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Discussion Starter #1
I know everyone is all about making the FiST a track car. I myself think it has plenty for a DD. I'm wanting to get as much efficiency out of it as I can. My sonic was getting 40mpg+ mix driving.
As far as I know intake and exhaust do little for HP/TQ. But how does it affect the mpg. Better airflow in out should make the engine run more efficiently producing better mpg right? The tune is obviously going to help in economy map. Added performance is a bonus. Thoughts?
 

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It's all in the way you drive it. More power means easier to get around on less fuel, right? But then you have to have the discipline to keep out of the throttle.

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Discussion Starter #3 (Edited)
Well aware my friend. I generally shift about 2k rpms. Unless I'm in some twisties and I can't help myself lol.
I'm just curious if there are any mods that help more to the efficiency side than power. Or is it make her fast n keep my foot off the gas?
 

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A tune can lower the boost pressure so you aren't chugging extra gas every time you run it over 2k, but you can get the same results by just being easy on the throttle. It's a helpful cheat, though, and one that's preloaded on the Accessport.

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A tune can lower the boost pressure so you aren't chugging extra gas every time you run it over 2k, but you can get the same results by just being easy on the throttle. It's a helpful cheat, though, and one that's preloaded on the Accessport.

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Ah. I was wondering if an AP would help with fuel mileage or not... But I guess only when you tell it to!
 

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I've been running different grades of gas to see if there is a difference in mileage based on that. I'm only a few tanks in, but I've been tracking it since I got the car. Also, I just picked up a used AccessPort, gets here friday. We'll see if I can keep my foot out of it to see if it makes an MPG difference. So far my averages (per tank, according to the car) have all been at least 31mpg, with a high of 35mpg. This will be my first "performance" mod.
 

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Discussion Starter #10
I've been going back and forth between Cobb Stg 1 and Mountune MP215, leaning towards the latter for warranty sake. Since I've gotten her broke in I'm getting +/- 37mpg if I keep my foot light staying out of boost using 93 shell. I've seen as low as 29 romping on her all week. Interested to see where you end up. GL with it, hope it performs for you and looking forward to the results
 

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just a quick update, the first couple of tanks bumped up my mpg up to 37-38, but they've gone down to 31-32 since then. Not sure if it's because of different trips that were taken during that time or the tuner. what i've noticed overall is that i can get better mileage on backroads going between 40-60 mph than i can just cruising on the highway at 65mph. The Cobb tune has an economy mode also, i'm going to try playing around with that, too. You can switch between slots (performance and economy) on the fly, so maybe i'll try economy to get up to speed and performance once cruising, and vice versa to see what that does.
 
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