subwoofer

Thanks. It sounds like it has a lot more bass than stock. To me, it sounds like Fabspeed.

metalone

Very different, this one doesn't have a muffler on the silent path which end up increasing drone as per my experience with CF. The silent path is a non merged smaller diameter pipe path making a controlled crisp and raspy sound. On the other hand the X pipe found here is a direct one not a tangential one like Kline )(, which probably would have a higher pitch on the top. This X Pipe has a moderate high pitch and more progresive rather than explosive sound at the top because when is opened the smaller diameter path is still working.

100% OEM, this exhaust was designed to work perfectly with OEM valves, making an increase in gas velocity at low RPM due to the direct smaller diameter pipe paths, which is a very clever design IMO.

It's the valved one, and would sound bassy only with valves opened at idle, if the valves are closed the sound at idle is crisp without any bass. Either way once valves are closed at around 1000RPM the sound becamos raspy until valves opens again at 4k or 5K, moment when the sound progress to a higher pitched wail sound due to merging gases via the Xpipe.

lowbee

I like BCFab's double X-pipe design for the GT4-RS..... too bad that doesn't fit a regular GT4 or GTS otherwise, I will be all over it.

UncleDude

That is a wild design - not much muffler and some big tubing.

BCFABS

Thanks for taking the time to review our exhaust @metalone Good to hear the sound is improving with more miles and that you finally found the perfect set up!!

We work with Inconel in its softer, annealed state during manufacturing, so for the sound to fully optimize, the exhaust needs to heat cycle to achieve the exotic, high pitched tone. With the materials harder, more higher pitched frequencies are produced than the lower frequencies.

@AnandN @MrFunk
Our 718 RACE exhausts are aimed at those who are looking to achieve maximum volume and save weight. This exhaust deletes the use of the valves and sounds fantastic with lots of character/drama across the rpm range. This exhaust might not be best suited to anyone who daily's their car or anyone who is particularly sensitive to drone. We have lots of happy customers with this set up but our valved exhausts are more popular.

Our 718 VALVED exhausts are aimed at those who are sensitive to drone as it is the valved closed path which is critical for reducing the unwanted frequencies whilst cruising. This pathway offers a considerable increase in quality of tone and volume over the stock exhaust with many owners enjoying this new level of sound/tone in the lower rpm whilst not being obnoxious and maintaining a level of comfort in the cabin.
During development we tested other prototypes which merged this pathway before the X but we found this didn't offer the same level of comfort when cruising, hence why we concluded with the separate pathways.
@UncleDude
Static revving/cruising in the lower rpm, there isn't really much to be gained in terms of sound or performance by merging before the X piece. Above 4000rpm, most gasses pass through the X pipe and a higher pitched tone is achieved. You can hear the subtle differences between valve open and closed in the video below, with valve closed being a considerable amount less volume. This design is also proving to be popular on the 992 GT3's with other brands now starting to adopt our design for the 718 platform.

The parameters to achieve the perfect sound on the 718 are really narrow and to achieve in one area you have to sacrifice in another. As we manufacture all of our exhausts in house we have completed the necessary R&D to ensure our exhausts are the best they possibly can be.
@lowbee Thanks for the support , The Valved double X pipe for the GT4RS works really well but that has the GT3 engine so its a whole different animal with higher velocities of gas and the carbon intakes etc.

Our current range of exhausts for the GT4 / SPYDER / GTS 4.0 have proven to be very popular here in the UK/EU with more and more of our systems being ordered and exported to the US/ROW as time goes on. Feedback from our customers is important to us and we listen and act accordingly.

Here is a video of a GT4 with OPF delete and our Inconel Valved rear exhaust. More videos can be found on our Instagram page, YouTube channel or over email/phone of various set ups.

MrFunk

Thanks for that info.
Was your development done with deleted OPF or with the OEM OPF in place?
What OAP's are you recommending with your system? Or rather, which OAP's were you using in development or in these (OPF Delete) videos?
I'd imagine most US customers will want to delete OPF's if doing an exhaust.

subwoofer

Very nice. Thanks for the information. How much does the stainless steel version weigh and does it sound the same?
Any installation videos or instructions?

UncleDude

Thanks for the reply. Not sure I agree that there isn’t much to be gained valves closed. I’ve tried 2 exhausts (Soul and still have Kline) and the sound from 2500 to 4000 is very nice indeed on the Kline system and there really is no sacrifice that I can see with that system. On yours, I can appreciate the design approach to the valves closed path. When you say “drone” do you mean that annoying resonance at 1800-2200 rpm that certain brands suffer from? Or do you mean constant resonance when cruising (which I think is the real definition of drone). I’ve not experienced any constant drone on any system, but the resonance is there stock and with the Soul system I had. Kline combated it.

I did take a long look at your system and talked to PLife about it when he had it on his 718. Ultimately I went another way but I admire the craftsmanship and different design approach.

Jon H

I have the 718 Inconel Valved exhaust on my GT4 (rest of system is stock) very happy with it.

BCFABS

Development of the rear pipe was completed with every set up including our headers, stock headers, OEM OPF, Our own OPF delete etc.
Non silenced OPF delete with our valved rear pipes offers the best improvement in sound and performance for US/ROW cars. You can pair this with our headers too which sounds incredible but this set up isn't for the faint hearted as this brings the car to cup car level in terms of volume. We have a few customers running full exhaust systems with our equal length headers and UAP (under axle pipe) 200 cell cat and valved rear pipes in both Inconel and stainless steel. Anyone interested in full systems, we have a new valved rear pipe due for release soon and to be used with aftermarket headers only, bringing the car to a more sensible level of volume with great sound and maximum performance. Watch this space...

The video above is running Stainless OPF delete heat shielded with our Inconel Valved rear pipe and OEM style rolled tips with Inconel finished in black. If you were to choose Inconel OPF delete the sound would be slightly smoother and offer a slightly higher pitch. The largest differences in sound is which material for the rear pipe as the X pipe is what increases the pitch and tone as the revs climb.

Sound is subjective and unique to each individual's taste. Inconel offers a sharper, exotic tone with a higher pitched howl across the rpm range. The equivalent in stainless steel offers a deeper, classic Porsche flat 6 sound. Both materials sound fantastic with lots of happy customers with each.


Our Stainless Valved exhaust with the rolled tips is 12 lbs lighter than the OEM box. If you delete the OPF, 15lbs saving. Total 27lbs lighter than the OEM exhaust. If you went for the Inconel there would be more weight savings.

Its quite difficult to capture the differences in sound on videos between the 2 materials as they both use the same engine but if you were to hear in person you can tell the difference quite clearly. We can supply install instructions/video if required.

Stainless steel valved rear pipe with stainless OPF delete

subwoofer

Link to an old thread I found: https://rennlist.com/forums/718-gts-...ved-in-us.html

I'm not a fan of loud exhausts but I have to say that it sounds very nice even with just the rear section. Nice videos with sound. It reminds me of the 3.4L in my old Boxster with the sport exhaust.
My Boxster 25 is quite muted in comparison below 4k rpms.

Agcsr25

My BC Fabs system with oap, valved x pipe and ceramic tips

Flyby with valves open

You Tube

subwoofer

Sounds very good. How is the sound inside the cabin? Are those OAPs from BC Fabs? Your exhaust, SS or Inconel?
I ordered just the exhaust in SS from Ben last week.

Agcsr25

Oap and X pipe rear are inconel from BC Fabs. It is interesting how the sound is changing with heat cycling and use. It is getting more high pitched and the initial boominess is going away. It works great with the oem pse. With pse on I was getting some boominess in cabin between 800 and 1200 rpms (this is what is going away with heat cycling) but it is completely absent with the pse off. No drone cruising at highway speeds. Workmanship is phenomenal and does not take a backseat to anyone including JCR and Akrapovic. I have a friend with a Kline exhaust and he agrees BC Fabs workmanship is at a different level. Another buddy has JCR and their quality is also top notch. He seems to have some drone cruising at highway speeds but nothing that would be a deal breaker. I enjoyed driving my gt4 before the exhaust change but now I just can't get enough of it with the new exhaust. Feels like it has more torque down low but cannot absolutely confirm that. Plan to get it on the dyno soon.

subwoofer

Excellent to hear. Thanks. Should work very well in my Boxster. I will decide later whether to add the OAPs if the rear box is not enough for me.