MK-I MK-II MK-III MK-IV GULF MIRAGE J-CAR LOLA
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06-30-08, 10:53 PM
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#1 (permalink)
| | MK -IV J6 10 tenths 
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24  | P 4/5 in wind tunnel
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07-01-08, 12:59 AM
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#2 (permalink)
| | Doug68 2 Tenths 
Join Date: Jul 2007 Location: Perth, WA
Posts: 200
Rep Power: 4 | Re: P 4/5 in wind tunnel
Three things...
1. Much too Short. 
2. I'd love to see the results. 
3. How cool is it when your job involves taking a file an wailing on such a creation! (I'd actually imaged the shape was created by taking a solid block of CF and rubbing down with olive oil & naked Italian super models but I digress). | |
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07-01-08, 02:22 AM
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#3 (permalink)
| | dazza67 Rookie
Join Date: Oct 2007 Location: Australia
Posts: 13
Rep Power: 2 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by Doug68  I'd actually imaged the shape was created by taking a solid block of CF and rubbing down with olive oil & naked Italian super models but I digress. | Damn, another of my dreams shattered | |
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07-01-08, 12:04 PM
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#4 (permalink)
| | MK -IV J6 10 tenths
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by Doug68 Three things...
1. Much too Short.
2. I'd love to see the results.
3. How cool is it when your job involves taking a file an wailing on such a creation! (I'd actually imaged the shape was created by taking a solid block of CF and rubbing down with olive oil & naked Italian super models but I digress). | 
We were going for several things. Firstly we wanted to maximise engine/oil/brake cooling without adding excessive drag or disrupting the air. We also wanted to tune out wake turbulence. Next we wanted to balance the down force and add some without over stressing suspension for the street. In the end we did pretty well. We lowered the Cx vs the Enzo, increased downforce, and was able to make the nose more suitable for the street while maintaining downforce. | |
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07-04-08, 01:21 AM
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#5 (permalink)
| | gt40fran Sponsoring Vendor
Join Date: Sep 2001 Location: Manufacturer of GT40: Michigan,USA
Posts: 3,098
| Re: P 4/5 in wind tunnel
Jim,
what was you eventual lift vs drag coeffiecient?..and your overall DF?
I am running some high end CFD on the SL-C at the moment so your benchmark would be informative..
PM would be great..
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07-04-08, 10:23 AM
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#6 (permalink)
| | Big-Foot Gold Supporter
Join Date: Jan 2007 Location: Minneapolis, MN GT40: RCR40 - #45
Posts: 1,526
| Re: P 4/5 in wind tunnel
Is this the correct link? YouTube - Ferrari P 4/5 in wind tunnel
What a beautiful car!!! | |
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07-04-08, 11:55 AM
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#7 (permalink)
| | Doug68 2 Tenths
Join Date: Jul 2007 Location: Perth, WA
Posts: 200
Rep Power: 4 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by gt40fran PM would be great.. | Not fair!  | |
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07-05-08, 11:16 PM
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#8 (permalink)
| | MK -IV J6 10 tenths
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by gt40fran Jim,
what was you eventual lift vs drag coeffiecient?..and your overall DF?
I am running some high end CFD on the SL-C at the moment so your benchmark would be informative..
PM would be great.. | Cx was about .3 We were making about 1000 lbs of downforce at 150 mph. We could have made more but didn't want to increase springs for the street. At 200 on the banking we put the rt rear fender into the tire compressing the body about 2 inches.
The springs are fine for the street but you'd want more for racing.
Last edited by MK -IV J6; 07-05-08 at 11:22 PM.
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07-10-08, 11:54 AM
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#9 (permalink)
| | MK -IV J6 10 tenths
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24 | Re: P 4/5 in wind tunnel
Pop Star... | |
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07-10-08, 03:06 PM
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#10 (permalink)
| | ckouba 6 Tenths
Join Date: Feb 2004 Location: Phoenix, AZ, USA GT40: RCR40-31
Posts: 616
Rep Power: 11 | Re: P 4/5 in wind tunnel
So THAT's where you got it painted. Maybe if I ever finish my body prep I'll send it there to shoot it. | |
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07-10-08, 03:30 PM
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#11 (permalink)
| | MK -IV J6 10 tenths
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by ckouba So THAT's where you got it painted. Maybe if I ever finish my body prep I'll send it there to shoot it. | :0 | |
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07-13-08, 11:12 AM
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#12 (permalink)
| | MK -IV J6 10 tenths
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24 | Re: P 4/5 in wind tunnel
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07-13-08, 01:14 PM
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#13 (permalink)
| | 60-61 Lifetime Premier Supporter
Join Date: Oct 2006 Location: Colorado, USA GT40: Superformance
Posts: 214
Rep Power: 5 | Re: P 4/5 in wind tunnel
Jim-
You're right. We protect history and pass it on. In the end, we don't own it. It's always fun to see this peace of history.
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07-14-08, 08:55 PM
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#14 (permalink)
| | 7 Tenths
Join Date: Dec 2002 GT40: USA
Posts: 716
Rep Power: 17 | Re: P 4/5 in wind tunnel
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07-14-08, 11:03 PM
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#15 (permalink)
| | 550spydr 2 Tenths
Join Date: May 2006 Location: Millbrook,NY GT40: GTD
Posts: 208
Rep Power: 5 | Re: P 4/5 in wind tunnel
Thanks!!
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07-15-08, 01:34 AM
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#16 (permalink)
| | Doug68 2 Tenths
Join Date: Jul 2007 Location: Perth, WA
Posts: 200
Rep Power: 4 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by MK -IV J6 Cx was about .3 We were making about 1000 lbs of downforce at 150 mph. We could have made more but didn't want to increase springs for the street. At 200 on the banking we put the rt rear fender into the tire compressing the body about 2 inches.
The springs are fine for the street but you'd want more for racing. |
Wow I think those are good numbers considering the lack of wings and other visually obtrusive aero devices.
I read (and need to re-read) an article in Bernoulli on the aero development of the FXX which had also the aim of bettering the Enzo drag and down force wise. It's interesting to see the completely different approaches in shape to achieving the close to the same goal. | |
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07-15-08, 11:48 AM
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#17 (permalink)
| | MK -IV J6 10 tenths
Join Date: Mar 2002 GT40: NYC,USA
Posts: 1,590
Rep Power: 24 | Re: P 4/5 in wind tunnel
Quote:
Originally Posted by Doug68 Wow I think those are good numbers considering the lack of wings and other visually obtrusive aero devices.
I read (and need to re-read) an article in Bernoulli on the aero development of the FXX which had also the aim of bettering the Enzo drag and down force wise. It's interesting to see the completely different approaches in shape to achieving the close to the same goal. |
A big part of reducing drag was decreasing inlets and enlarging exits. The Enzo had too little exit so at high speed the air flow reverted backwards out of the inlets.
P 4/5 does have a large front canard and a larger rear spoiler which raises at speed. We had to beef up the spoiler mechanism to take the added load.
The high exhausts also back fill the hole left by the cockpit and the mirrors are aero devices which trim the wake vortexs.
Best | |
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07-15-08, 07:58 PM
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#18 (permalink)
| | kenshiro8 I Have No Life 
Join Date: Jul 2004 Location: Milano,Italy GT40: Fujimi 1/24
Posts: 2,335
Rep Power: 30 | Re: P 4/5 in wind tunnel
really one of the nicest one-off ever seen...
Will be hard for sheriff charger to stop u all
bellissima Jim..bravo.
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