Take a look at my log....

[Slostjoe]

I'm posting this here as I am getting ready to take the car to get it tuned, I'm having issues with the car breaking up horribly and upper RPMs which I made another thread about, I'm going to post a log and see if it looks right to you guys

The person that is tuning my car currently via email tune says that it is normal, I would just like a second opinion before spending 500$ on yet another tune.

The lines along the bottom are fuel trims, notice how they are basically flat up until 7500 rpm then it starts dumping fuel due to it being lean which is where the car basically falls on its face.

Thanks!

 

[mhyjek]

To get a look at the datalog your better off posting a csv. file.

 

[cruizinmax]

Having ridden in this car while it is happening I thought I would share my observations. It actually feels like valve float to me. In the data log you can see the mass air sensor flow drastically drops off at exactly 7500 rpm. Could anyone else shed some light on this? Is it normal for cars with the boss intake manifold to have such a sudden drop in airflow like this?

The only cars documented that I found suffering from valve float were turbo cars from excessive back pressure. Btw this car does still have stock mufflers.