VIDEO https://www.youtube.com/watch?v=49joD2ZHc9Y
Sawzall pipes as close as possible to front of mufflers...AFM valves retained...no need to remove lower rear facsia.
Weld new stainless pipe, attach tips & hangers.
4.5" double wall stainless, mirror polish custom tips...slash angle matches fascia cutout perfectly...largest tips possible.

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OK, now you've got me interested and excited.

More info please, and any actual install pics.

I have pulled fuse 41, so my NPP is open ALWAYS, so this should now be AWESOME.
Any problems with pulling the fuse? Will the actuators get stuck if they are not used for some time?? Seems the easier the exhaust escapes the better the mileage/performance??
Tips just arrived...install soon...stay tuned.
M7...only way to activate AFM valves is ECO mode/7th gear which I'll NEVER use. Didn't order NPP figuring I'd opt for a more aggressive custom set-up with larger tips...costing less.
Also, M7....

As Jake says, the AFM valves only work if in Eco mode.... likewise, I'll never use that.

As for the NPP valves... they are normally open.
When the car is using little power (RPMs, and some other determinants),
the valves close electronically.
Using the Mag ride selections, these valves still do work.... even if you have
turned the option to "Off" in the driver options selections screen.

But, by pulling fuse 41, they CAN'T work.... therefore ALWAYS open.
On the 8 speed automatic, any problems pulling fuse 41? Will it throw codes?

In the DIC, there is a setting for how you want the car to sound.
By setting it to " track", does that not hold the exhaust open all the time? Or does that do something else?
With automatic....
It WILL go into ECO mode....again depending on various parameters.
If using the other possibilities (mag ride), AND using the options setting to be always
"open", it STILL will close those NPP valves, depending on certain conditions.

The only sure way to keep the NPP valves open is to pull the fuse (41).
It will NOT set any codes.
This is all from a very learned person on the other Corvette forum.
OK, now you've got me interested and excited.

More info please, and any actual install pics.

I have pulled fuse 41, so my NPP is open ALWAYS, so this should now be AWESOME.

I took a look at the fuse box panel. Fuse 41 shows as washer pump. Just to clarify, are the NPP the butterfly valves in the outside exhaust tips that open and close depending on the selector mode?

Is your fuse 41 on the inside of the fuse box lid diagram showing washer pump or NPP?
It's the 20 amp fuse.....

Jake... good pics.

Just as added information regarding "loudness"....

On my 2012 Camaro 2SS (V8), I bought the SLP Loudmouth II exhaust.
Fundamentally it involved cutting out and removing the rear mufflers,
and replacing them with straight though pipes with SLP tips.

Of course, it is louder.... but certainly not anywhere near as loud as it
would be without Cats. We (my wife and I) both like the sound.

So I expect we should also like the expected sound coming from this
modification for the C7. We do have NPP with the fuse 41 pulled,
so the rear valves are always open. But with the Cats, I expect it will
just be louder than we have now... just like the Camaro is.
now this is odd.

All info on the other Corvette forum relates to fuse 41.

I pulled fuse 41 on my 2014.

Aha..... it turns out the 2015 is DIFFERENT.... Indeed it is fuse 42 on a 2015.
I just measured the tips on my Z51 NPP....

4.5 inches across the height (slanted) of the pipes,
and 17.5 inches from side to side.

I wonder if the ones you show will actually fit the opening?

It'll be interesting to see your results, AND to hear a good sound clip.

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