[kuzdu]

got this installed this weekend on the G42, had it on my F22 before and i noticed a couple of things. i have my exhaust valve open all the time and after the catless dp i noticed the shifts are more pronounced, you can feel them in the floor, i am also stage 3 xhp. also droning is a bit louder when cruising around. anyone have this same feedback with their catless install?

[mike@x-ph.com]

You should not have a noticeable drone with the stock exhaust unless the downpipe does not fit flush and its hitting other components.

[Rdurty2]

It’s because you have your exhaust valve open 100% of the time.

Even with the AA catted downpipe there is a slight drone at certain rpm’s with the valve open. I imagine it would be a bit louder of drone with a catless.

Put your valve back to normal operation and I bet most of the drone goes away. Unless you are driving in sport modes.

[kuzdu]

Originally Posted by Rdurty2

It’s because you have your exhaust valve open 100% of the time.

Even with the AA catted downpipe there is a slight drone at certain rpm’s with the valve open. I imagine it would be a bit louder of drone with a catless.

Put your valve back to normal operation and I bet most of the drone goes away. Unless you are driving in sport modes.

Can't believe it, that was it. everything went away. On my old F22 that wasn't the case with the valve open, but on that car i know there was a mid muffler which prob suppressed that. i guess this valve open at a certain RPM because I'm in sport mode and it's closed.