Hey guys, right now I'm getting something like 11MPG local and 20MPG highway and I'm really not driving hard at all... would the Stage 1 93 OCT COBB map help get my MPG up? From what I've read the low MPG is due to the stock tune running extremely rich...does anyone know how rich the stock tune really is? and how does the stock AFR compare to the cobb stage 1 map?

Also would I really need a boost gauge if I just use the cobb stage 1 map?

I've heard everyone say the stock tune is terrible, can anyone explain to me what else is bad about the stock tune?

thanks

 

The stock tune runs very very rich. Like in the 9:1 AFRs at WOT.

Any tune including the Cobb one will lean your car out enough for you to notice a gain in MPG given the same driving style.

 

You shouldn't need a boost gauge for Stg I or Stg II with an AP. Some, myself included, like to have a boost gauge around just to know what the car is up to. That being said the AP will read boost and log boost allowing you to keep an eye on the car if you are curious.

Thanks,
Rob

 

Rob,

Does the AP read air/fuel ratios and log them? Would it be necessary then to have a wideband like the UEGO? Thanks.

Dave

 

You will get better MPG at WOT vs stock, but I noticed that when cruising the MPG is about the same because your car runs in closed loop at cruise and a closed loop you get 14.7 AFR before and after a tune, for better MPG 15.2 AFR would be best....but you cant tune closed loop unless you tune to run open loop cruising. Bryan(razorlab) could explain this better as he just explained this to me too. haha.

 

The AP will only log parameters that the stock ECU can see. Since the Evo does not use a wideband, the parameter would not be available. Having said that, an external sensor, like the UEGO, would work well. At this time, it(UEGO signal) can not be sent to the AP to be recorded in the log.

Hope this helps a little.

John

 

To add on to what John said, it is not necessary to have a wideband unless you are tuning the vehicle yourself.

Thanks,

 

^So John i just got my AP and when I have it on the Boost Gauge setting it is only reading up to 18PSI am i just on the wrong setting or what

Thanks

 

No, you are most likely setup ok. Currently there is a cap on the factory boost monitor of 18.xxpsi. We are currently working to make it read higher.

Thanks,

 

The ZChip has extended closed loop operation which will notable improve gas mileage as well as wide open throttle application.

 

Im not sure how much it will raise your MPG due to the addiction of always having your foot in it, but I love my Accessport, and all the options it comes with. You also cant beat how easy it is just to plug in and flash the ECU.

 

you probably can't change your AFR for COBB for cruising ..

Maybe later .. but I won't release any more info on the ECU until the software is released .. but you can adjust your cruise AFR on the ECUFlash ..

 

the Cobb Accessport also has the fuel economy map.

 

^ How is it a fuel economy map? Less power? Because at cruse the AFR is 14.7 no matter what they do as the high octane maps...the ECU switches to closed-loop on a stock tune at cruise, which then requests 14.7 until back in open-loop. Or are they making the car run in open-loop cruise? That's the only way I can think of them doing it right now to get a 15.2 AFR at cruise, which is the best AFR for MPG...and that's the only way you are really gonna get MPG without robbing power at WOT. But open-loop cruise seems more than a Cobb OTS map would do....

 

There are several ways to change a tune for better fuel economy whether is be higher AFRs at cruse, changing closed loop crossover points, MIVEC changes, etc. Changing the cruise AFR can be a potential problem for the cats and or the motor if high quality fuel is not used. Some of the European cars have a cycle switching between lean burn and slightly rich for better fuel economy while keeping the cats healthy. The ECU will not allow a lean burn if the fuel is too low of quality. Blind changing of the cruise AFR could cause damage to the motor.

Remember an engine is an air pump. Increase it's ability to inhale/exhale, there is some efficiency.

There are other items that can help efficiency such as un-sprung and sprung weight. What size and type of tires being run.

Then the most important way to increase fuel efficiency, the driver.

Thanks,
Rob