So, a few weeks back, after anxiously awaiting their release, my cp-e™ SS 3" catless downpipes finally arrived. Much like their catback exhaust, I'd been bugging cp-e™ for a while about when I could expect them... Mind you this was somewhat pointless though, since my car had been in storage since November. I guess it was just a matter of having them in my possession so I could "test" them as soon as my car came out for the season.
(Click for larger images)
Here they are in all of their glory, prior to Hi-temp coating:
After admiring them for a few minutes, there were a few things that I immediately noticed:
- The cast bellmouth housings are AMAZING quality. It was clear that all of the R&D was worth-while after just a quick inspection. These are something that EVERYONE building downpipes should be doing!
- The overall quality of the rest of the pipe matches that of the housings. Great steel, nicely polished, etc.
- The flanges that connect to the catback section of the exhaust are HUGE. You won't see any warping with these...
- The lack of bends and smooth flow of these pipes is incredible... Even more so when compared to stock (later on in this review).
So, after some debate, I finally decided on having these ceramic coated. I honestly was (and still am) not sure if this has any positive affect when running downpipes on the N54; however, it was pretty common in the Subaru community in which I was previously involved in... So I figured it couldn't hurt anything. I went with matte black on the outside (good for temps up-to 2000 degrees) and silver on the inside (which is
supposed to aid in flow of the exhaust gases).
While I was at it, I had the catback done too (helps to "stealth it up" a bit):
Here are some good comparison pics prior to the install. Note how perfectly everything is aligned... The angle of the bellmouth and exhaust flange(s), location of the O2 bung(s), etc. These pipes are absolute perfection and I knew it prior to ever installing them.
With regard to the install, there's honestly not much I can say... These went in like butter and there were ZERO surprises. The ONLY adjusting whatsoever involved rotating the downpipes to the same position as stock prior to tightening the v-band clamps. As-mentioned above, fitment of everything from the bellmouths & v-bands to the four O2 sensors, right up to the catback were perfect. They all mated right back up identically to stock. If it weren't for these being catless and the cp-e™ logo on them, one could have mistaken them for a superior OEM unit... Maybe BMW should talk to cp-e™ for the '10-'11 models!
Here are a few random pics during the install:
(Know thy enemy... Silly power-robbing cats!)
(I love the smell of RTV in the morning...
)
(Exhaust tips still exit perfectly with a mildly aggressive protrusion from the rear valance.)
(As-if it didn't look awesome before...)
My final words for the install are these:
DO THIS INSTALL ON A LIFT... or better, yet, just have a pro do it! Don't get me wrong, I pulled it off without a hitch. No leaks, "tweaking," etc. - like I said, cp-e™ did an awesome job manufacturing these; HOWEVER, I am not a contortionist and am guessing that most of you aren't either. I actually had access to a lift, but it's around 45 minutes away from my house... I figured the drive was more hassle than it was worth and took a stab at it this way. The 45 minute drive or $170-$250 it would have cost to have these installed would have been TOTALLY worth-while. I didn't keep track of how long it took, but it was more than the 2-3 hours most claim... and, in my feeble, shade-tree mechanic defense, I had the day off of work and decided to take my time so not to get frustrated
and to take pics/notes for this review...
On to the important stuff... The impact they've had on the car! Much like my review on the
cp-e™ Cat Back Exhaust, I'm not going to comment much on power. This is for two reasons... First and foremost, I wasn't able to dyno the car prior to and immediately following the install. I *hate* speculation and for me to say, "I undoubtedly picked up 25+ whp from these pipes" would be unfair to all of you reading. I'm very much a 'dyno snob' and don't trust anything shy of a Mustang dyno... preferably the one I roll my cars on at
Speed Industry in Troy, MI. I don't want to start a long debate here, but if it's not actually applying a load on the vehicle, it's not accurate for anything other than before & after #s. SECONDLY, this wasn't the only power-adder installed on my car since it went in to storage... An intake and tune have also since been installed and they've also had a positive affect on the car's ability to shred the rear tires!
That said, I *will* speak on the throttle response here, which is IN-@&#*-CREDIBLE. I've had several people in the car since these pipes have been installed, two of which are seasoned drivers. One of them personally drove the car and the other (who is PAID to drive, mind you) had a fair bit of time in the passenger seat while I did some spirited driving. They've ALL noticed the car spools up much more rapidly and those that have driven it took immediate notice to the change in the throttle. As-if the pedal didn't already feel great on this car, adding these pipes have livened it up even more!
As far as sound goes, I'm going to keep this simple... It's really easy to explain and if you've read this far, I'm assuming you're enough of a car fanatic to be familiar with the RB26DETT. For the laymen, this is the motor that's in the past few generations of the Skyline GT-R. I'm sure some BMW (
and Skyline) purists will call this blasphemy... but the car now has a very similar tone to a highly-boosted version of that motor/car. Some may call "BS," but if you look at the specs on the N54 vs. the RB26, it makes sense! Also, IF your car has a Steptronic and the cp-e™ cat back, GET THE RESONATORS. My car is Step-equipped and can tell you it's LOUD and it drones a fair bit. I'm holding off on videos until I get them installed... I can tolerate the loudness and droning, but my wife hates it. The resonators will definitely correct this though. You've been warned.
Lastly (but certainly, not least), I'd once again like to throw a shout-out to
Custom Performance Engineering for building
another DAMN nice upgrade for our cars. You guys (and gals) have once again outdone yourselves!
Link to the downpipes:
304 SS 3" Downpipes
