Mazda CX‌-90 Forum banner

I6 differences?

4201 Views 46 Replies 14 Participants Last post by  NyquistRate
So there was an article posted by TFL saying the 2 - I6 variants are mechanically identical and the hp/tq rating difference is only due to premium vs regular fuel.

Any way to confirm this as it seems hard to believe. I would assume there are pressure differences between the turbos or something in the computer programming.

I know someone had access to the parts diagrams. Are the turbo units the same part numbers between S and non-S variants?
  • Like
Reactions: 3
1 - 2 of 47 Posts
mazda is a small company and it doesn't make sense to make two different engine. it's most likely just different ecu engine tuning.

higher octane gas will allow you to run more boost and timing in the upper rpms, which is how the higher trim yields more hp.

in other words, the low trim cx90 is running a detuned engine.
  • Like
Reactions: 1
Agreed that it isn't different engine hardware and likely tuning differences. Would that also allow them to increase the boost pressure or would they use a different turbo? If the internals are the same then the non-S engine and transmission is being stressed less in terms of boost pressure and hp/tq.

The Mazda usa specs page has a different description for the electric motor on the S and non-S model but the hp and torque specs are the same so I don't think that is the difference.
the engine ecu controls the amount of boost requested. Most likely same turbo. Most of the HP is probably from running more advanced timing in the upper RPMs. Maybe 1-2 psi more. Modern turbo chargers aren’t efficient in the upper rpms.

notice the top trim requires premium fuel. That’s because the ecu is running more boost and timing and you need the higher octane to reduce knock. More knock means more power being pulled.
  • Like
Reactions: 1
1 - 2 of 47 Posts
Top