Z06 H-pipe w/ Corsa X-pipe and LAPD tunnel plate install

[Cobra4B]

Putting a Z06 h-pipe w/ Corsa X on the car along with a LAPD Tunnel Plate... waiting to pick up new exhaust manifold studs to complete the install tomorrow.

Used Corsa X-pipe required a pipe expander to open up the expaned sections of the pipe so I could slip it over the cut H-pipe. Rented it from AutoZone.



Slip X over the cut H-pipe... I cut the H w/ a swazall, made easy work of it.



X vs. factory H. Inside the factory H crossover the actual holes are only about the size of a dime... not the most effective setup.



Z06 setup w/ 2 cats vs. coupe/vert setup w/ 4 cats



Stock tunnel plate vs. LAPD ceramic coated



Plate installed



Will update tomorrow when I get it all in the car and see what, if any, difference it makes. Expecting a little bit more WOT volume and less Corsa motorboat at idle.

-Brian

[Cobra4B]

Picked up $120 worth of 8 new exaust studs and 8 new nuts from GM today... wanted to have a couple spares. Parts counter lady was a bit shocked at the costs, but oh well, no other options.

Install went w/o issue. Used a dab of anti-seize on the manifold studs to prevent galling. Evenso they still went on rough.... very corase threads I guess. Heres $45 worth of studs/nuts


Install complete



As an added benefit I was able to get the tips tucked up a bit closer to the bumper than w/ the OEM setup. I used a floor jack and a board to get them level and up high before torqing the fittings. Still need to tweak them down a smidge to get them perfect, but thats easy to knock out w/ the Corsa Extreme design as the clamp is easily accessible w/o lifting the car.


Car fired up with more bark and settled into a noticably smoother idle devoid of motorboat and exhaust jingle. Driving the car the exhaust note is more exotic as expected as the X-crossover blends the pulses better, pitch is a tinge higher. Popping in decel is still present, but a little reduced, not drastic though. There is a little resonance as you cross the 2500 rpm mark, but once you cross 3500 its gone. At cruise RPMs there is still zero drone and all you hear is the tire noise... pretty awesome.

Time to hit the dyno and see what she makes... no more power/engine mods for this car

[DropTheTop]

Looks great Brian, congrats.

I suspect the hardware is SS, and the nut may even be slightly crushed, or a top-lock design. 90% of the time I have a bad experience when using SS hardware.

[Cobra4B]

No clue if it's SS or not, but I know the ARP fasteners that held my CCWs together were SS and never presented an issue.

Even taking my time and using anti-seize I'd want spares handy if/when removing this go around.

[Peter Pan]

Nice and detailed install