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313 km/h video in a 951

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Old 09-20-2005, 01:16 PM
  #46  
sweanders
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Originally Posted by toddk911
My understading is the 951 gearing is the only limiting factor, not hp. In regards to 200.

Our 5th is sooo short. I know at highway speeds going from 4th to 5th only drops the revs by a few hundred. basically 4 speed with overdrive

A nice 6 speed would do the trick
I have done some calculations and 304 km/h should be possible at just under 7100 rpm's with some big diameter rubbers with the stock gearing.
Old 09-20-2005, 02:04 PM
  #47  
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My calcs from www.scirocco.org (gears link) are as follows:

Tire: 245/50r18
Final Drive: 3.38 (stock '86 turbo, European car as source)
5th Gear: 0.83 (stock '86 turbo, European car as source)
Engine rpm: 6800

320 km/h or 199mph. However I'm sure that due to centrifical forces the tire diameter must increase a few millimeters thus pushing you over the 200mph.

Now the trick would be to generate enough hp at 6800 rpm to overcome wind... what would that take??? 450hp?
Old 09-20-2005, 02:18 PM
  #48  
toddk911
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But who in here is able to run that high of revs with out rev limit?

I have GURU chips and still hit it at like 6,500, give or take.
Old 09-20-2005, 02:53 PM
  #49  
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I'm no expert here, but couldn't you run Stand Alone??? 6800 rpm isn't much for a 4 banger, I've run 7200+ in others, mind you they were smaller displacement (lighter pistons, less reciprocating mass, etc...)
Old 09-20-2005, 03:22 PM
  #50  
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dont forget the speedo is ALWAYS off. X 2
Old 09-20-2005, 03:32 PM
  #51  
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Originally Posted by Campeck
dont forget the speedo is ALWAYS off. X 2
Yes, that is why it can't be trusted. Neither can the tacho and not even a GPS is good enough. Only thing accurate enough is a stopwatch and multiple mile markers.

How do I know? Because I have been navigating for an average of 145 mph over 96 miles and we hit 144.976 mph which earned us second place in the 145 class..

Old 09-20-2005, 04:39 PM
  #52  
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look here to see the differencve between the 17 and 18 inch wheels on teh same car ( a tuned RS)

then you know what is the difference for a 16 and a 18 Inch wheel




and do not forget I have to slow down because of otehr cars otherwise the car would go even faster. Also the 30 mm higher in the rear creates much more downforce and I I also run minimum low in teh front and I use a front spliter. I think this alone reduce the top speed by about 20 km/h
3 mm higher in the front on a Gt3 cup car gives you 3 km/h more top speed

Konstantin
Old 09-20-2005, 04:54 PM
  #53  
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Sure, bypassing the stock systems of rev limit, fuel cut etc. is not the issue.

The issue is how many revs will a stock motor handle???

Rebuilt stock??

There are plenty of small street/stock motors out there running 7,8,9K rpms. But what lets those motrors do that and not ours???
Old 09-20-2005, 04:58 PM
  #54  
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WOW, I never would have guess wheel diameters would even affect accelleration times.

Is the difference linear?
Old 09-20-2005, 05:02 PM
  #55  
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Originally Posted by toddk911
The issue is how many revs will a stock motor handle???
7k, then you'll start seeing increased wear.

Originally Posted by toddk911
There are plenty of small street/stock motors out there running 7,8,9K rpms. But what lets those motrors do that and not ours???
Solid lifters and a better cam will allow the 944 to rev a decent bit higher, how much higher I couldnt tell you though, that'd be a question for one of our performance shops (944 Enhancement, Lindsey Racing, Speedforce, JME, etc)
Old 09-20-2005, 05:12 PM
  #56  
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More pictures!!
Old 09-20-2005, 06:49 PM
  #57  
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Originally Posted by MPD47
7k, then you'll start seeing increased wear.

not sure about the turbos (because it seems NO ONE can answer my question if turbo valve springs are stronger than the NA's.) but over 6,600rpm my valves start to float. (massive backfiring through intake)
Old 09-20-2005, 06:58 PM
  #58  
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I'm purely going off of some old topics I read last night. I personally have never run my car over 6500.
Old 09-20-2005, 07:58 PM
  #59  
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What these motor can rev to??? I haven't a clue.

Well if 6800rpm doesn't do it for you then at 6500 and a 285/50r18 you'll hit 200mph

But i think the point may be missed here, Konstantin mentioned he is running 285/18's pretty sure they're not 50 series, but he's also said he altered the gear ratios for top end. While this may be great for the Fatherland here in North America it doesn't make sence for public driving, sure an all out race machine could be driven to those extremes but it's not going to have stock motors, heads, valve springs or anything...

I was just throwing out some hypothetical numbers, being new to the p-car world I have no idea really what the rev limits are for a 2.5l four cylinder eight valve motor. What I know is you shift before the needle gets into the red

And yes I agree, More pictures/video's.

After reviewing the video the highest I saw the tach read was somewhere between 6700 and 6800 around 310kph but it's really hard to estimate from the sharp angle... and we all know how accurate stock gauges are... not to take anything away from Konstantin's run it's stil crazy fast!
Old 09-20-2005, 08:37 PM
  #60  
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Originally Posted by Campeck
not sure about the turbos (because it seems NO ONE can answer my question if turbo valve springs are stronger than the NA's.)
yes they are stronger. Much stronger than teh S2 opr 968 or even a Gt3 cup
They are 20% stronger than a Gt3 cup

we tested all of them so these are not numbers from a book or heard say etc.

Konstantin


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