Any Rennlisters from New Zealand?
10-23-2013, 01:10 AM
#5611
Rennlist Member
Graeme. The parts hold up on the 991 GT3 (and now 991TTS) was the exhaust supplier so it seems. I think perhaps also some last minute changes as the 991 GT3 exhaust was too loud for two UK tracks from factory (as a few motor journos pointed out). I believe the PDK-S has also received the benefits of an additional oil cooler to ensure longevity.
10-23-2013, 01:41 AM
#5612
They are pretty high on my wish list. Since most run the front one soft I'm thinking OEM may suffice there and so may just beef up the rear one first.
You're absolutely right on that.
From what I read before upgrading, the basic problem is that a good sounding exhaust has a lot more bass tones and in the typical crusing rev range those resonate the parcel shelf, which in turn causes the in-cabin drone. Just leaning over and banging the middle of the 996 parcel shelf confirms that it is just a big drum really. Stiffening the panel with bracing would raise the resonant frequency and likely make it even more intrusive (closer to the human speech range our ears are attuned to). Sticking some heavy sound proofing on (especially near the middle of the larger panel sections as these areas vibrate further) damps it down and drops the resonant frequency below the revs we normally use.
Near the edges of the panels the 'mass loading' effect is nowhere near as effective so for max damping with minimum weight I put several layers on only near the middle of each section, then one layer over it all to tidy it up a bit. Worked brilliantly and only took a few kilos - just half a $75 door kit box of Dynamat.
Took some pictures but Mikelly, I think, has already posted a great how to that covers the key bits. It is super easy really - about an hour or so all up. You do need one particular Torx/reverse Torx though. Mike is one of many who went through several exhausts before getting it sorted.
Id love to hear the Remus...Resonance is the biggest bugbear with aftermarket cans. Its a design issue, not a volume one. That's why you ideally need to get feedback form someone reliable who has lived with the set up to be sure IMHO. Makes getting it right first time very hard in NZ where there are few opportunities to try others with different set ups...
From what I read before upgrading, the basic problem is that a good sounding exhaust has a lot more bass tones and in the typical crusing rev range those resonate the parcel shelf, which in turn causes the in-cabin drone. Just leaning over and banging the middle of the 996 parcel shelf confirms that it is just a big drum really. Stiffening the panel with bracing would raise the resonant frequency and likely make it even more intrusive (closer to the human speech range our ears are attuned to). Sticking some heavy sound proofing on (especially near the middle of the larger panel sections as these areas vibrate further) damps it down and drops the resonant frequency below the revs we normally use.
Near the edges of the panels the 'mass loading' effect is nowhere near as effective so for max damping with minimum weight I put several layers on only near the middle of each section, then one layer over it all to tidy it up a bit. Worked brilliantly and only took a few kilos - just half a $75 door kit box of Dynamat.
Took some pictures but Mikelly, I think, has already posted a great how to that covers the key bits. It is super easy really - about an hour or so all up. You do need one particular Torx/reverse Torx though. Mike is one of many who went through several exhausts before getting it sorted.
10-23-2013, 01:55 AM
#5613
Rennlist Member
Smart thinking. I spent some time talking to the owner of AutoHaus Hamiltons at the Rennsport Weekend in Sydney in May on his chosen method of lightening for a road/track car. He showed me all the key points of noise intrusion and resonance in the 911. The parcel shelf was a key one as were the floor panels in fornt of the rear seats, the seat bases and back as well as the side panels back there. He recommended pulling all the factory deadening out (around 20kg weight savings) then putting around 8-9 kg of a more modern product like dynomatt (he has something even lighter and more space age but I cant recall what it was right now). He believed placing the matt on these these key resonance areas covered 90% of the noise issues for half the factory weight.
All that said best in the first instance not to have an exhaust system that triggers those low frequencies in the first instance. Im not sure how I managed it with mine but although it sounds loud form the outside its actually quiet from the inside, so much so that I can happily talk on my car kit at 110km ph or listen to music. Its all relative however and I know a few who would still say its too loud inside. It masses the missus test tho and she has to sit in it for 2000+ km each year!
All that said best in the first instance not to have an exhaust system that triggers those low frequencies in the first instance. Im not sure how I managed it with mine but although it sounds loud form the outside its actually quiet from the inside, so much so that I can happily talk on my car kit at 110km ph or listen to music. Its all relative however and I know a few who would still say its too loud inside. It masses the missus test tho and she has to sit in it for 2000+ km each year!
10-23-2013, 04:49 AM
#5615
I got my Dynamat from Digital Logistics:
65a Cryers Road
East Tamaki, 2013
09-571 3375
digitallogistics.co.nz
Thanks for the feedback re the adjustable suspension being great on road too. Damn, been fighting the urge to splurge and that doesn't help.
65a Cryers Road
East Tamaki, 2013
09-571 3375
digitallogistics.co.nz
Thanks for the feedback re the adjustable suspension being great on road too. Damn, been fighting the urge to splurge and that doesn't help.
10-23-2013, 04:58 AM
#5616
Rennlist Member
Thanks for the Dynamat info.
Yes, common misconception that coil-overs are harsher. Only truth is spring rates may be firmer. However the bump and rebound is so better managed than a standard strut that the ride quality is much improved by being far more controlled. I was surprised myself going from factory to Bilstein HD to PSS10 over 13 years in the same car and observing significant improvements along the way.
I know Ive been banging on about this a long while but the best improvement that can be made to these cars is not power but suspension, brakes and weight. Weight brings compromise, brakes are relatively cheap and most of the RSG crew have done at least the fluid but suspension is the one often miissed...
Yes, common misconception that coil-overs are harsher. Only truth is spring rates may be firmer. However the bump and rebound is so better managed than a standard strut that the ride quality is much improved by being far more controlled. I was surprised myself going from factory to Bilstein HD to PSS10 over 13 years in the same car and observing significant improvements along the way.
I know Ive been banging on about this a long while but the best improvement that can be made to these cars is not power but suspension, brakes and weight. Weight brings compromise, brakes are relatively cheap and most of the RSG crew have done at least the fluid but suspension is the one often miissed...
10-24-2013, 06:02 AM
#5617
Three Wheelin'
should check out exe-tc too. top of the line suspension and the founder was a kiwi!
older classic line was developed with Tuthill rally boys and the modern line with track/race teams that one Chris Harris was associated with
older classic line was developed with Tuthill rally boys and the modern line with track/race teams that one Chris Harris was associated with
10-24-2013, 06:08 AM
#5618
Rennlist Member
Yeah Graeme....but totally different budget. My PSS10s were "only" $3.6knzd landed. Id guess youd pay double that for the bespoke exe-tc. Ohlins do a great set up but your are talking $8-10K
10-24-2013, 04:33 PM
#5621
Rennlist Member
996.2 GT3 for 80K? http://www.trademe.co.nz/motors/used...-652428589.htm
10-24-2013, 11:23 PM
#5624
Rennlist Member
It will have to wait a while for me. Just drove back from the Tron in the 996TT. Something to be said for cruise control, sound proofing and a turbo torque curve.
As an aside, stopped at HD for a look. Blowing about 30 knots and intermittent rain. Let's hope we don't get the same next weekend.
As an aside, stopped at HD for a look. Blowing about 30 knots and intermittent rain. Let's hope we don't get the same next weekend.
10-25-2013, 12:45 AM
#5625
Racer
All prices NZD delivered in NZ.
NZ (Giltrap) $690
US (TireRack) $510 (+ possible gst)
UK (Design 911) $445. (+ possible gst)
Thanks for those who suggested the overseas contacts.