599 exhaust valve bypass

Pull off the small hoses that attach to the exhaust valves and plug the ends of the hoses.
Better still, just wire the valves open with some stove pipe wire - I did that - when I had enough, I just cut the wire from the back - did not even have to get under the car.
No permanent issues doing this, although on occasion, it may set a code, but it seems to self correct when the engine is shut off.
It makes the car louder under 3500 rpm or so. (NOt better, just louder). I did not like it, so I put in a set of Tubis.

 

Ive heard it with the valves open and it doesnt sound that great. Get an aftermarket exhaust instead.

 

baron- I think you might be happier with an exhaust designed to pass the same amount of exhaust gasses through all four pipes. Right now what you have is an exhaust that passes all the gasses through two tailpipes at low revs and most of the exhaust gasses through two different tailpipes at higher revs. If you want a pipe organ, it should be tuned to what you want to hear. Ask that question instead and you probably will get an answer you like and a system you can love. Be prepared to give up a little low end torque for the glorious sound, and, possibly, to gain a little extra high rev hp. Careful, though, some systems are really (and I mean really) loud. Too bad there is no factory HGTC 599 exhaust, like there was for the 575M and 612. Glorious sound there.

Taz
Terry Phillips