2018 GT MBRP Race catback on a 2017 GT Premium

So, I watched a couple of videos on the new 2018 model of MBRP's race series catback and I'm really liking the sound over the 2015-2017 race model. Obviously, I'd have to buy a quad tip rear valence which I am fine with; however, CJ Pony Parts' website says that this catback will fit ONLY 2018 models, regardless of the rear valence you have.

Can anyone confirm this? I read a post where someone put a 2015-2017 model mbrp catback on their 2018 and it fit perfectly.:shrug:

It will fit earlier models with quad tip valence.

EFI said:

It will fit earlier models with quad tip valence.

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Does it matter which rear valence? I was looking at the MP Concepts GT350 style just to keep it simple.

Edit:
I just got off the phone with CJPP and they determined that it won't fit primarily because of hanger location and not enough room for the Helmholtz resonators. Is there any difference between the 2017 and 2018 undercarriage?

That's odd. My 2018 stock, active exhaust has the same hanger location(s) as my previous 2015. Trunk pan is the same too.

Red65 said:

Does it matter which rear valence? I was looking at the MP Concepts GT350 style just to keep it simple.

Edit:
I just got off the phone with CJPP and they determined that it won't fit primarily because of hanger location and not enough room for the Helmholtz resonators. Is there any difference between the 2017 and 2018 undercarriage?

Click to expand...

Corsa's 2015-2017 GT Cat-Back with the Quad Tips also fits the 2018 GT without Active Exhaust, so i do not see a difference. Properly no-one really tested to see if 2018 Cat-Back Systems for Non-Active Cars fit 2015-2017 GTs with a Quad Tip Rear Valance

Was there ever an answer on this? Does the 18 fit a 17 GT?

Schoonie3 said:

Was there ever an answer on this? Does the 18 fit a 17 GT?

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Both cjponyparts and mbrp state that it won’t fit 2015-2017 fastballs regardless of the rear valence installed but several here have said that the 2015-2017 catbacks fit the 2018 without issue. Also NoReins is saying the 2015-2017 quad tip catback fits the 2018. Im going to go ahead and say with a quad tip rear valence, the 2018 mbrp will fit the 2015-2017 models