Knock After Stock to FM Intercooler Swap

[bdeliman]

I have swapped from a stock intercooler to a PT&E front mount, and I am getting a significant amount of knock in 2nd and 3rd gear. I was running 27-28 degrees advanced with the stock intercooler, and had to reduce to 20-21
degrees to reduce the knock. I have swapped back to the stock IC to see if the knock was still present, but it was gone. Then I reinstalled the front mount, and the knock reappeared. I have made sure the the mounting and piping is firm and not hitting anything, so as not to create any contact that might trigger the knock sensor. Any help would be appreciated.

 

[noslo6]

Well, I had a similar situation when I went to my front mount. I believe that you are seeing a significant increase in airflow that is causing a lean condition. That was my take anyway. Add a little fuel or more alcohol and see if it goes away.