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Discussion Starter · #1 ·
I was reading that when you install a short intake on the 1.4, it can cause the car to sputter sometimes when you first start it up because it confuses the computer. How legit is this? Mine does this, sometimes barely noticeable and other times pretty rough. It runs and starts fine after this as long as the engine is warm. If it sits and cools down, it starts rough. Im hoping the tune fixes this. 馃枛
 

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You have to have the tuner rescale your MAF. He will send you a tune that disables your O2 sensor so he can log the fueling error, then scale it, and apply it to your new tune. If your lucky he will scale your virtual volumetric efficiency table too. Totally normal when you mess with the intake though.
 

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Discussion Starter · #4 ·
You have to have the tuner rescale your MAF. He will send you a tune that disables your O2 sensor so he can log the fueling error, then scale it, and apply it to your new tune. If your lucky he will scale your virtual volumetric efficiency table too. Totally normal when you mess with the intake though.
Are you sure they turn the O2 off? I thought they dont do that anymore do to the new EPA rules. I wish they would because mines on from a catless DP. 馃ぃ
 

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Yeah, to tune the MAF you temporarily disable the "upstream" narrow band O2 sensor and the dynamic air calculation used from the virtual volumetric efficiency table (ECU's air calculator for fueling). That's the first step to scaling the MAF. It allows you to disable the closed loop capability, then you can log what the fueling is doing based off of the MAF sensor table alone. When your done scaling, you re-enable the O2 for the babysitter ECU to adjust for air density changes.

So as an example, if the ECU is commanding 1.00 位 (Lambda air/fuel stoich), but let's say your MAF is off at a particular airflow, so your wide band will read like say 1.05 位 (meaning 5% lean) because you have disabled the O2 from correcting the mixture. Now you can just go into your tune and correct your MAF curve at that exact airflow. By lowering it's understanding of the airflow for that frequency, your MAF will now command the exact desired fuel based off it's now correct airflow calculation. So technically if you have a perfectly tuned MAF, there is no need for an O2 sensor on your vehicle. Obviously this is unobtainable with elevation and temperature changes, but I'm just trying to make a point you know?
 

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2015 Cruze 1.4L engine 6 speed AT
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Keep in mind this intake was installed AFTER a turbo upgrade and after a ported intake and AFTER a tune. Just to be clear, ZZP makes intakes (and other products) just as good or better than anyone. I have been buying their stuff for about 15 years. (y)

As always I try to bring some sanity to the people. There WAS a day when many car manufactures mostly ignored intake design and they WERE pretty bad. But this hasn't been the case for a decade or longer, and is certainly not the case for our cars.

But you know what I really bothers me. When a car company like GM spends hundreds of thousands of dollars on designing an intake that provides cold, highly filtered, precisely controlled air flow to my cars engine. It also bothers how the intake can support at least an extra 50 HP over stock and still not restrict the engine. Not to mention when I'm driving my engine at redline, I need that aftermarket intake for the extra 5 HP to run my air conditioning so when my engine blows up I'll stay comfortable until the tow truck arrives.

Stock intakes are great for fuel efficiency and keeping the car quiet, but you know what they really need is to be more open. You know when you hit standing water on the interstate or when the local streets get a bit flooded, I want to pull some really cold water into my intake. The stock intake makes this really hard, basically impossible to do that.

I also think that cars should run really badly and barely be able to idle. Look at the the most iconic motorcycle brand in America, selling machines that can barely run. I want a car like that.:love:

4:55 "They do absolutely nothing below 4000 RPM"

"Low single digit gains until about 5200 RPM"

 
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