996tt at high speeds
996tt at high speeds
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666TUR

Original Poster:

69 posts

173 months

Saturday 21st July 2012
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I recently had my 996 on derestricted autobahn for the first time, at over 160mph It felt hairy, this is nt meant to be a stupid question but do others car feel the same at very high speeds?

I bottled it at 170mph, the wind noise was very loud, the drivers window seem to have a seal issue and vibration in the steering. The car has done 40k and well maintained. Is this normal?

Other than that been able to really joy the car on the autobahns and into the Alps has been fantastic and highlights what a superb piece of kit these cars are. It's averaged 24 mpg and been a pleasure to drive. Highly recommend an European in your Porsche.

Terminator X

20,814 posts

234 months

Saturday 21st July 2012
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Doesn't sound right to me. My C2 should do 173mph and I'd expect it to when needed.

TX.

anonymous-user

84 months

Saturday 21st July 2012
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I've had mine to 140, and it was rock solid. More so than at 110. The front end goes through a stage of feeling light at that speed, then settles down once you go faster.

Dunno about above 140, but there were no warning signs at that speed of trouble ahead.

Magic919

14,555 posts

231 months

Saturday 21st July 2012
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I've had both 996s up to that kind of speed and they were both great. The vibration could well be wheel balancing. I found going somewhere with a better machine and getting them balanced to tighter tolerances helped above 140. I use Wheels in Motion/Blackboots for that.

Can't really comment on the wind noise. Hardly going to be quiet at those speeds, but maybe the seal or window are a bit out of place. Might be worth getting it checked.

666TUR

Original Poster:

69 posts

173 months

Saturday 21st July 2012
quotequote all
From UK to Germany I had noticeable wobble at 130mlh, the car went to OPC Cologne to have all for wheels balanced. There was an issue with rear wheel weights and sorted with impressive german efficiency. The service guy reckoned they had several English customers, also plenty of 996s being worked on, don't see that often in UK now.

I think I need to try it again on smoother surfaced motorway and not the rough stuff. Certain sections of the autobahn have no barrier along hard shoulder and straight into a slight bank and trees. I found it off putting.

Porkupine

1,722 posts

195 months

Saturday 21st July 2012
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Have you had geo checked?

666TUR

Original Poster:

69 posts

173 months

Saturday 21st July 2012
quotequote all
The geo set up has not been checked, I rarely drive the car really fast in the UK so had never noticed the issue. The tyres appear to be evenly wearing, ie the rear inner edges before the rest. Drives straight, no obvious issues it was only at very high speeds.

I am giving it a run on the
Route Napolean tomorrow and start heading back to uk. So may get a few more chances at high speeds.

davek_964

11,318 posts

205 months

Saturday 21st July 2012
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My car has always been very stable at high speed (150mph+) - even when my alignment was quite far out, it was still very stable in a straight line. On a track obviously.....

666TUR

Original Poster:

69 posts

173 months

Saturday 21st July 2012
quotequote all
It was stable, it would cruise at 140mph very comfortably it was a combination of the wind noise, steering vibration etc that spooked me, I do wonder if the road surface had something to do with it.

IMI A

9,997 posts

231 months

Saturday 21st July 2012
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it should be very stable all the way to 190 mph. they're very sensitive to badly balanced wheels

S1MMA

2,451 posts

249 months

Saturday 21st July 2012
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My GT3 is stable over 170 mph indicated speed, feels planted. I can feel the aero at these speeds pushing the car down a bit, it feels a bit more weighty.

Don't forget 170mph on the speedo is only 155-160ish in reality. A true 170-180mph takes some going. 190mph+ even on the autobahn is hard work without 600-700bhp+

Gouki

352 posts

214 months

Saturday 21st July 2012
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S1MMA said:
My GT3 is stable over 170 mph indicated speed, feels planted. I can feel the aero at these speeds pushing the car down a bit, it feels a bit more weighty.

Don't forget 170mph on the speedo is only 155-160ish in reality. A true 170-180mph takes some going. 190mph+ even on the autobahn is hard work without 600-700bhp+
I suppose we will give it a good go in less than a month! (GPS not speedo of course)

911god

2,961 posts

215 months

Saturday 21st July 2012
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S1MMA said:
My GT3 is stable over 170 mph indicated speed, feels planted. I can feel the aero at these speeds pushing the car down a bit, it feels a bit more weighty.

Don't forget 170mph on the speedo is only 155-160ish in reality. A true 170-180mph takes some going. 190mph+ even on the autobahn is hard work without 600-700bhp+
Had mine to 160 funny enough and was great but the front does go light on a gt3 at that speed I felt

mm450exc

571 posts

208 months

Saturday 21st July 2012
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170mph in my 997 turbo feels fast! You do feel the speed. In an A8 you would not. But that's all down to the size/weight...

Callughan

6,313 posts

222 months

Saturday 21st July 2012
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Shouldn't feel hairy but is very different to how a BM or Merc feels as its relatively smaller and lighter. Make sure geo, tyres and wheel balance etc.. are ok. GPS and speedo were same for me.

911p

2,361 posts

210 months

Saturday 21st July 2012
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The GT3 saw a GPS verified 176mph (speedo showing 183, surprisingly accurate) one Sunday a few weeks ago. Dad commented that it felt amazingly solid and stable with no front end lightness at all; the driver of the 996 Turbo S we were following commented his felt quite light at the front, but still stable.

Both cars have fully sorted geo. The different models just have different characteristics, however you really shouldn't be getting any significant wheel wobble at any speed. Most likely a wheel balancing problem. If the front feels very light at speed perhaps you have a geometry issue, and it could even be down to some aerodynamic panels missing underneath.

Sy247

377 posts

224 months

Sunday 22nd July 2012
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Had my 996t up to 176 at brunters. Felt fast but stable no problems. On a public road, even an autobahn I would imahine it would feel a fair bit faster. Other traffic, crash barriers etc.

Get the suspension checked by centre gravity, parr, fearnsport or someone who knows what they are doing. Mine had done 40k and needed new coffin arms all round, rear diagonal arms, track rod end. Top mounts were wearing but servicable. Also make sure tyre pressures are 36/44 and you're on decent rubber

GC8

19,910 posts

220 months

Sunday 22nd July 2012
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Id echo the comments about geo. This is the most likely cause, in my opinion, on an otherwise well maintained and fresh car.

Pip1968

1,400 posts

234 months

Sunday 22nd July 2012
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I have to say that coming from a long line of BMWs I found my GT3 a little unnerving at 130+ but I am given to believe that these cars are meant to be a little like that. Do they not call it "A real driver's car" ie move involvement and feeling.

Personally I like the fact that it feels a little nose light and almost skittish and out of control bouncing around the road at speed. It certainly gets the hackles up.

Pip

TOV!E

2,016 posts

264 months

Sunday 22nd July 2012
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Terminator X said:
Doesn't sound right to me. My C2 should do 173mph and I'd expect it to when needed.

TX.
laughlaugh