2008 CX-7 able to run 87 octane

Adammazda06

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Not sure if this has been posted, but I just found out today that the 2008 Mazda CX-7 has been recalibrated to run regular 87 octane. they recommend premium, but running regular will be ok for '08. This info was in a new Mazda Fuel news letter magazine we get at the dealership.
 
Yes it's OK for 08's, but I still wouldn't recommend buying the CX-7 because of it, you get poor performance on 87.
 
Yes it's OK for 08's, but I still wouldn't recommend buying the CX-7 because of it, you get poor performance on 87.

oh i 100% agree and i wouldnt run anything but 93 in my speed3, but it is a wonderful new selling point. i am curious to know exactly what they did to the 2008. any ideas?
 
The changes may be several things i.e. slightly more timing set back, changing the variable intake valve timing, riching up the fuel mixture during acceleration and and and. The compression ratio is listed as the same as the 07. We can only guess at this point. IS IT IN MAZDA OWNERS MANUAL THAT 08 CAN USE 87 OCTANE?? I thought someone mentioned the wording was changed from 91 octane REQUIRED TO 91 OCTANE PREFERRED. Let us know what is the written word from Mazda!!
 
2007 manual, page 4-2
Your Mazda will perform best with fuel listed in the table.
Fuel Octane Rating*(Anti-knock index)
Premium unleaded fuel 91 [ (R+M)/2 method] or above (96 RON or above)
* U.S. federal law requires that octane ratings be posted on gasoline station pumps.
This vehicle is designed for and requires use of premium unleaded fuel. If 91 octane fuel [
(R+M)/2 method] (96RON) is not available, gasoline as low as 87 octane [ (R+M)/2
method] (91RON) can be used temporarily for emergency purposes. Use of gasoline lower
than 91 octane [ (R+M)/2 method] (96RON) can decrease performance and deteriorate shift
quality during its use. Refueling the vehicle with the correct octane fuel a couple of times
will restore vehicle performance and shift quality.
-----------------------------------------------------
And the 2008 manual also page 4-2
Your Mazda will perform best with fuel listed in the table.
Fuel Octane Rating*(Anti-knock index)
Premium unleaded fuel 91 [ (R+M)/2 method] (96 RON) recommended
* U.S. federal law requires that octane ratings be posted on gasoline station pumps.
This vehicle is designed to use 91 [ (R+M)/2 method] (96RON) or higher gasoline for best
performance. If 91 [ (R+M)/2 method] (96RON) is not available, 87[ (R+M)/2 method]
(91RON) gasoline can be used. Use of gasoline lower than 91 [ (R+M)/2 method]
(96RON) can decrease performance, deteriorate shift quality and cause engine knocking
during its use.
 
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I got it from a Mazda rep that the PCM has been reprogrammed and a couple other things have been changed. When running 87 octane there is little or no difference until you pass 5000 RPM at which point there is a slight drop in power. So depending on how you drive it may not be an issue.
 
I got it from a Mazda rep that the PCM has been reprogrammed and a couple other things have been changed. When running 87 octane there is little or no difference until you pass 5000 RPM at which point there is a slight drop in power. So depending on how you drive it may not be an issue.

Well the power peak isn't much past 5000 RPM... I would think that running 87 octane in a high boost, relatively high compression engine would result in a more noticeable drop in power sooner than that.
 
The next obvious question is whether Mazda can do this tuning for the '07 owners.

No, they cannot. Truthfully, it wouldn't matter anyway. Mazda still recommends premium for all CX-7's, if you are looking to maximize performance. I for one am, and will continue to use the good stuff! I agree with AWMustang and think that performance would be impacted much more heavily than stated in this thread...
 
From the written information above. Fuel lower than 91 octane can cause lower performance, poor shift quality and engine knocking (detonation). All that sounds like a very poor trade-off to me for at ~ $2.50 per week. As for the verbal comments, it's all hear-say and if you don't believe it, try to use that excuse for warranty work.
 
It's not so much that its a Mazda, its that this particular Mazda has a turbocharger, and nearly every turbo charged engine needs high octane gas to run its best. Running on 87, you will take a performance hit, it's whats best for the engine(vitally). And if you get on it your car will run like a CR-V with no power.
 
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My feelings are: If money (`$2.50) per week is going to cause issues then I would still use 91 octane but, try to drive fewer miles, give up one pack of smokes or a 6 pack or something. If all the above is not doable then you've bought or plan on buying the wrong car. JMO. Ed
 

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