Turkis Blue ST Hot Rod

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Ferry Man
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Post by Ferry Man »

I've been larking about with exhausts.
I'd been interested to see how noisy the ST exhaust was and I saw this on offer at Maplins. £29 inc delivery. Bargain.
OK, it's probably not very accurate at that sort of money but for comparison purposes it'll do. I was interested how the new exhaust system compared to my old 2.4S and 993RS.
Don't consider the figures accurate but merely useful to check against each other.

Image
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
Ferry Man
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Post by Ferry Man »

To keep things more or less consistent I taped the tester to a piece of plastic 0.5m long.
All the recordings were done at a steady 4,500rpm.
To put things in context the 993 gets on at just about any trackday. 99db, no problem.
The metallic green struggles sometimes even with 105db days. It gets through but only just.
As for the 2.4 getting on at 101db? No chance. Castle Combe is impossible. Mind you a Tesla would struggle with those people...

And the results are...
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
Ferry Man
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Post by Ferry Man »

So firstly the 993:

Image

As expected, pretty good, nicely muted and respectable 97db (by this uncalibrated device).
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
Ferry Man
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Post by Ferry Man »

The 2.4S (a car which has always seemed noisy):

Image

Yep, noisy, tinny and shrill (SSI's & stainless back box) with a hooligan 103db.
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
Ferry Man
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Post by Ferry Man »

The ST with modified back box (in steel)...

Image

Sounding nice and not too embarrassing with a modest 101db with the caps on.
Taking the caps off reveals a much more impressive, deeper, racer type noise and ups the ante to 103db.

So, it's no noisier than my standard car even with the caps off.
With the caps on it might even get on a 101db day.
That may be ambitious but I certainly don't fear a 105db day.
Track days here we come. :)
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
964RS
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Post by 964RS »

Fantastic - get it on the track!

My 964RS is 104.5db static when lying about my revs :wink: (it was 109db with the cup pipe in place) and no idea what the RSR is but the 64RS sounds very quiet next to it!!!!

Doubt I'll be going anywhere with static testing.....looks like I'll be doing drive by short shifting! 8)
Ferry Man
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Post by Ferry Man »

964RS wrote:Fantastic - get it on the track!
Yes, and I'll be interested to see if 'caps off' makes any difference to the power output. Once it's run in a bit I'll get it on a rolling road and see.
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
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hot66
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Post by hot66 »

interesting results Paul. My 2.4S with steel H/E & SS back box was 105 at Goodwood at 5400 ish rpm

Remind what the full system is on the ST ?
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
Ferry Man
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Post by Ferry Man »

hot66 wrote:at 5400 ish rpm
5,400rpm :shock:

Well James, I think our cars are going to be very similar.
My 2.4S normally tests at about 105db at Goodwood too.
I'd expect to be tested at roughly 4,500 though.
Interestingly I did all those tests above at only 4,000 rpm (as opposed to 4,500) and each time it was fully 2db less.
If you can lie about your revs it helps. :wink:

The ST has stainless heat exchangers and a steel back box.
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
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hot66
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Post by hot66 »

I'm sure they were working on 3/4 max revs ???

There is a good argument for getting a rev counter from a 911T with a lower redline ;)
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
sladey
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Post by sladey »

hot66 wrote:I'm sure they were working on 3/4 max revs ???

There is a good argument for getting a rev counter from a 911T with a lower redline ;)
Even better argument for getting a spare rev counter and some orange paint
The simple things you see are all complicated
I look pretty young but I'm just backdated yeah
Ferry Man
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Post by Ferry Man »

hot66 wrote:There is a good argument for getting a rev counter from a 911T with a lower redline ;)
I like your style, you devious so and so. :lol:
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
marksgtv
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Unbelievable

Post by marksgtv »

What a fabulous thread. Paul, congratulations on an amazing build and a suburb car. I love it.
Mark
left4dead
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Re: Unbelievable

Post by left4dead »

marksgtv wrote:Paul, congratulations on an amazing build and a suburb car...
Couldn't agree more - all very suburban. How about something a bit more racy for your next car? :wink: :lol:
Steve

1 x '67S, 3 x 2.4S all RHD

A privilege & pleasure to have owned them all.
Ferry Man
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Re: Unbelievable

Post by Ferry Man »

left4dead wrote:Couldn't agree more - all very suburban.
:lol: :lol:

'Might start with a Panamera next. :wink:
Paul

'74 Porsche 911 Carrera 2.7 (MFI) - Lime Green
'94 Porsche 911 Carrera 2 (993) - Mexico Blue
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