I worked in final fitment of the PPE downpipes with Mike, Paul at PPE, and BMR last year. We did multiple dyno pulls after each one was fitted. Fitment at Paul's shop, dynos at BMR. Did catted (Magnaflow high flow cats), non-catted, and ceramic coated DPs all on my '13 SHO with stock tune for this and also did stock DPs... all same day. For details of the process check out the "How To" I posted with the story of that day and a bunch of pics. The whole process and pics is here:
http://www.ecoboostperformanceforum.com/index.php/topic,2054.msg28591.html#msg28591
Construction: PPE does an absolutely super job in all respects including ceramic.
Sound: Sound definitely deeper and more authoritative and still near silent when cruising, but remember it's a V6..don't expect 80's muscle car sound. A little more sound at moderate acceleration. I am talking cabin sound with windows up.
Power: max increase horsepower was 17WHP with non-catted, max increase with catted was 12WHP, ceramic coating is only aesthetic... A BIG note about power... dyno showed it, and I can feel it... The DPs caused the turbo's to spool about 500-600 rpm earlier (1500-1600 rpms now) in all versions. Stock exhaust results in turbo spooling about 2100-2200 rpm... This allows quicker access to AWHP and Torque. This effect really makes a difference on the low end power! It starts earlier and nothing lost in the upper power band... Tunes can be modified to optimize these effects. Both Unleashed and LME have mods for DPs. The car does idle a bit slower both then with stock tune and now with modded LME v8 tune...about 600 with AC on.
No odor ever...
If you go noncatted and remove the third cat you will have that hot metal and oil smell..
Fitment is true bolt on. The trick is improve flow of course... the pics I posted show why
Install: It really is best done on a lift, not only for install, but checking for leaks.
If you go noncatted save the stock pipes... any and all tuning for
noncatted DPs includes turning off the O2 sensor in the passenger side DP which is done to keep from throwing a CEL (which will return even if cleared)... In an emissions state, at least AZ, they hook up OBD2 to verify that the emissions system is functioning... car fails if it's not. This O2 sensor is part of that system.... even if you don't need the OEM pipes now, you may if you sell in the future
I did catted in black ceramic on 404 stainless (AZ is an emissions state).... I love them. I would not drive the SHO without them. Dealer does my service.. No problems with these Downpipes, Hotpipes, MDesign CAI.
