CarHopper

You tuned for headers yet? Or stock map?

GRam

Sorry, yes, EC V5 header tune ...

Mort

For the vibration, look underneath and see if it is possible the pipes might be vibrating on the cross support in front of the resonators.

I found the tune took a while to adapt after I put the EC V4 and MBH LTHs with catted mids and x-pipe.

GRam

Mort
Did exactly that last night after a short trip to town and back. Didn't have the car up on stands or anything, but laying on the floor and using the flashlight, certainly looks like it's rubbing on the trans crossmember.
I was just going to use some 1/4" aluminum flat stock and make a shim for each side.
Is there something else folks are using? I seem to recall reading a header thread and this problem arising, and some were just running without it?
I don't want to go that route, if possible..

GRam

Oh and Jerry @ EC suggested disconnecting the battery overnight. WIll try that as well. We did a fault code search pre/post tune install, nothing showed, so not sure if the disconnect thing will do anything? Can't hurt though...

Mort

The tune will have to adapt a little for the extra air flow caused by the more free flowing exhaust and increased scavenging caused by the headers. It will not necessarily set a code but you will feel small hesitations and perhaps flat spots in the cars performance which will likely disappear as you put miles on the car and the tune adapts for the increased airflow. Drive hard for the best performance.

If the headers are rubbing on the trans mount you will need to find a way to move them so they do not touch the mount or trim the trans mount so they do not touch. It is the cross bar under the car in front of the resonator that is often a problem as the headers often hang lower than the stock exhaust which has a bend in it to go over top of the bar. If the headers rub on it you will get a very annoying noise. There are some posts about it happening in other header installs. The bar just goes from one side of the under carriage to the other, as a brace and is not a mount for anything. If it is rubbing you may be able to loosen the clamps and move the exhaust up a little higher or if not you can shim the bar down or remove it all together. It does not seem to affect anything if you remove it but MB put it there for some reason so best to see if you can adjust the fitment of the exhaust or shim the bar down.

I am Jeff

Graham -
I just saw your post about your headers finally being installed. The fluttering sound that you are talking about is due to your headers dropping lower a bit after a few heat cycles. Since the header sections are all held by clamps, the newly installed clamps will loosen after the first few initial heat cycles. Have your installer align the rear pipes upward so that they are not laying on the metal cross bar. I solved it by adding quarter inch spacers to lower the bar so that the rear section piece has some additional clearance. That will completely solve your issue.

How are your initial impressions of the c63 with the headers?

GRam

Mort/Jeff
Yup, buddy and I are going to build and install some spacers tomorrow, and loosen the clamps and rotate them up as much as possible, problem solved.
Love it, sounds like a pissed off babboon on a cold start now hahaha.
Took the usual way into tow, which has a highway on-ramp about 300 meters long, left turn onto it, squeeze the pedal some, kicks down into 3rd and starts wiggling the tail around, never had THAT happen before lol.
Needless to say, I'm "happy" with the results, and once the crappity rattle is gone I'll be "ecstatic"

GRam

Well colour me "ecstatic" lol.
Pulled that bar out, going to weld a 3/8" thick piece of flat bar to it, to shim it.
Currently have the bar out, and voila, no more noises that make my tummy hurt lol.
Looking forward to road trip with it coming up on SUnday, doing a one week, 1800 mile loop to go visit friends/family.

I am Jeff

I experienced the same issue with the fluttering sound, I was perplexed for the longest. My first thought was that the headers loosened from the engine, but they were tightly bolted to the block. I started hating driving the car because of that absolutely horrible sound. I turned around to walk away frustrated, and I noticed that the rear section of the pipes were lying on the crossbar. Once adjusted, the car was a blast to drive.

Enjoy your roadtrip!

CarHopper

Glad you got everything sorted out. Some good help on these forums lately.