I just called Cobb and they said that the Ztube should not change your A/F ratio that much. Don't have to worry about detination. They said to watch the live data screen with A/F ratio and make sure that it stays between mid 12 and high 13. I also asked them about a plenum spacer and they said you would have to get a pro tune because it would lean it out, but they said that a plenum spacer wouldn't do much for the car anyway. Good news for me cuz I just bought a ztube on ebay!
Sorry, I'm calling BS on this.
they said it wouldn't do much yet they are saying that it will run lean if you install one??? well which is it? Is it allowing more air in causing it to go lean or is it not "helping much"?
I just called Cobb and they said that the Ztube should not change your A/F ratio that much. Don't have to worry about detination. They said to watch the live data screen with A/F ratio and make sure that it stays between mid 12 and high 13. I also asked them about a plenum spacer and they said you would have to get a pro tune because it would lean it out, but they said that a plenum spacer wouldn't do much for the car anyway. Good news for me cuz I just bought a ztube on ebay!
The whole point of the plenums/spacers on the earlier model G's/Z's is to get more air to the front two cylinders. As far as leaning out those cylinders, yes the plenums/spacers should do that. No it won't be extreme enough to cause detonation. No a plenum spacer doesn't do much for the car.
You have to realize that the Cobb guys are really working with some serious power mods all the time, so comparitively speaking 10-15 whp is nothing. Yes they do recommend a protune because it would be car specific, but your ECU should be able to adjust for these changes, but you are at the mercy of your ECU.
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Now I'm just laid bad - G35Princess
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I can't remember exactly what he said now but he said something like since the MAF is in front of the ztube it should be able to compensate for the little bit more of air that is being let in. Keep in mind the z tube is stock on the 350z and they do the same motors. Putting on the z tube will not change the A/F so drastrically that the motor will run bad. He said that if the car runs to lean it will lose power and you should be able to fell that. He also said to get a feel for how the car runs be4 and after the mod to tell if its hurting the motor.
they said it wouldn't do much yet they are saying that it will run lean if you install one??? well which is it? Is it allowing more air in causing it to go lean or is it not "helping much"?
The MAF sensor is a heated piece of metal in the intake, the ECU measure the amount of energy needed to keep the metal at temp - that gives it airflow.
The O2 sensor is in the exhaust, it reports if the exhaust is rich or lean. The ECU adjust the injectors based on this information
The predetonation/anti-knock sensor tells the ECU to retards the timing if it picks up a problem.
The MAP is a starting point - the ECU makes a 100 adjustments a second, the car won't run lean.
Been drivin around now for a while with the z tube an accessport an car has been running great. Sounds a lot different with the ztube, whistle below 3 an growl above 3
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