Skyactiv only runs at 80celcius?

[buyingconstant7]

I plugged in my scan tool to see at what temps these Skyactivs run and found its operating temp be to 80celcius. Are these supposed to run this cold? The Tiguan, that the CX-5 replaced, ran at 95c and so does my Jetta TDI. I am familiar with SKyactiv tech and how that the combustion process needs to be as cool as possible in order to prevent knock, so they added a cavity in the piston to sort of control the temps with the direct injection. Is the low temperature, 80c thermostat designed to do that too, or is there another reason? Would there be a problem if it was switched for a 90c thermostat(for whatever reason)?

 

[CX5_Pete]

I noticed this too!

I have the 2.0, and for me it runs at 82* C (181*F) as well. Compared to my other vehicles which kept the water temperature around 88 - 94 *C (190*F - 200*F), it is lower. However, the weird thing is, when I am driving in heavy traffic, the temps get as high as 99*C (211*F). Then the fans turn on and it cools it back down to 94*C in less than 15 seconds. I think this must be some fuel saving technique the water pump uses. Only my old VFR had temperature fluctuations this big.

Another weird thing is the battery voltage. On my other cars, during cruise rpm, the voltage is usually 14+ volts. On the CX-5, it hovers around 13.4-13.8V. It seems like when its colder, the voltage is on the higher end, and vice versa.

 

[CX-5um]

I plugged in my scan tool to see at what temps these Skyactivs run and found its operating temp be to 80celcius. Are these supposed to run this cold? The Tiguan, that the CX-5 replaced, ran at 95c and so does my Jetta TDI. I am familiar with SKyactiv tech and how that the combustion process needs to be as cool as possible in order to prevent knock, so they added a cavity in the piston to sort of control the temps with the direct injection. Is the low temperature, 80c thermostat designed to do that too, or is there another reason? Would there be a problem if it was switched for a 90c thermostat(for whatever reason)?

As a previous owner of a VW CC (same engine as Tiguan), the skyactiv engine runs noticeably cooler than VW's turbo engine. Not sure what switching the thermostat benefits since it could void warranty.

 

[buyingconstant7]

I'd never switch the thermostat, I was just wondering if these engines were that sensitive to heat, that it'd negatively affect running performance if the thermostat was switched for the engine to run at 90-95c. I notice on my TDI, my engine gets noticeably more efficient when the car is running hotter at around 100-105celcius.

 

[Lbear]

I plugged in my scan tool to see at what temps these Skyactivs run and found its operating temp be to 80celcius. Are these supposed to run this cold? The Tiguan, that the CX-5 replaced, ran at 95c and so does my Jetta TDI. I am familiar with SKyactiv tech and how that the combustion process needs to be as cool as possible in order to prevent knock, so they added a cavity in the piston to sort of control the temps with the direct injection. Is the low temperature, 80c thermostat designed to do that too, or is there another reason? Would there be a problem if it was switched for a 90c thermostat(for whatever reason)?

SkyActiv engines MUST run cool in order to prevent detonation due to the 13:1 compression ratio. The engineers knew that running 87 octane they had to do everything they could to keep detonation at bay. This includes engine temps hovering at 175F-180F. I would NOT change the thermostat or you can be looking at detonation issues and serious timing pulls. Maybe even block/head damage.

It has already been proven by data logs that the SkyActiv on 87 octane pulls A LOT of timing, especially when hot outside, towing, loaded with people, climbing grades, etc. One probably loses 20-30HP during these events. The computer goes into safe mode and keeps the timing pulled for a while after sensing possible detonation. That is why when guys run 91-93 octane the data logs show very little to almost no timing pulls by the computer. So the 2.5L engine is at full HP at all times.

 

[Pototoy]

SkyActiv engines MUST run cool in order to prevent detonation due to the 13:1 compression ratio. The engineers knew that running 87 octane they had to do everything they could to keep detonation at bay. This includes engine temps hovering at 175F-180F. I would NOT change the thermostat or you can be looking at detonation issues and serious timing pulls. Maybe even block/head damage.

It has already been proven by data logs that the SkyActiv on 87 octane pulls A LOT of timing, especially when hot outside, towing, loaded with people, climbing grades, etc. One probably loses 20-30HP during these events. The computer goes into safe mode and keeps the timing pulled for a while after sensing possible detonation. That is why when guys run 91-93 octane the data logs show very little to almost no timing pulls by the computer. So the 2.5L engine is at full HP at all times.

hmmmm.

This is why I kept saying 91 octane is better for me. now, I have to go back to 91..

 

[yrwei52]

SkyActiv only runs at 80C?

This is why I kept saying 91 octane is better for me. now, I have to go back to 91..

But you don't need full 184 hp @ 5700 rpm‎ most of time ...

 

[Pototoy]

But you don't need full 184 hp @ 5700 rpm‎ most of time ...

Ahhh, yes I do. lol I'm bitching the hell out of this little 'ute.

 

[CX5_Pete]

SkyActiv engines MUST run cool in order to prevent detonation due to the 13:1 compression ratio. The engineers knew that running 87 octane they had to do everything they could to keep detonation at bay. This includes engine temps hovering at 175F-180F. I would NOT change the thermostat or you can be looking at detonation issues and serious timing pulls. Maybe even block/head damage.

It has already been proven by data logs that the SkyActiv on 87 octane pulls A LOT of timing, especially when hot outside, towing, loaded with people, climbing grades, etc. One probably loses 20-30HP during these events. The computer goes into safe mode and keeps the timing pulled for a while after sensing possible detonation. That is why when guys run 91-93 octane the data logs show very little to almost no timing pulls by the computer. So the 2.5L engine is at full HP at all times.

Where are these data logs?

 

[Lbear]

Where are these data logs?

There is/was a forum member that did logs and tunes on the SkyActiv engines and he posted on numerous threads about it. He had screenshots showing the timing being severely pulled when on 87 octane. The Mazda engineers put in a lot of safety parameters to prevent detonation with 87 octane and 13:1 compression. This results in heavy timing pulls and HP losses.

Do a forum search and you will pull up the thread and posts discussing the data logs and tunes that Mazda did with the SkyActiv

 

[CX5_Pete]

There is/was a forum member that did logs and tunes on the SkyActiv engines and he posted on numerous threads about it. He had screenshots showing the timing being severely pulled when on 87 octane. The Mazda engineers put in a lot of safety parameters to prevent detonation with 87 octane and 13:1 compression. This results in heavy timing pulls and HP losses.

Do a forum search and you will pull up the thread and posts discussing the data logs and tunes that Mazda did with the SkyActiv

Ah TBot101. I saw the data. Doesn't really prove anything. Also hard to say if it was reliable since he is a tuner promoting his own tune. For all we know it could be a timing chart off of one of his modified tunes. Still no proof that running 91 is worth it. I mean the ECU could pull timing on 91 gas as well. If you're climbing a grade and suddenly mash on the throttle, I would expect some timing retard, regardless of 87 or 91.

 

[Unobtanium]

What's the oil temp? My Z06 had oil and coolant temp live read-out, and they quite often had disparity between them for sure.

 

[Unobtanium]

There is/was a forum member that did logs and tunes on the SkyActiv engines and he posted on numerous threads about it. He had screenshots showing the timing being severely pulled when on 87 octane. The Mazda engineers put in a lot of safety parameters to prevent detonation with 87 octane and 13:1 compression. This results in heavy timing pulls and HP losses.

Do a forum search and you will pull up the thread and posts discussing the data logs and tunes that Mazda did with the SkyActiv

I would LOVE to see track numbers on this. Cold pass vs. hotlapped on the 1/4 mile. I am not arguing that timing is pulled or whatever, but I have never *felt* it, and I want real-world quantification of it.

 

[Lbear]

Ah TBot101. I saw the data. Doesn't really prove anything. Also hard to say if it was reliable since he is a tuner promoting his own tune. For all we know it could be a timing chart off of one of his modified tunes.

Actually it does prove a lot of things. Of course you slam the guy without any valid proof. Attack the messenger and then discredit his data without proof.

Still no proof that running 91 is worth it. I mean the ECU could pull timing on 91 gas as well. If you're climbing a grade and suddenly mash on the throttle, I would expect some timing retard, regardless of 87 or 91.

The data proved that higher octane fuel will be beneficial on a 13:1 compression engine. It won't ever see over 185HP but running 87 octane under certain conditions will definitely see lower than 185HP levels due to timing retard.

 

[Chris_Top_Her]

I would LOVE to see track numbers on this. Cold pass vs. hotlapped on the 1/4 mile. I am not arguing that timing is pulled or whatever, but I have never *felt* it, and I want real-world quantification of it.

All you need is the torque app (free for android), and https://www.ebay.com (commissions earned)$12 obd2 adapter to log timing max and low. I wouldn't timing log until the engine is warmed and stop before shutting off. If you don't have an android phone, any androd device with Bluetooth (old phone etc) will work. If you need an android device, you can get something like this http://www.gearbest.com/cell-phones/pp_96129.html or less if you look around gearbest or check aliexpress.

Then you can see what your maximum timing advance is from 87, in you environment/driving habit. But it goes without saying if your ECU is pulling timing for some reason; engine load, environment factors, engine temp etc, then your going to experience a power loss greater than the same situation with a higher octane.

 

[Chris_Top_Her]

of course I just bought something from gearbest that I saw, but it was only $10

 

[Unobtanium]

All you need is the torque app (free for android), and https://www.ebay.com (commissions earned)$12 obd2 adapter to log timing max and low. I wouldn't timing log until the engine is warmed and stop before shutting off. If you don't have an android phone, any androd device with Bluetooth (old phone etc) will work. If you need an android device, you can get something like this http://www.gearbest.com/cell-phones/pp_96129.html or less if you look around gearbest or check aliexpress.

Then you can see what your maximum timing advance is from 87, in you environment/driving habit. But it goes without saying if your ECU is pulling timing for some reason; engine load, environment factors, engine temp etc, then your going to experience a power loss greater than the same situation with a higher octane.

I have a droid. Thinking of downloading a g-force type accelerometer. I remember last time I did, it was SPOT ON for my G20 vs. magazine 0-60 times.

 

[yrwei52]

SkyActiv only runs at 80C?

The data proved that higher octane fuel will be beneficial on a 13:1 compression engine. It won't ever see over 185HP but running 87 octane under certain conditions will definitely see lower than 185HP levels due to timing retard.

I agree that there're certain severe conditions like you mentioned earlier that timing retard would be happening more if the 87-octane regular gas instead of 93-octane premium gas is used. This makes sense in theory. But this won't be happening too often to average CX-5 owners under normal use.

BTW, the maximum horsepower for SkyActiv-G 2.5L in the US is 184 hp @ 5700 rpm; not 185 hp.

 

[yrwei52]

SkyActiv only runs at 80C?

All you need is the torque app (free for android), and https://www.ebay.com (commissions earned)$12 obd2 adapter to log timing max and low. I wouldn't timing log until the engine is warmed and stop before shutting off.

It'd be nice if you can do some sort of test on this since you're good at it with all the equipments to settle this for us all. But you may not have factory ECU map anymore with your turbo mod so may be Unobtanium is willing to give it a try?

 

[davesxx01]

Actually it does prove a lot of things. Of course you slam the guy without any valid proof. Attack the messenger and then discredit his data without proof.



The data proved that higher octane fuel will be beneficial on a 13:1 compression engine. It won't ever see over 185HP but running 87 octane under certain conditions will definitely see lower than 185HP levels due to timing retard.

I've been data logging my car and am tuning for 89 octane. As stated, these ecu's will always pull timing based on all kinds of different things. It is totally true that there is more "pull" of timing on 87 octane than 91.
Sadly, all the datalogs in the world will not prove anything to some people.