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No, US cars does NOT have the particular filter installed, as it is not required by federal law. Instead, we have "baffles" to mimic the back pressure of the particulate filter so that Porsche doesn't need to offer two types of tunes between US and Euro cars.
Originally Posted by mdrums
Are USA Speedster cars coming with a Particulate Filter and Cat?
No, US cars does NOT have the particular filter installed, as it is not required by federal law. Instead, we have "baffles" to mimic the back pressure of the particulate filter so that Porsche doesn't need to offer two types of tunes between US and Euro cars.
Hah, Learn something new.
So my question to the JCR team, do these baffles that mimic the particulate filters take away from exhaust volume ?
For sure, when you put in baffles, it disrupts the air flow which in turns have a dampening effect on sound. I'm just waiting for the some of the bigger names (eg. Akrapovic, GMG, etc) to come out with their exhaust solutions before I make my final decision.
So my question to the JCR team, do these baffles that mimic the particulate filters take away from exhaust volume ?
Absolutely, the new OPF cars in our testing are between 3/5dB quieter than their equivalent 991.2 GT3 RS counterpart. Porsche have developed the matrix in the US cars to mimic the behaviour of the OPF, why they didn’t just run the OPF itself I suppose is probably a question of cost cutting as it’s not required by regulation.
Originally Posted by unotaz
For sure, when you put in baffles, it disrupts the air flow which in turns have a dampening effect on sound. I'm just waiting for the some of the bigger names (eg. Akrapovic, GMG, etc) to come out with their exhaust solutions before I make my final decision.
Look forward to hearing from you soon
JC
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Hi guys,im looking for a aftermarket exhaust for my 991 speedster. as my car has the European exhaust which sounds very muted compared to my GT3RS even when that had the stock exhaust.
Any suggestions ?
Originally Posted by unotaz
For sure, when you put in baffles, it disrupts the air flow which in turns have a dampening effect on sound. I'm just waiting for the some of the bigger names (eg. Akrapovic, GMG, etc) to come out with their exhaust solutions before I make my final decision.
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Come on now, don't keep us waiting! Where is the titanium system? I hope you make that allows the factory tip to be kept on. I like the OEM appearance, but with a much better sound, just like the GMG exhaust for my Carrera GT!
Hi guys,im looking for a aftermarket exhaust for my 991 speedster. as my car has the European exhaust which sounds very muted compared to my GT3RS even when that had the stock exhaust.
Great shots, Thx for sharing
I like the blue tones
Originally Posted by JCR-Porsche
The particulate filter acts as a pretty efficient silencer in its own right, with that in mind and in combination with the latest emissions regs pretty much all late generation cars, including GT will be very quiet from factory.
We have the silencer replacements available now, we had two cars on track testing all day yesterday gathering a huge amount of data
We’re currently part way through development on our Inconel 625 manifold / header replacement which deletes the OPF entirely and replaces the factory cat with a high flow 200cel race cat.
No CEL and no need to flash the ECU. Direct replacement, less than half the weight of the factory headers and a good amount of sound and performance improvement!
Well ahead of the curve on this one. We also have new 718 GT4 and Spyder in too..
Yes due to the baffles (US cars)/particulate filter. Cars will only get quieter from here on forward.
Unotaz, do you find that it's possible also due to the whole folded hood structure blocking engine sound? in a gt3 coupe you get more echo chamber.. in speedster engine and exhaust sound far away? I read that somewhere, haven't driven one yet though
I only sat in my friend's Speedster for about 15mins, so I don't have a lot of seat time in the Speedster yet. Mine won't be here until end of March.
Having said that, I can tell you first hand, with the top up, it's really quiet. With the top down, the sound is much better but it's still not loud enough for my taste. The engine in the Speedster does sound a bit different than the 991.2 GT3, which in turn, sounds different (slightly lower pitched) than the engine in my 911R.
Originally Posted by CAlexio
Unotaz, do you find that it's possible also due to the whole folded hood structure blocking engine sound? in a gt3 coupe you get more echo chamber.. in speedster engine and exhaust sound far away? I read that somewhere, haven't driven one yet though
11-14-2019, 12:20 PM
