MPG pre and post tune

[aviator79]

I am in the market to get this for my CX-7. Currently the wife drives it and mostly driving slow she gets about 14mpg. That is about 16.8 L/100km.
If she got 15mpg that would be about 15.68 L/100km.

So what are you all getting before and after? One post by Sassimac which said his went form ~15L/100km to ~13.6L/100km which equates to going from 15.68 MPG to 17.3 MPG.

Another post he mentions getting 9.8L/100km which is 24 MPG which is insane.

I get about 20mpg in my MS6 so I find it ridiculous that the CX-7 gets such bad mileage/kilometerage.

Hope to compile more info on this, but it looks like I may just have to purchase first and see what happens. Please post more info on what mileage you are getting.

[Sassimac]

The CX7 has always had very bad economy. Mazda's factory figures have been well commented on many times in the past as "How the hell did you get that..???"

I am extremely happy to be getting almost 1 1/2 litre better per 100km now. As I drive very short metro distances (~12km), my economy will never be good. Highway driving will reduce that substantially, but I rarely do that kind of driving.

Any gain, is a good gain. Especially with fuel getting closer to $1.80 a litre during peak cycles.

[lildisco]

My 2008 CX7 AWD GT fluctuated between 18mpg and 22mpg, with the occasional 16mpg (wife driving) and occasional 24mpg while traveling mostly highway. Wanted something that can deliver better drive ability, more hp/tq & better fuel economy (most important). So far, using Sassimac's tune (thanks BTW), i've gained 1.17mpg from my average of 20.3. Got 21.2mpg on my last fillup with roughly 100 miles on the stock tune & roughly 150 using Sassimac's tune. I wasn't exactly easy on the car either. Very interested to see what's going to happen. I know squat about tuning so having someone else tune was incredibly helpful. VERY interested on how the rest of my 'testing' pans out! Thanks Steve and Sassimac!

[Sassimac]

Hi There...

I am glad the file has worked well for you, and your economy is better than before. Please tell me how you find the car to drive with my tune.

Cheers..!!!

[lildisco]

So far so good. Its much improved over stock. It feels more alive all the way around better on top of better fuel economy. This is exactly how I want the car to drive. Power when you need it and fuel economy when you don't. I'll see with, the holiday weekend coming up, if I can drive the car more. Also heard a rumor of an economy tune, very interested in that.

[lildisco]

I have noticed some knock with your tune Wayne. Is there anything to be done about it? I noticed it while just cruising about 55mph, not in boost. According to my logs, it also done it under WOT throttle too.

[Sassimac]

Hello There...

The car knocks a lot under the stock tune. And that has never caused an issue.

The theory I work with is to give the car as much timing as it can use until it knocks. And at that point it will retard. This is what I have done at the low load points for cruise RPM's. If you see knock at WOT, just pull the timing at the load/rpm point. I had this tune run up on a dyno, and we never worried about the small amount of knock that appeared.

I will have a look at the logs when I hop on my tuning laptop.

Cheers..!!!!

[lildisco]

awesome. I know very little about tuning, but it looks like @ WOT it's happening about 4,500 rpms. I'll wait for your input before i mess with anything. Looks like the most knock i see @ WOT IS .7 degrees. But cruising i get 5.63 degrees. Anything to worry about?

[Sassimac]

Personally........

WOT knock of 0.7 is no issue.

Cruise knock can be ignored too. I have seen 6+ knock with the stock tune.

[Sassimac]

Hello There...

I just had a quick look at your logs, and I would be happy with them. Boost is not insane, fueling looks OK and the small amount of knock is not what I personally would worry about.