Mazda 3 engine in CX5

[NL_CX5]

Hi all, hoping someone can answer the question.

I bought a used and damaged cx5 - nothing major - but turns out the vehicle was rolled onto its side and the engine is now toast. Company I bought it from has agreed to replace the engine, however they do not have a cx5 engine.

My vehicle is 2013 gs awd 2.0l gas. Replacement engine they are going to use is 2013 mazda 3 gs 2.0l skyactiv, which is what they have in stock.

According to my local mazda dealer, following is the exact same part # on the 2 engines
1. cylinder head
2. empty block
3. exhaust gasket
4. fuel injection system
5. electrical
6. horsepower is the same

here is what is different
1. internal block parts
2. the 3 engine lacks the counterbalance shaft
3. torque is slightly lower in 3 engine, and the curve is also lower
4. base pan is different, but can be swapped over
5. air intake is different but can be swapped over
6. compression in the 3 is 12:1 vs 13:1 in cx5
7. 4-2-1 exhaust in the cx5 but not the 3

Part Recyclers say the 3 engine is a family match for the cx5, so I've no doubt it will fit. The lower torque is a small concern to me given the complaints about the lack of zoom zoom in the 2.0l cx5, although I really just need a vehicle to get me from A to B, so it's not really an issue.

Anyone have any comments about potential issues, either short term or longer term?

 

[erhayes]

You confuse me. They are going to give you a 2.0L SkyActive but, below you say what is different that parts are not SkyActive. Please clarify..

 

[NL_CX5]

You confuse me. They are going to give you a 2.0L SkyActive but, below you say what is different that parts are not SkyActive. Please clarify..

Sorry if I've confused you.

Both engines are skyactiv, but the 2013 mazda 3 is not the exact engine as in the cx5. Differences are as noted above.

 

[erhayes]

I thought SkyActiv engines only can with compression ratios of 13:1 USA or 14:1 Europe. In addition: if you remove the SkyActive parts (what is different), then it is NOT a SkyActive engine. At least this is my take on what you have shared. Ed

 

[NL_CX5]

If you look at this link http://www.mazda.ca/MciWeb/displayPage.action?pageParameter=modelsSpecs&vehicleCode=M3H it shows the GS model is skyactiv with 12:1 compression, and so I expect the US models with Skyactiv are the same.

 

[paris1]

SkyActiv 2.0 was introduced in 2012 Mazda 3 with 12:1 CR and old style exhaust manifold because engineers couldn't fit the 4-2-1 header into the old body. Call it SkyActiv-lite. All that changed in 2014 with the full SkyActiv technology suite in the current 3.

 

[GAXIBM]

NL I read that none of the 2.0 engines have the balance shaft so some of the items in the comparison are from a 2.5 which has the balance shaft. If you compare a true 2.0 CX-5 to a 2.0 3 some of the differences may disappear. If the compression ratio is lower you will probably be able to run lower octane/less expensive fuel but you will give up slight power. What is the comparison in power/torque?

 

[NL_CX5]

Power for both are the same at 155 @ 6,000 rpm. Torque for the 3 is 148 @ 4,100 rpm, while the cx5 torque is 150@4,100 rpm. Both run on regular unleaded.

 

[piotrek91]

The difference in peak torque between the two engines is not much (2lb-ft) but the torque curve of the 3 engine (12:1) is not nearly as flat or high as that of the 13:1 CX-5 engine.
Besides the obvious impact on performance you might find that the lack of torque at 3000 RPM causes issues with the shift points of the transmission. You might find the car shifting into a higher gear too early for the lower torque of the 3 engine.. you should be able to get around this by using the manual mode more.
The other issue I see is that you'll probably need to use the ECU from the 3 engine.. which could have trouble talking to the AWD system in your car.

 

[GAXIBM]

The difference in the torque curve is likely due to the 4-2-1 manifold in the CX-5 and not available in the 3 until the recent redesign of the body. I think you should use the ECU from the CX-5 if possible, but I am not sure the effect of the lower compression ratio...

 

[NL_CX5]

That graph (picture) is certainly worth more than a thousand words - awesome visuals. I saw an article a while back that talked about this difference but couldn't find it yesterday. Just to clarify, that 3 curve is from the 2013 model without the 4-2-1 exhaust?

I'll have to see what they say about the ECU. I want something that works and works well and your findings give me reason to question using that engine. They've given me the option to take a $1000 and then I buy my own engine and have it installed, but I will have to get the engine shipped to an island as there is not cx5 engine here. It will probably cost me out of pocket another $1000-$2000 extra for the engine and to have it installed. Hard to justify, but maybe it's a case of pay me now or pay me later with other issues.

Thanks for the reply.

 

[NL_CX5]

Both yours and piotrek91 comments on torque made me research affect on torque of exhaust system. i wasn't aware that the exhaust system can affect the torque curve, so I hope that the majority of this difference can be accounted for by the 4-2-1 exhaust system in the cx5. I've also read that an increase in compression ratio affects torque as well, and a quick calculation tells me that the 2 lbs difference in peak is probably the result of the 13:1 CR vs 12:1. Hopefully most of the curve difference is the exhaust, and I can use the cx5 ECU to handle the AWD correctly.

 

[CodyZoom]

Thank you for sharing the graphic - very interesting.

 

[erhayes]

Where is the reference for the plot? To me it looks very questionable with the sharp angles as to very few data points. Ed

 

[NL_CX5]

Got it back today. Can't really compare before and after because the engine appeared fine when I first bought it, but after towing it to be inspected and then starting to drive home, it became apparent the engine was gone. The company I bought it from provided the engine and labour, so not a whole lot to complain about.

Seems to run fine now. I had it on the highway. I know it's only a 2.0lt and there are complaints anyway of that engine being a little low on power, and my previous vehicle was a V6, so really hard to say if it was a good swap or not.

 

[V8toilet]

Got it back today. Can't really compare before and after because the engine appeared fine when I first bought it, but after towing it to be inspected and then starting to drive home, it became apparent the engine was gone. The company I bought it from provided the engine and labour, so not a whole lot to complain about.

Seems to run fine now. I had it on the highway. I know it's only a 2.0lt and there are complaints anyway of that engine being a little low on power, and my previous vehicle was a V6, so really hard to say if it was a good swap or not.

So you have the 3 engine in your CX5 with 12-1 compression? Couldn’t they have just rebuilt or fixed the original motor?

 

[Chris_Top_Her]

no speed motor swap?

 

[NL_CX5]

So you have the 3 engine in your CX5 with 12-1 compression? Couldnt they have just rebuilt or fixed the original motor?

No warranty as it was in an accident. The company I bought the vehicle from fixed it, and to rebuild the original would have been a lot more money. I had nothing in writing saying they would fix something major, so this was the best they would do and I wasn't in a position to pay the difference (which would have been substantial).

 

[NL_CX5]

As in a speed turbo?

 

[Bladecutter]

Seems to run fine now. I had it on the highway. I know it's only a 2.0lt and there are complaints anyway of that engine being a little low on power, and my previous vehicle was a V6, so really hard to say if it was a good swap or not.

If you really want to know, go to a Mazda dealer, and test drive a brand new CX-5 in the same trim level as the one you currently own.
That will answer any questions that you have about the power difference.

BC.