I guess it all depends on if you have to be emission tested on a dyno. No dyno, ARH Long tubes and choose your muffs. I use the stock ones and it sounds real good. The factory cats are the restriction in the system.
Leaving it stock
Axle back
Cat-back
Ported manifolds
Shorty headers
Hi-Flow cats
Long Tubes
Electronic cut-outs
I guess it all depends on if you have to be emission tested on a dyno. No dyno, ARH Long tubes and choose your muffs. I use the stock ones and it sounds real good. The factory cats are the restriction in the system.
2008 Liquid Red Pontiac G8 Sport/Premium - Adams Polishes - American Racing Headers - ARP - BMR Fabrication - Circle D Specialties - COMP Cams - Crazy Paul - Dynojet - Earl's - Flowmaster - Fuel Air Spark Technology - G2 - GFORCE 1320 - Greg Weld - HP Tuners - JBA - Lingenfelter - Maverick Man Carbon - Metco Motorsports Solutions - Mickey Thompson - M&H - Mike Norris Motorsports - NGK - Pace Performance - Pedders USA - Powerbond - PSI - Russell - SBX Performance - SJM Manufacturing - SPOHN Performance - Tony Mamo - Vararam - Vector Motorsports - Wretched Motorsports - 470 RWHP 427 TQ - Engine Tune By Patrick G
Nothing done yet, but the plan calls for ARH Longtubes w/ stock mufflers. Probably next year.
2008 G8GT, Panther Black
Mods: Pat G Spec'd Cam, PAC 1518 Springs, Trick Flow 7.4 Hardened Pushrods, Pace DoD Delete Kit, Comp Trunion Upgrade, GRRRR8 Heater Hose Relocation Kit,
ARH 1 7/8" Long Tubes Cats & Exhaust, Spectre CAI, Pat G Dyno Tune
412hp/396tq at the wheels
Best 1/4 Stock: 13.6 @ 102
Best 1/4 Modded: 12.49
2008 G8 GT, Magnetic Gray, Two-tone Leather Interior, Sunroof, Bremmer Wheels,
Her Best To Date: 14.0278 @ 101.49 w/ a .0598 R/T!
New R/T Best of .0005 2/22/2012
Not to belabor the point, but how about a category of "shorty headers with high flow cats" and then another one "X pipe".
Looks like you guys are still playing catch up.
Finding a twin 2 1/2" system with no drone will get easier with more development there.
Most here run twin 3" from the header collectors all the way back......it's difficult getting 3" drone free especially with an auto.
Sedans are also a lot easier than wagons, the cargo space acts like a huge boom box.
I am having a custom exhaust done. We had it up on the lift today. We saw no reason to get rid of the factory piping. We are gonna add either an X or H pipe and two aero mufflers utilizing the factory tips.