New 4.0 RSR
07-15-2008, 08:19 PM
#46
Drifting
Ferrari will have to work harder and harder. Its tough to stay disappointed in Porsche... 
I heard it at the race from folks. I was hoping people here knew more about it.
From Porsche's website re: the ALMS race at Lime Rock:
"Three of the GT2 Porsches – the Werner/Westbook car, the Flying Lizard Johannes van Overbeek/Patrick Pilet Porsche – which qualified fifth, and the Bergmeister/Henzler Porsche, are all outfitted with a new 4.0 liter engine, which develops the same horsepower as the current 3.8 liter engine. The engine, still in its testing phase, is designed to improve drivability by widening the power band. "
From Porsche's website re: the ALMS race at Lime Rock:
"Three of the GT2 Porsches – the Werner/Westbook car, the Flying Lizard Johannes van Overbeek/Patrick Pilet Porsche – which qualified fifth, and the Bergmeister/Henzler Porsche, are all outfitted with a new 4.0 liter engine, which develops the same horsepower as the current 3.8 liter engine. The engine, still in its testing phase, is designed to improve drivability by widening the power band. "
07-15-2008, 08:26 PM
#47
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07-15-2008, 09:51 PM
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http://www.imsaracing.net/2008/alms/...201st%20ED.pdf
07-15-2008, 10:05 PM
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Effectively "banned", but not officially banned. If I recall correctly, the M3 GTRs could still run in 2002, but only with much smaller restrictors and/or much more weight. ...until the required number of streetgoing versions were produced and marketed in the required number of countries.
07-15-2008, 10:28 PM
#52
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Effectively "banned", but not officially banned. If I recall correctly, the M3 GTRs could still run in 2002, but only with much smaller restrictors and/or much more weight. ...until the required number of streetgoing versions were produced and marketed in the required number of countries.
I guess it depends what the definition of "is" is.
07-15-2008, 10:42 PM
#53
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Per regs, modification to bore is permitted (from the homologated car), subject to mandated restrictor size for the resulting displacement. The only limitation to the allowed increase in displacement (that I can find, anyway) is the 8 liter max allowed for the class.
http://www.imsaracing.net/2008/alms/...201st%20ED.pdf
http://www.imsaracing.net/2008/alms/...201st%20ED.pdf
Bore = 102.7mm in both 3.8 and 4.0
Stroke = 76.4mm in 3.8, and 80.4mm in 4.0
Restrictor = 29.5mm x 2 in 3.8, and 29.3mm x 2 in 4.0
So, I dunno. Perhaps I didn't read the rules close enough...
07-15-2008, 10:51 PM
#54
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07-15-2008, 10:51 PM
#55
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Ha!
07-16-2008, 01:13 AM
#56
Formula One Spin Doctor
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It make sense for Porsche to step up to a 4L displacement engine , it's the same size BMW will be using in the ALMS come 09. With current restrictor sizes the 3.8 and the 4L should have similar BHP. the difference with the larger displacement being in the TQ peak and the TQ spread over a broader range. It does appear there will be a 997 GT3 4L in the not too distant future as ALMS gave BMW 1 yr to put forth a production model , it is quite possible it will be the same for Porsche.
Based on the bore /Stroke listed below i would guess and say , the extra displacement came from an increase in both bore/Stroke with most of the increase coming from the stroke.
997/ 3.8L Engine Specs.
* Six-cylinder aluminium boxer engine, water-cooled
* 3,795 cc; stroke 76.4 mm (3.01"); bore 102.7 mm (4.05")
* max. output: 342 kW (465 bhp) at 8000 rpm
* max. torque 430 Nm (317 lb-ft) at 7250 rpm
* air restrictors 2 x 29.5 mm
* max. rpm: 9,400 rpm
* four valves per cylinder
* dry sump lubrication
* individual throttle butterflies
* central air intake
* electronic MS 4.0 engine management
* fuel injection
* required fuel quality: 98 octane RON Super Plus unleaded
BMW M3
video : http://www.youtube.com/watch?v=QDw9ab5_lwE
*4L V8 Engine
*BMW P65 Engine.
*Type: Eight cylinder, V-configuration
*Capacity: 3999 cc
*Bore x stroke: 92 x 75.2 mm
*Max. output: approx. 485 bhp
*Max. torque: approx. 500 Nm
*Cylinder block: Aluminium cylinder block construction with bed plate lower section
*Crankshaft: Steel crankshaft
*Pistons: Forged skirt pistons
*Conrods: High-performance steel
*Cylinder head: Aluminium DOHC (Double Over Head amshaft); four valves Cper cylinder
*Valve train: Four overhead chain-driven camshafts, valve actuation via rocker arms
*Intake system: Eight throttle valves, made of CRP with load-charge optimized ram tubes
*Fuel system: Single cylinder multi-point injection
*Lubrication: Dry sump lubrication
*Cooling: Water/air cooler and oil/water heat exchanger
*Engine management: BMW Motorsport ECU 408 with two high-performance micro- processors; Individual cylinder injection and ignition; BMW Motorsport Lambda Controller Pit speed limiter, Quick Shift function; Engine data memory system
*Energy management: Electric energy management and monitoring with BMW Motorsport POWER400 control unit, networking of all sensors and actuators through bus system
*Ignition coil: Eight high-performance pencil coils with integrated ignition drivers
07-16-2008, 09:13 AM
#58
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I would never have said it didn't make sense, I was just curious how you could just adopt a new engine mid-season. Further, I don't understand the homologation rules, anyway, because what car in Porsche's lineup runs 3.8s? Just the (now old) RSR, right?
07-16-2008, 12:13 PM
#60
Formula One Spin Doctor
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In the past , ALMS allowed BMW to run what was essential a prototype setup and gave them 1 yr to Homologate ( press info at the time ) BMW could not do so after 1 yr and the ALMS imposed penalties on the car to even the playing field , BMW then withdrew the car from competition. I'm assuming it is the same deal now being given to Porsche . who may or may
not make a production 4L special..
not make a production 4L special..
Last edited by A.Wayne; 07-16-2008 at 12:51 PM.
