Hi

This is one subject , that I am an expert in...lol

My 16 valve 928 is the loudest in the UK bar none.... over 130 db at 7000 revs...

But I worked my way up to that in stages and as I also own my own db meter , i think this will answer your questions....

My 86 16 valve is the one with the S4 suspension/brakes AND exhaust system....

First I added an X-Pipe...at 3/4 revs (around 4500) it was 95 db.... sounded a touch better, but not much...

Then I added an RMB , at 3/4 revs around 4500 it was 98 to 100 db and sounded great

Then for my huge Nitrous system once i went over 1000 hp I needed a LOT less back pressure, so the system was and is as follows...

X-Pipe .... NO front boxes at all..... NO middle resonators as all ...rear box is one of the special twin straight through boxes that Paul Anderson makes (after removing my RMB).... PLUS ...ALL my twin pipes from front to rear are 3 inch race pipe...

Decibels...lol...around 110 at IDLE ! and around 130 db at 7000 revs....my engine can go to 8000 plus but I cannot measure that far as my Decibel meter tops out at 130....lol

My advice would be X-Pipes AND an RMB...

Its my daily driver and sounds amazing...but you have to drive extremely slowly near Policemen lol....but when I open it up.... everone and I mean everyone in earshot looks around

All the best Brett

 

I will try X pipe for now then later see if I can get a sports muffler. I dont like how the RMB sounds.

 

Ok, so here is my 2 cents, based on the fact that 10 years ago, I never thought I would be driving a car like I have now. :-)

1.) I have high flow cats, an RMB and an X-pipe on a GT. I bought the car like this. It is loud but more fun to drive than I ever would have expected. Maybe even at times coming off a highway on-ramp on to the highway almost NASCAR loud.

2.) I have received criticism from many people who try to tell me that this does not fit the intended nature of the 928. This is probably true in some way. Probably it doesn't fit the image of a 50 year old either. (oh well.)

3.) It does not sound like an American V8. Somehow, it howls more than it growls. For me it fits the form and color of my car. It is a visceral feeling that contrasts SURPRISINGLY well with the luxury of the 928.

So, my conclusion is, I never thought I would buy either a loud or red car, until I went to drive the one I bought. On the first drive it was convincing enough for me to buy it on the spot.

John

 

I would add a set of high flow cats (see Roger) to the x pipe RMB combo. Takes the edge of it a bit and it smells better.