Torque curves for 2.5L Mazda engines

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CX-5 Signature
With regular fuel in manual mode the rpm cut off is at 6000rpm on my 2018 cx-9. The manual mode won’t shift for you, you can stay on the cut-off for as long as you want. Don’t know if that 6000 rpm limit is increased with better fuel, but honestly there isn’t much to gain at higher rpm with this engine, all the good stuff is down low in the rev range.
That's great to hear and I assume it will be the same for the CX-5. (y)
 
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Texas
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'20 CX-5 Signature
Here is just the torque curve for the 2.5T:

View attachment 222337
Before I purchased my CX-5, I saw a couple of YouTube reviewers question why the transmission upshifted well before redline as if they were annoyed or thought there was something wrong with the vehicle. I suspected the short shift was intentional to maximize performance. Many people associate higher RPM and engine noise with better acceleration - they think a vehicle is faster if it shifts at fuel cut-off. My turbocharged 2017 Civic Si was like this - it redlined over 6,000 RPM, but it was out of breath after 5,000 RPM and was faster when short-shifted.

After purchasing my CX-5, I noticed that the engine pulled impressively hard up until about 4,000 RPM then fell on its face from 4,000 to just over 5,000 RPM then it would upshift and take off again. This non-linear acceleration resulted in a roller coaster of grins and frowns while accelerating.

I had been running 87 octane since purchase in the vehicle with no problem. Normally, I don't drive my CX-5 aggressively, but was curious to see if I could notice a difference using 93 octane, so I ran the 87 out and refilled with 93. The engine adapted within minutes.

As this graph suggests, I noticed no difference in fuel economy or performance in normal driving below 4,000 RPM. My daily commute averages about 24 MPG either way. On 93 octane, however, the engine doesn't feel like it's running out of steam above 4,000 RPM and accelerates with much better linearity.

I'm not sure if I'll continue running 93 octane or revert to 87. Running 93 encourages less-efficient driving and the performance on 87 is more than adequate for how I normally drive. The 23 extra HP and extended torque curve afforded by 93 octane is certainly noticeable and appreciated during aggressive driving, but I didn't buy the CX-5 to race so a fraction of a second improvement in acceleration times means nothing to me and for the majority of other SUV drivers. However, I do like that the engine doesn't feel like it's running out of gas above 4,000 RPM while running 93. :)
 
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CX5 GT-R
Before I purchased my CX-5, I saw a couple of YouTube reviewers question why the transmission upshifted well before redline as if they were annoyed or thought there was something wrong with the vehicle. I suspected the short shift was intentional to maximize performance. Many people associate higher RPM and engine noise with better acceleration - they think the vehicle is faster if the shift at fuel cut-off. My turbocharged 2017 Civic Si was like this - it redlined over 6,000 RPM, but it was out of breath after 5,000 RPM and was faster when short-shifted.

After purchasing my CX-5, I noticed that the engine pulled impressively hard up until about 4,000 RPM then fell on its face from 4,000 to just over 5,000 RPM then it would upshift and take off again. This non-linear acceleration resulted in a roller coaster of grins and frowns while accelerating.

I had been running 87 octane since purchase and the vehicle with no problem. Normally, I don't drive my CX-5 aggressively, but was curious to see if I could notice a difference using 93 octane, so I ran the 87 out and refilled with 93. The engine adapted within minutes.

As this graph suggests, I noticed no difference in fuel economy or performance in "normal" driving below 4,000 RPM. My daily commute averages about 24 MPG either way. On 93 octane, the engine doesn't feel like it's running out of steam above 4,000 RPM and accelerates with much better linearity.

I'm not sure if I'll continue running 93 octane or revert to 87. Running 93 encourages less-efficient driving and the performance on 87 is more than adequate for how I normally drive. The 23 extra HP and extended torque curve afforded by 93 octane is certainly noticeable and appreciated during aggressive driving, but I didn't buy the CX-5 to race so a fraction of a second improvement in acceleration times means nothing to me and for the majority of other SUV drivers. However, I do like that the engine doesn't feel like it's running out of gas above 4,000 RPM while running 93. :)
Nothing about the CX5 turbo requires it to shift at 5500ish, though. That engine isn't out of breath. Boost is being cut prematurely. It's got a lot more performance potential if they were to run it up to 6-6500ish.
 
Nothing about the CX5 turbo requires it to shift at 5500ish, though. That engine isn't out of breath. Boost is being cut prematurely. It's got a lot more performance potential if they were to run it up to 6-6500ish.
The way it is tuned out of the factory you don’t really gain anything by reving up to the redline. If you tune it differently as you mention it is a different story. Do you know of a tune that gains the performance you are mentioning? Asking seriously because i know a lot of people have been asking on this forum and I didn’t think anyone had been able to really get any serious leads. (I may be wrong, i can’t read every posts).
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
The way it is tuned out of the factory you don’t really gain anything by reving up to the redline. If you tune it differently as you mention it is a different story. Do you know of a tune that gains the performance you are mentioning? Asking seriously because i know a lot of people have been asking on this forum and I didn’t think anyone had been able to really get any serious leads. (I may be wrong, i can’t read every posts).
From what I've read, there are no current tuning options, but those closest to coming up with something are DR Tuned and CorkSport (as mentioned by @speed3chris1) and Burger Tuning (as mentioned by @jcrout7992).
 
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'14 Mazda CX-5 GT
Assuming the '21 Mazda 3 gets the same 2.5T as the rest of the Mazda line-up, we should see more tuners start to work on these engines.
 
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Texas
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'20 CX-5 Signature
Assuming the '21 Mazda 3 gets the same 2.5T as the rest of the Mazda line-up, we should see more tuners start to work on these engines.
The 2.5T is also used in the 6 and CX-9, but there just aren't a lot them running around. All CX-9s have had the 2.5T for nearly five years, but there aren't a lot of CX-9s and I'd be surprised if the typical CX-9 owner would have any interested in tuning their three-row SUV. Only about 6% of CX-5s and a third of Mazda6s are equipped with the 2.5T engine.
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
All I ask for was the torque curves for a 2.5 NA engine and I get this?
Well, to be fair..

Looking for the torque vs RPM for the 2.5L NA and 2.5L turbo engines.
dougal posted a 2.5T dyno chart that shows the 87 octane torque curve (in red)..

Here is just the torque curve for the 2.5T:

View attachment 222337
.. then Chris_Top_Her stated the following in bold..

The bottom line is like the OEM curve on on the 2.5NA, and the top is a good tune.
Now we need the torque curve for the 2.5L non turbo. I want to compare torque at the lower RPMs of each.
Assuming Chris is correct (no reason to doubt him), the torque curve is very similar. The only difference is the actual torque number (2.5NA at 185 ft-lb vs 2.5T at 310 ft-lb).
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg. Plano, TX
Contributor
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Plano, Texas, USA

Assuming Chris is correct (no reason to doubt him), the torque curve is very similar. The only difference is the actual torque number (2.5NA at 185 ft-lb vs 2.5T at 310 ft-lb).
No, the torque curve between 2.5L and 2.5T is totally different. For 2.5L the peak torque is 186 lb-ft @ 4,000 rpm, but for 2.5T the peak torque is 310 lb-ft @ 2,000 rpm (87 octane).
 
No, the torque curve between 2.5L and 2.5T is totally different. For 2.5L the peak torque is 186 lb-ft @ 4,000 rpm, but for 2.5T the peak torque is 310 lb-ft @ 2,000 rpm (87 octane).
You are right. I think what chris_top_her was refering too is the horsepower curb on the 2.5T graph. Meaning the torque curve of the 2.5NA has the same shape as the power curve of the 2.5T. A bit confusing i agree.


I found this for the 2.5 NA, but not sure how accurate this website is ( i hate it). The values were calculated, not measured. It assumes a gradual increase in torque to max torque, which i don’t think is the case in reality. Note the difference in units for torque value, conversion is required to compare.
 
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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg. Plano, TX
Contributor
:
Plano, Texas, USA
You are right. I think what chris_top_her was refering too is the horsepower curb on the 2.5T graph. Meaning the torque curve of the 2.5NA has the same shape as the power curve of the 2.5T. A bit confusing i agree.


I found this for the 2.5 NA, but not sure how accurate this website is ( i hate it). The values were calculated, not measured. It assumes a gradual increase in torque to max torque, which i don’t think is the case in reality. Note the difference in units for torque value, conversion is required to compare.
Thanks for finding a power / torque curve for 2.5L. The graph should be accurate other than using metric units. And the shape of the curves, power and torque, are very typical for a naturally aspirated engine.

566778C1-170A-4A86-92CD-42E495B8FFF0.jpeg


And just for easier comparison:

0781855A-2184-4ECA-9420-6F92C22CED62.png
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg. Plano, TX
Contributor
:
Plano, Texas, USA
Well, this K&N dynamometer power / torque curves are measured at the wheels of the vehicle and not the flywheel. The engine's power is usually reduced by 25%-45% depending on situations.

thats right, but what i mean is that the torque curve is a lot more constant and flat on the k&n dyno than the first calculated one i provided. This could be due to the unit conversion, but it is more likely because the first one only use the peaks to generate a generic curve.
 
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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg. Plano, TX
Contributor
:
Plano, Texas, USA
thats right, but what i mean is that the torque curve is a lot more constant and flat on the k&n dyno than the first calculated one i provided. This could be due to the unit conversion, but itbis more likely because the first one ob’y usethe peaks to generate a generic curve.
Yes, very likely. At least the peak values are matched to the RPM perfectly to the factory specs. And it’s for Euro model 2.5L which has a little different specs too.

The Euro RPM scale on torque curve starts from 1,000 to 9,000 rpm, whereas K&N torque curve starts from 1,500 to 6,500 rpm with much wider scale, which definitely makes K&N torque curve looks flatter.
 
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