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Today I have been mostly ...

GT4

Well-known member
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8 Nov 2008
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30,181
... grinning from ear to ear.

Especially after 3k rpm's, with the windows down or on heal-and-toe down changes :cloud9:

My car's mufflers have been Hayward&Scott'd

Not my car, but to give you an idea of the work:

1sb_231.jpeg


My car is pictured in the attachments, but they were so quick to finish my car (just over an hour), I didn't get to take piccies of finished work before the car was returned back to the ground (and I had returned from a walk to, erm, Sainsbury's cafe for a full english round the corner :oops: ).

So I have a picture taken from the point of view of the exhaust cut-out in the bumper.

EDITED: as I just realised I spelt their name wrong :oops:
 

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Shame you cant post a sound file :lol:

How much did it cost??
 
Jedi,

exactly what I'm after. Bored of the my current exhaust note. I've had a look on the website you listed, but can't find the mod you described (only replacement exhausts etc). Did you have to speak to them for a bespoke service?

Cheers,

Sean
 
wingsweep said:
Jedi,

exactly what I'm after. Bored of the my current exhaust note. I've had a look on the website you listed, but can't find the mod you described (only replacement exhausts etc). Did you have to speak to them for a bespoke service?

Cheers,

Sean

Thanks for my official rank title, but a simple GT4 will suffice.

The mod is bespoke in the sense it is not an exhaust system per se (about 2x10cm of stainless steel piping).

They do them all the time (Boxster, Cayman, 996, 997).

Do a forum search for Haywood and Scott on 911uk, PistonHeads, Boxa.net, RennList/RennTech.

Boxsters are ALWAYS down there (I guess they sound even more anodyne without PSE).
 
What diameter pipes did you go for GT4?

I understand that the bigger the throatier (within reason I guess).
 
They are 1" diameter, as per PSE1 (996.1 / 3.4) specifications. Bypass is direct entry to exit bridge.

It is true a larger diameter will allow both different harmonics (and dominant frequency) and more gas flow (noise). However, these also depend on the overall system parameters aswell.

A 100% bypass is offered on Carerra Cup GT3 race cars for instance (no mufflers at all and 2.25" pipes, from cats or manifold as required, to tips)

These are not road legal and deafening.

The characteristics of the 3.4 and 3.6 engines require different muffler and PSE (or bypass) designs.

I have a 3.4, so I had a PSE1 mod to match the official PSE output.

My exhaust noise may be slightly different (noisier?) as the X51 breathes and exhales in a slightly different manner (consisting of alternative size, profile and/or material intake and exhaust manifolds and alternative cat system on the 3.4 X51)
 
Having had Hayward & Scott do the same bypass on my back boxes about a year ago (maybe a little more) I can assure you I am still very happy with the job and the sound it produces.

And I drove there from Bournemouth (although I did have an appointment in Basildon to go to at the same time).

I've even got a spare set of exhausts that I am considering getting an alternative sized pipe attached to.

:thumbs:
 
Very informative post GT4.

My car is a 3.6 but also has the X51 engine so I wonder what the best route is for me? I understood from previous discussion on this that 3.6 cars could use either the PSE1 or PSE2 mod, but maybe I need to chat to H&S. I called them a few months back and they indicated it would be a pretty straghtforward job but I didn't go through which mod would be performed. I suspect they were just referring to the 3.4 mod directly from entry to exit pipe.

My other option under consideration was the Carnewal RSR mod. Anyone know how that one works in comparison?
 
To match PSE2 (996.2 / 3.6) spec you need a 2.25" stage 2 bypass (from corner nipple).

See here:

post-24953-1209107872_thumb.jpg


http://911uk.com/viewtopic.php?t=47901&start=30

The muffler design etc means this is inadequate for a 996.1/3.4, but exact match for 996.2/3.6 PSE2

A PSE1 type bypass (on a 996.2/3.6) will be louder, a PSE1 type bypass with 2.25 will be louder still!

Your X51 will have slightly different intakes/exhaust manifolds. However, I do not believe it has an alternate cat specification to standard.

The 996.1 X51 has a few more bits than the 996.2 X51, but that is because the 996.2 has a higher standard specification (eg cooling adequacy, cylinder swirl etc).
 
Thanks GT4. Seems like I do still have choices available then. Hmmm, what to go for? :?:
 
Am assuming the mod is road legal?

Very tempting - I wonder what it will sound like coupled with my K&N CAI?
 
As it matches the official PSE noise (unless you go mad with full GT3 Cup bypass), it is unlikely to be illegal.

With my Schnell CAI/K&N panel it sounds lovely. Nice fruity rasp.

Plus, if you can restrain yourslf from the aural treat, you can burble round almost silently below 2k rpm and 1/4 throttle.
 
I think you'll find it increases fuel consumption by about 3-4 mpg - because you just can't resist flooring it for the sound over 4000 rpm!
 

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