[MikeM.]

I dont think the older 2.0L CX5 did. they got the low compression gutless engine.

I own one of the early 2013 2.0L CX-5's (built in 2012). Every North American CX-5 had the 4-2-1 Skyactiv exhaust header. Was there some early release version (perhaps sold in Asia) without the Skyactiv header? Not that I've ever heard about.

What makes you think differently?

And the lowest compression gasoline engine ever sold in a CX-5 is the North American version designed to run on regular fuel. At 13:1 I don't know any serious auto enthusiast who would call that "low compression".