Do you really need 93 Octane?

[ewalters]

Just purchased an 07 CX-7 GT with 21k miles. I was shocked to hear about the premium fuel requirement. How closely do I have to stay with that? My previous vehicles (MB C240 and Acura MDX) "required" premium fuel but ran them for years on regular fuel with no problem (My MPG's were a little lower but still good performance). What's been the experience with 07's? Must I run premium all that time or can I run regular with the occassional premium? What's been your experience?

 

[offset_98]

The '07's "require" it, the other years recommend it. I wouldn't take the chance but its your money.

 

[SuperStretch18]

Regular doesn't save any money on this car. Spend the extra coin for the good stuff and you'll get better mileage. Yes, it's necessary and regular can do damage to the engine on a 2007...

 

[erhayes]

Did we forget about mid grade 89? In addition preminum is 91 and that is what is required on 2007s. 93 is considered and sold as super preminum and not required by any year CX7.

 

[offset_98]

Did we forget about mid grade 89? In addition preminum is 91 and that is what is required on 2007s. 93 is considered and sold as super preminum and not required by any year CX7.

Yeah but in places like Chicago, you only get choices of 87, 89 or 93. So you have to go 93.

 

[erhayes]

Or 1/2 + 1/2. I fill with 93 and at ~ 1/2 tank refill with 89. CX7s sold in Alaska run on the highest octane avasailiable which is 90.

 

[singlemalt_18]

Or 1/2 + 1/2. I fill with 93 and at ~ 1/2 tank refill with 89. CX7s sold in Alaska run on the highest octane avasailiable which is 90.

I have done this many times. It makes me feel good to save a buck or two.

Regular doesn't save any money on this car. Spend the extra coin for the good stuff and you'll get better mileage. Yes, it's necessary and regular can do damage to the engine on a 2007...

I agree completely. Although we all like to feel we are saving a few dollars, premium fuel is really not a big deal. It amounts to less than a penny per mile, and that is about $10 per month on 12,000 miles a year.

A Starbucks once a day is much more money down the toilet - literally!

 

[Blendercloud]

Saw this thread and wanted to chime in to affirm what most others are saying.

Yes, you need to stick with a 91 octane minimum. Depending on the state laws and city ordinances in some metro areas you will probably be able to get fuel with 10% ethanol. This will actually increase the octane rating of the fuel slightly. By volume I want to say 91 octane with 10% ethanol ends up being 92.4.

Essentially, 91 octane is should be the minimum you put in your car. However, in cases like Chicago where you cannot get 91, do not skimp and go down to 89. Even on the detuned CX-7 version of this engine that they still will knock significantly if you don't adhere to the required octane levels.

Good luck!

 

[ewalters]

thanks for the posts. I think I will stay with the 91 octane. I don't want to take the chance.

 

[offset_98]

Or 1/2 + 1/2. I fill with 93 and at ~ 1/2 tank refill with 89. CX7s sold in Alaska run on the highest octane avasailiable which is 90.

I assume 90 is probably only in higher altitudes correct? Lower air density creates lower effective compression ratios... That's why in utah and colorado they have like 85 and 84 octane gas and premium set at 90 octane.

 

[Hello]

93 for me..........

 

[mazdaspeedster3]

Leased an 07 CX7 Sport AWD in Nov. 06. Drove the car for 30k miles and never ONCE did we put premium in the car. That was when gas prices were at an all time high and we simply should not have gotten the vehicle but we did and then could not afford the premium fuel. Was a great car, had ZERO problems with it other than uneven tire wear. My wife talks about getting another one sometimes when the 5 goes.

 

[disturbedfan121]

every car from factory in the us has to be run on at least 91 because its the highest available in most areas. majority being CALI cause of CARB.

now if you put aftermarket parts on your car and get tuned for more timing, and for 93 and up then you need to run that one the tune you have..

I only put 93 in my miata, i've tried 91 once and i get a little bit of pinging up top

 

[Blendercloud]

every car from factory in the us has to be run on at least 91 because its the highest available in most areas. majority being CALI cause of CARB.

Just to give you a heads-up, Mazda states 93 octane is required for the Mazdaspeed6 on page 4-2 of the owner's manual. There are also two different versions of the Mazdaspeed6's ECU, Federal and California. Your first statement is incorrect.

Does anyone know if the CX-7 per model year has two simultaneously produced versions of the ECU?

 

[offset_98]

Does anyone know if the CX-7 per model year has two simultaneously produced versions of the ECU?

91 Only nationwide

 

[mazdaspeedster3]

07 Premium was mandatory
08 it was suggested
09 you dont need to run at all...

 

[Hello]

every car from factory in the us has to be run on at least 91 because its the highest available in most areas. majority being CALI cause of CARB.

now if you put aftermarket parts on your car and get tuned for more timing, and for 93 and up then you need to run that one the tune you have..

I only put 93 in my miata, i've tried 91 once and i get a little bit of pinging up top

What carb........

 

[wannabe]

What carb........

Cali Air Resources Board

http://www.arb.ca.gov

 

[8.5MS3]

best way to determine if its required is borrow a DH off any MS3/MS6 owner (i believe 90% of us have one lol) and monitor KR, if your constantly knocking then your octane is too low and you need to step up a grade. easiest way to tell.

 

[neax]

New 2010 CX-7 Turbo owner... The manual states Premium gas but, the 2010 brochure states "Regular unleaded (for maximum performance, premium unleaded is recommended)".

I wonder what that means exactly... How is HP & torque effected? What damage would using Regular cause?

Anyone recommend which oil to use? I'm a long-time user of Mobil-1.