Maybe I'm stupid for having to announce this, but did anyone realize that d3's 31 rwhp gain was with an axle-back exhaust?? How amazing is it that changing the air filter/tube and the muffler resulted in 31rwhp? I come from the Honda camp where an intake and cat-back yield 8 rwhp. Does anyone think that in GM's efforts to keep the Cadillac brand quiet that they robbed 20+ rwhp from the CTS? At 304 flywheel, adding 20 rwhp would make the advertised number somewhere around 340.

I think this car has serious performance potential, especially with CAFE regulations. The ECM has to have a "fuel economy" tune in it.

For those of us who cannot afford the V, a couple well spent dollars in the aftermarket (with d3) could yield some very respectable performance numbers.

Just a thought...

Does anyone think that in GM's efforts to keep the Cadillac brand quiet that they robbed 20+ rwhp from the CTS?

No.

There have been aftermarket manufacturers advertising ridiculous "peak hp" gains from simple bolt-ons like intake and exhaust forever. A good cat-back exhaust on my CTS-V only netted about 5-8hp, and that's on a car displacing 5.7L, so there's no way a 3.6L could see these type of gains. The largest restriction in the exhaust are the manifolds and cats anyway, not the mufflers or resonator.

As far as intake goes, there have been many tests on pre-2008 CTSs and CTS-Vs, and most agree that the best intake design out there is............. *drum roll*..................the stock one. Here's a link to an intake dyno challenge that the first gen CTS guys did:

http://www.cadillacforums.com/forums/481524-post160.html

At first the result seem to indicate a 13hp gain for the Volant intake, but read it closely- they removed the splash guard and radiator air deflector when they tested the aftermarket intakes, yet left them in place for the stock intake. That makes any results completely unscientific since they could be attributed to the modifications to the car and NOT the intakes (Plus it's pointless to take off the splash guard for a dyno run- you can't drive around like that). Even if you suspend disbelief and assume that the aftermarket intake will still get you 13hp with the splash guard and radiator deflector in place, you're not going to see another 18hp from a catback.

There is a bit of HP to be gained in all stock cars, but I wouldn't expect more than 10 at the wheels from intake/exhaust unless they're paired with headers, high flow cats and a tune.

Nick, pardon me if I missed something, but I think the only dyno results being posted are those by the supplier. With all due respect, I've seen more hp claims that I can even begin to remember that were highly exagerated. It's easy to do - even if not intended, by comparing dyno results with totally different temperature corrections, heat soaked engines etc.

I've been around cars and dyno runs where cold air and cat back exhausts were added quite a bit. 31 at the wheels just doesn't sound feasible to me - especially in this case where it is over 10% improvement. I say we need to wait until a few owners actually run before and after numbers.

I know, the supplier is the one quoting the numbers. I know how to weasel a dyno pull, all of that.

More my point, that didn't come off well last night when I was crocked: They saw a "significant" increase with a muffler and air filter.

On my Hondas and Acuras, all you would end up with was some nice sounds. (and maybe 5hp from a CAI and cat-back)

My thoughts on the V not gaining much in exhaust mods are that Caddy intends that to be an enthusiast's car from the factory, and they would be quite content with a louder exhaust, whereas the base CTS is intended for the general public, and most of them would not want to rumble, and just thought that maybe the stock muffler is SO restrictive in order to keep status quo.

I feel like that came out better.

Just think of what they can do if they replace the muffler bearings with better units!!

Whats the difference between a axle-back exhaust and cat-back system?

I don't know what D3 considers "axle back", but the term is traditionally used when the stock resonators are left in place and everything behind them is replaced (basically just the mufflers and tips).

A "cat back" replaces everything behind the stock cats, including the resonators.

Just think of what they can do if they replace the muffler bearings with better units!!


...and if we flush and fill the seat cusion fluid, and tweak the flux capacitor!!!

I guess I deserved that, my post did sound like a kid who just saw a commercial for GI Joe with the Kung-Fu Grip!:thepan:

...and if we flush and fill the seat cusion fluid, and tweak the flux capacitor!!!

I guess I deserved that, my post did sound like a kid who just saw a commercial for GI Joe with the Kung-Fu Grip!:thepan:
All in good fun my n00bian friend...

I will note that in the 545i/550i E60 BMWs there's a separate activated-charcoal filter under the normal pleated-paper air filter for evap emissions reasons, and Steve Dinan claims they found a very significant HP bump (20HP?) in just removing the charcoal filter.

Crazy things man. Change the intake on a Ford Powerstroke 7.3 and reap 37rwhp!

Hello,
The numbers that were posted are very accurate. We dont fluff up our numbers. The increases in performance were measured at the wheels. If we wanted to make this more "marketing hype" we would have posted what the overall gain was measured at the flywheel.

We were very pleased with the outcome of our testing and proved that will proper engineering and design we were able to substantially increase power and torque. We cant vouch for the "claims" from other companies in the industry, nor are we concerned about their claims. There is a reason we have a filing cabinet filled with dyno sheets and data. We test and prove our products. If you know how to properly calculate the volume needed you can make more power with an aftermarket system than you would with the factory system. We have no problem validating any of our modifications. We look forward to releasing these new products.

Thank you,

Dr. Design
D3 Cadillac

I'm anxious to see exactly what people get out of D3's performance upgrades. For me, it is the performance potential of the new CTS (with aftermarket parts) that will have me either interested or not. The CTS-V is out of my league, pricewise. However, a regular CTS with 340hp at the flywheel would have me very impressed... It would be, in my opinion, possibly the best looking car out there - priced right - and not easily embarrassed by the 350Zs and Hyundai Genesis' on the road.