Short answer: none. Believe me, I've looked. There isn't even an aftermarket exhaust - a staple for any "modder".
Okay, K&N makes a filter. But in my opinion, a K&N filter causes more problems than the minuscule horsepower increase it offers (oiled up mass-air sensors, poor filtration, etc). And there is an Eibach lowering spring kit. But that is a bit like putting Air Jordans on my 50-year old overweight uncle - he may look better, but he is not going any faster. That rounds up the list of all performance mods that I am aware of.
The DTS does not attract a "tuner" crowd, so despite the relatively high sales volume, no one makes performance enhancements. You are limited to appearance mods, like chrome grills, wheels that happen to fit, and Vogue tires.
Short answer: none. Believe me, I've looked. There isn't even an aftermarket exhaust - a staple for any "modder".
Okay, K&N makes a filter. But in my opinion, a K&N filter causes more problems than the minuscule horsepower increase it offers (oiled up mass-air sensors, poor filtration, etc). And there is an Eibach lowering spring kit. But that is a bit like putting Air Jordans on my 50-year old overweight uncle - he may look better, but he is not going any faster. That rounds up the list of all performance mods that I am aware of.
The DTS does not attract a "tuner" crowd, so despite the relatively high sales volume, no one makes performance enhancements. You are limited to appearance mods, like chrome grills, wheels that happen to fit, and Vogue tires.
Well put......There is really nothing you can do to these cars to get more noticable power unless you are prepared to pay megabucks for serious engine work.People will tell you about reprogramming the injector pulse width,knock sensors and ignition advance......Don't listen to them,all you will do is make your northstar less reliable and you may even hurt it.
You might get a few extra HP that you won't notice and compromise the integrety of your engine.I went the aftermarket grill route and I will soon be getting minor pinstriping.Just enjoy the ride.......
Off topic, but just to highlight differences among the generations, I expended effort to remove dealer-applied pin-striping from my vehicle!
Really.....Wrong color.....?Or you just don't like the look....?Or were they vinyl...?I have the shale (Tuscany Leather) interior with Cocoa dash and am going to have the striping done in a brown to match the Cocoa.....
The pinstriping was well applied and tastefully done. I just don't like pinstipes in general! Like I said - it's probably a generational thing. This is the 7th car purchase of my life, and this is the first time pinstriping was even mentioned, offered, or applied.
It's all a matter of taste, but I can imagine that brown looking really nice if matched to the interior. Another idea might be an ultra-subtle grey - something barely darker than the white, but the hue matching could be tricky.
I think the DTS is one of the few current cars than can pull off pinstriping well. (For example, I have seen a Corvette with pinstripes - if you ask me, it looks flat out wrong because of the deceptively curvy fenders.)
I have the 2006 White Lightning / White Diamond with Shale Interior.
I had the windows tinted real dark and real pale gold pin stripes added to it.
Also had the 3-M Clear Plastic Bra added to the front.
At one time I thought about the HPTuners Deluxe software. Still debating it with myself.
Corsa makes an exhaust for the <05 that should work just fine on the 06+ without much work. It is $$$$ like most of Corsa's stuff, but I love the way Corsa sounds.
Corsa makes an exhaust for the <05 that should work just fine on the 06+ without much work. It is $$$$ like most of Corsa's stuff, but I love the way Corsa sounds.
I've seen that exhaust. What concerns me is the "should work" part. If it was 99% compatible, I'm stumped as to why Corsa maintains that this is only for 2000-2005 DeVilles. They could get some extra sales for "free" by just updating their catalog.
Without someone to verify this, I'm going to assume that some minor differences (such as mounting points or catalyst exhaust diameter) prohibit an exact fit.
Bummer - I would love to try that exhaust out. You can hear how it sounds on this YouTube video:
performance upgrades 
