Engine confusion

[mtnbob]

The 2.5 in the CX-7 is the same engine as in the 3 hatch and the 6, right? If so why 3 different hp ratings? And why detune it when put in a heavier vehicle? In the 6, it has 3 more hp than the 3, in the cx-7, 6 less than the 3. Not huge differences, but I'm betting that nearly all cx-7 owners would agree that the cx-7 could use another 9 hp or more. Anyone know what the differences are and why Mazda wouldn't make it simplier and have just one version instead of 3 nearly identical, but obviously different, versions?

 

[AL1EN]

Its a 2.3 turbo not a 2.5 turbo. and i belive the 2.5 is in the new 2010 and they come non turbo. but from what i was told the detune was to save money. Correct me if im wrong.

 

[erhayes]

The 2.5 in NOT turbocharged. The different tuning are used to maximize performance relative to the cars weight. You have been mislead into looking at the HP instead of the engine torque and at what rpm the max torque occurs at.

 

[mtnbob]

Good point, but where might one find the comparative torque graphs? Company sites (any one) are notoriously bad about giving out any really useful info.
Mazda site doesn't even acknowledge the existence of the cx-5, for example.

 

[erhayes]

I have seen the CX7 turbo torque vs rpm curve but, not the 2.5 litre engines. I'm sure it is somewhere but, remember that the torques vs rpm at part throttles is possibly more interesting than the WOT curve. Maybe someone will point us in the direction of the torque curves for the 2.5L engine.

 

[mtnbob]

Yeah, I'm more interested in power down where I drive - 2-3,000 rpm.