Knocking up top?

[screwdgie]

I just installed some 550's and an afc neo. At 16 psi on a 14b, no matter what i set the afc at I start getting really bad knock right around 5000 rpms. I am also seeing up to 3200 Hz of airflow. Is it just me or does that sound really high?

 

[JayRolla]

Yea its high. You may have a boost leak causing the turbo to work overtime. Also if you on a stock fuel pump that is why you are knocking. Rewire the pump or get a walboro and that should fix your problem.

Ohh and BOOST LEAK TEST

 

[screwdgie]

Ive already done a boost leak test and found nothing, even had DEVO tuning do one, and they found nothing. I swapped in 550s, afc and a 2g mas, and its all good now. I think i was just overrunning the stock one. With the 2g mas on 19 psi, Im seeing about 1500 Hz now. Oh and Ive already got a 190 pump