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Cross pipe

MR997

Well-known member
Joined
5 Mar 2018
Messages
104
H&S or Top Gear? Two ways to achieve the same goal but which is best? The TG pipe flows similar to the original centre box as opposed to the H&S truly crossing over. For those that have fitted either system, have they worked and more importantly caused any issues? Does anyone know if there is much difference in the tone of the sound between the two?

Thanks.
 
I will be purchasing either the H&S or Topgear cross-over pipes in the next few weeks. I'd love to know the differences between the two. I've watched many YouTube videos which don't give a true reflection.

Let's hope for some interesting replies.
 
I have the Topgear bypass fitted on my GTS. Form and fit is great and it's engineered well (and paying £500+ for some formed ss tube seems excessive to me, but that seems to be what the market dictates and as Topgear manufacture as well as sell them, they're able to do it at a keen price point). You may have already seen it but here's a link to the thread I posted with a couple of vids of before and after fitting it.

http://911uk.com/viewtopic.php?p=1400102&highlight=#1400102

I reckon for the money the Topgear one is spot on - got a nice growl under load. Whether it's crossing over or going through a U-bend I can't see making that much difference - it's not exactly pushing fudge through the pipes so resistance is minimal via a U-bend. Askgeez has the Fabspeed one (I think) on his GTS and we've had mine and his running together and I seem to recall we agreed there's not much between them.
 
Watching with interest as I'm about to do this mod soon as well!
 
H&S better airflow, sounds awesome with PSE
 
I got my H&S pipe through a group buy on here for £300. There may be appetite for another as it was a couple of years ago. Ring them up and see if they will come down on price for 6/8/10.

Sounds good over 3300rpm without PSE. Sounds much nicer outside the car than from the drivers seat. I lived with it for 18months before caving in and going for 1.75" banana gundo for another £250 (inc fitting)

The H&S alone adds volume, and rasp at high revs, but with the gundo it makes the sound deeper/throatier and burbles when you lift off. :D

You'll use more fuel as you'll stay in 2nd through 30limits!

You can still drive the car quietly if you keep revs low.
 
I'm very happy with the quality, fitment and weight of the H&S and I've had plenty of compliments on the volume and nature of the noise. 8)
 
Similar H&S fitted here, no complaints at all :D
 
This debate is ongoing about which is best the secondry muffler delete cross over pipes or Xpipes , fabspeed favour one and sharkwerks favour the other have a read on their websites . but it is very much personal choice .
:thumb:
 
MaxA said:
I'm very happy with the quality, fitment and weight of the H&S and I've had plenty of compliments on the volume and nature of the noise. 8)

On the noise thing, I haven't had any complaints, but perhaps I'm moving too fast to hear them, and I quite like the slightly dirty sound from the cross pipes, with some distant rolling thunder as it works itself down the system. Our chaps on security always said they could hear me coming from quite some distance...

It's definitely louder on the outside. I imagine that for real noise, though, you'd need freer flowing/larger diameter manifolds (assuming there's space) with sports cats, as well as new side silencers with less restrictions, or 'straight pipes' (is that even possible?) but it might get you a bit too much attention. And barred from circuits.
 
MaxA said:
MaxA said:
I'm very happy with the quality, fitment and weight of the H&S and I've had plenty of compliments on the volume and nature of the noise. 8)

On the noise thing, I haven't had any complaints, but perhaps I'm moving too fast to hear them, and I quite like the slightly dirty sound from the cross pipes, with some distant rolling thunder as it works itself down the system. Our chaps on security always said they could hear me coming from quite some distance...

It's definitely louder on the outside. I imagine that for real noise, though, you'd need freer flowing/larger diameter manifolds (assuming there's space) with sports cats, as well as new side silencers with less restrictions, or 'straight pipes' (is that even possible?) but it might get you a bit too much attention. And barred from circuits.

Max 100% correct, I have a full cargraphic performance exhaust and its measured at 133.9db and they were not happy about it at Spa :grin: :grin: :grin:
 
I've had the H&S for a couple of years and very happy with it. It compliments the PSE.

I recently passed the sound tests at Brands with PSE turned off at 5000rpm. It originally failed with 103 db at 7000 rpm when my foot slipped lol.
 
Phil 997 said:
Max 100% correct, I have a full cargraphic performance exhaust and its measured at 133.9db and they were not happy about it at Spa :grin: :grin: :grin:

Cheers Phil. 134db is just badass. I have no idea what my 3.8 produces, as I've only ever driven on unrestricted circuits. Not as much as some of the other cars to be frank.

We do have here in Finland a pretty low noise threshhold at Ahvenisto, because it's an old circuit on the edge of a town called Hameenlinna: 95bd at 1m with the microphone held 45degrees from the exhaust at 4000rpm or some such. It's easy enough to pass as a static test, steady throttle. (You may have seen Ahvenisto on Top Gear as it was the circuit that James May visited with Mika Hà¤kkinen.)

My old R53 MINI with a John Cooper Motorsports MINI Challenge 4-2-1 manifold and John Cooper Works catback (no centre silencer) passes the 95db static test, but on the straight, when under load, the car makes a lot of old skool 60's racekar tyre noise (a nice combination of screaming supercharger and wide bore mani), and would probably fail a drive by test ... :grin:

I'll have to link to YouTube as mp4s are not allowed:

https://www.youtube.com/watch?v=pRbYMeiZk1U

Do note that this tiny clip was recorded on a phone ... it would have been better with a GoPro and a real microphone, and if I'd driven next to the wall.
 
MaxA said:
Phil 997 said:
Max 100% correct, I have a full cargraphic performance exhaust and its measured at 133.9db and they were not happy about it at Spa :grin: :grin: :grin:

Cheers Phil. 134db is just badass. I have no idea what my 3.8 produces, as I've only ever driven on unrestricted circuits. Not as much as some of the other cars to be frank.

We do have here in Finland a pretty low noise threshhold at Ahvenisto, because it's an old circuit on the edge of a town called Hameenlinna: 95bd at 1m with the microphone held 45degrees from the exhaust at 4000rpm or some such. It's easy enough to pass as a static test, steady throttle. (You may have seen Ahvenisto on Top Gear as it was the circuit that James May visited with Mika Hà¤kkinen.)

My old R53 MINI with a John Cooper Motorsports MINI Challenge 4-2-1 manifold and John Cooper Works catback (no centre silencer) passes the 95db static test, but on the straight, when under load, the car makes a lot of old skool 60's racekar tyre noise (a nice combination of screaming supercharger and wide bore mani), and would probably fail a drive by test ... :grin:

I'll have to link to YouTube as mp4s are not allowed:

https://www.youtube.com/watch?v=pRbYMeiZk1U

Do note that this tiny clip was recorded on a phone ... it would have been better with a GoPro and a real microphone, and if I'd driven next to the wall.

that little mini did sound very racecar in that clip :thumb: :thumb:

heres a vid taken by a car blogger who films cars in my area ,I found it on you tube my car is at 37 secs in again at 50 secs in again at 1min 10 secs and finally at 10mins 37 secs :grin: :grin: :thumb:

https://www.youtube.com/watch?v=zk5zcEnfeFw
 
Cool. :)

Sorry to the OP. We took the thread a bit off piste.
 

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