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Old 08-12-2004 | 12:03 AM
  #31  
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Jim R.
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Jason,
If I stand on it above 4000 rpm in first, the tires will spin until I shift to second. From a dead stop, a little clutch slippage ~2000 rpm will spin the tires. I don't do this often, but it is fun occasionally. My rear tires are 255/40/17 bridgestone re 730, which are not the stickiest. A stickier tire would not spin so easily. I think Andy or Tim could easily solve all of our "excessive traction" issues.

Jim R.
Old 08-12-2004 | 12:48 AM
  #32  
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On a properly working auto trans you either have to give significant throttle upon take off to get it to take off in first or simply shift down to 2nd while you are at a dead stop. That will pre select first gear and it will force the tranny to start in first gear even if you have already pushed it back to "D".
It's not real fast off the line, but there are still not many cars to match your acceleration once you are moving.
I have a good friend with an M3 and he has never made any ground on my car on the highway. Last time we went somewhere he said "he was in the wrong gear...", yea right, I made about two car length on him pulling from about 30 - 90 MPH out off a toll booth.
I drove along a fellow Rennlist memeber a while ago and he gained about two car length on me taking off from a dead stop to about 70MPH in his '91 GT. Correct me if I am wrong Cameron...
So I would say the GT is quite a bit faster.
regards,
Sab.
Old 08-12-2004 | 01:17 PM
  #33  
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Yea, two car lenghts sounds about right. Provided the car is pulling a 30 ft cabin cruiser!



Just kidding. Trying to get you into a 5-speed, Sab.



.....Cameron
'91 Euro GT
Old 08-12-2004 | 06:14 PM
  #34  
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I would say that even a standard Mustang is pretty good from a standing start (check my signature!) and up to 50 mph there is not much difference in the feel between the mustang and the 928 - after that speed then you really feel a difference and over 100 mph the 928 really gets on song - there is very little that will keep up with me in the 928 when accelerating from 100 mph on the autobahn.
BTW, do you realise if these guys who say speed kills and every 5 mph increment doubles your risk of an accident are correct then it is a miracle that the F1 drivers survive the first lap - they are up to the level of a billion to 1 chance of an accident.

Now I just know that Jim will flame me
Old 08-12-2004 | 07:31 PM
  #35  
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Take your car to intersport and have it Dyno'd. A significant number of us dyno'd our cars last year at the 928 frenzy. If you post your results, we will all be able to quickly confirm how your car is performing.

Also, if you can fnd someone to run the Bosch Hammer, a bad Knock sensor, bad Hall sensor all can retard the timing
Old 08-13-2004 | 06:42 PM
  #36  
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I was thinking Autosport Systems in Tyson's - they did a good job on my timing belt - I don't know if they have a dyno though. Where is Intersport located? A dyno is a great idea...

Bill
Old 08-13-2004 | 07:06 PM
  #37  
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Re the throttle cable adjustment. Here is a simplistic, quick explanation.
Cameron (and the follow up from Garth): Thank you very much! I will investigate and adjust as necessary tonight. (I'm hoping I can find a few extra horses!)
Old 08-13-2004 | 09:24 PM
  #38  
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What kind of fuel are you using? Take it out and watch your temp. guage - then fill it with high octane and feel if you get any advance and watch the guage again for slightly cooler head temp.

Good point also about the Al Holbert salt flat 187 mile an hour ring and pinions - you are not winning burnouts with US muscle cars easily.

Old 08-13-2004 | 10:21 PM
  #39  
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Talking Age not a factor

My '83 still posts exactly what was in the manual, 0-60 in 6.7 +/- .1 sec even after 21 years. My G-Tech shows an initial acceleration of .73 G's, with a low 14 sec 1/4 mile. All this, and it still passes the tough Houston emissions check (measured on a chassis dyno) with flying colors ( <10% of allowed values).
Porsche built a machine, and a heck of a good one! The tough part is keeping the more advanced ones running. I have seen a lot of comments about the 4 valve 928's in recent months and one thing is for certain, they have many more parts required to make the additional HP. Sometimes they work well, but most often there is a lot of headaches and troubleshooting required. If you like that sort of thing please enjoy...
I love my 16V engine and would not trade it for the additional HP, especially not for one of the GTS's which should almost be considered diesels (burning a quart of oil per 600 miles)...

Hey I'm allowed to ramble aren't I ???


Old 08-14-2004 | 06:24 AM
  #40  
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0-60 in 9 seconds... something is definitely not correct. what additional info will the dyno offer? if you could find a mechanic who knows the 928 they could probably help more, but i echo the ideas allready presented. to start with the simple things - throttle cable and petrol treatment - plugs, distributors and leads etc.
Old 08-14-2004 | 10:53 AM
  #41  
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Bill . . I just got my car from the trans shop yesterday and before I brought it home I went for a test drive. I wasn't happy with the way it shifted. Floored it shifted @4200 rpm's. I told the boss that it feels weak & I want redline. We adjusted it a couple of times & now all I can say is holy moley. To start out in first, down shift your shifter to 2nd or at a stop, while holding the brake hit the pedal to the floor real fast. That will start the car off in first. Shifting into low is much easier. You will notice a tremendous difference.

HTH
Old 08-14-2004 | 01:01 PM
  #42  
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Originally Posted by bgrabner
I just replaced the plugs and fuel filter with no change in performance. The idle is a little rough, but that is a pretty recent development, and the car has always performed like this.
That reminds me of my '87 S4 automatic, which developed a distinct lack of power, bad enough that it would upshift early. The spark plug wires were old and cracked, so brittle they made a pile of crumbles when I replaced them. After replacing the plug wires, the car perked right back up, staying in gear until red line. Just a thought...




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