S65

dexx · 02-28-2011, 11:50 PM

Sometimes I wonder, it would sound insane, less nascar.

aajami · 03-01-2011, 12:07 AM

Not sure about the production cost deltas between the two. It strikes me as being negligable, as the only major component difference is the shape of the crank and the lack of counterweights. But, I'm by no means an expert in this department...

That said, I think the primary reason for BMW going with a cross-plane crank design is because it produces less vibrations and is inherently more balanced than a flat-plane crank, which makes the car much more livable for its target audience.

At any rate, here's the P65-equipped (flat-plane crank) ALMS M3:

swamp2 · 03-01-2011, 03:31 AM

Cross plane has improved NVH (noise vibration and harshness) over the flat plane.

mkoesel · 03-01-2011, 08:33 AM

Some more good discussion can be found in past threads too:

http://www.google.com/search?q=site%...com+flat+plane

JCtx · 03-01-2011, 07:57 PM

Quote:

Originally Posted by GhostRideTheWhip

I don't think a flat plane crank wouldn't be cost effective.

It's a lot cheaper to produce man

. That's exactly how V8s started life back in the late 1800s. It was until the 1920s that advance in manufacturing techniques gave birth to the cross-plane crank. I definitely like the sound of the S65 better over the F430, even with an aftermarket exhaust (they sound like crap stock IMO).

CeeBoogie · 03-02-2011, 09:23 AM

Would it be possible to use a flat plane crank in the S65??? Thats what I would like to know!!!

Kyoshi71 · 03-02-2011, 09:36 AM

Quote:

Originally Posted by dexx

Sometimes I wonder, it would sound insane, less nascar.

So the engineers should design an engine around sound rather than function?
Ok

///My5UV · 03-02-2011, 10:18 AM

I think the biggest issue is packaging. Flat plane needs more width and less height, but I don't think they have any width to give in a front-engine car, unless you make the hood a couple feet longer :-)

JAJ · 03-02-2011, 10:56 AM

Quote:

Originally Posted by dexx

Sometimes I wonder, it would sound insane, less nascar.

The BMW Motorsport P65 race engine as derived from the S65 has a flat plane crank.

mkoesel · 03-02-2011, 11:01 AM

Quote:

Originally Posted by ///My5UV

I think the biggest issue is packaging. Flat plane needs more width and less height, but I don't think they have any width to give in a front-engine car, unless you make the hood a couple feet longer :-)

You are thinking of a horizontally opposed engine layout (often called a "boxer"). The thread is about a flat plane crank. It adds nothing to the dimensions of the engine; it just changes the shape of the crankshaft.

needspeed · 03-02-2011, 12:37 PM

Quote:

Originally Posted by elp_jc

It's a lot cheaper to produce man

. That's exactly how V8s started life back in the late 1800s. It was until the 1920s that advance in manufacturing techniques gave birth to the cross-plane crank. I definitely like the sound of the S65 better over the F430, even with an aftermarket exhaust (they sound like crap stock IMO).

Owning an F430 and an M3 I can tell you that the M3 sound is not close. I agree that the F-Car needs an aftermarket exhaust which I have. But nothing comes close to the F-Car sound IMO and many others........Steve

JCtx · 03-02-2011, 01:15 PM

Quote:

Originally Posted by needspeed

Owning an F430 and an M3 I can tell you that the M3 sound is not close.

A matter of opinion; I like the M3's more refined engine sound better

, but at the same time, nothing sounds like a Ferrari. I like the sound A LOT better from the inside than outside, however. Have the stock exhaust but with FabSpeed pipes (no valves) and tips, and it's too loud IMO, plus drones like hell with the top up ('06 F430 Spider here). Need to get to a rally to hear all aftermarket options, but read higher-pitched exhausts drone less. I see you also have the same handle at Fchat

. But they're TOTALLY different cars; don't mind the noise on the F-car, but I do on the M3 (stock exhaust here). Later.

///My5UV · 03-02-2011, 01:30 PM

Quote:

Originally Posted by mkoesel

You are thinking of a horizontally opposed engine layout (often called a "boxer"). The thread is about a flat plane crank. It adds nothing to the dimensions of the engine; it just changes the shape of the crankshaft.

Oops, yeah, I realized that later. My bad.

dexx · 03-02-2011, 08:53 PM

Quote:

Originally Posted by Kyoshi71

So the engineers should design an engine around sound rather than function?
Ok

LOL fanboism. Flat-plane performs better.. Why do you think race teams replace their crank with one?

Unequal exhaust pulses FTL....

dhoggm3 · 03-03-2011, 05:29 AM

Cost and NVH. More M3's than F430's are sold. I still wish my M3 had a FPC.

Cruise'n · 07-18-2023, 12:21 PM

Quote:

Originally Posted by mkoesel

You are thinking of a horizontally opposed engine layout (often called a "boxer"). The thread is about a flat plane crank. It adds nothing to the dimensions of the engine; it just changes the shape of the crankshaft.

His comment is correct. Flat plane crank are a smaller design as the sump is smaller and the engine can be lower, giving a lower centre of gravity
Packaging in small engine bays much easier.

Brandoch · 07-18-2023, 12:23 PM

Quote:

Originally Posted by Cruise'n

His comment is correct. Flat plane crank are a smaller design as the sump is smaller and the engine can be lower, giving a lower centre of gravity
Packaging in small engine bays much easier.

That was 12 years ago.

Cruise'n · 09-02-2023, 12:56 AM

But this the reason now or then?

But that's why the new X5 m60i S68 has now a flat plan crank.
The bonnet and front of the car is lower isn't it.

djsilverjohnson · 09-03-2023, 05:43 AM

The flat plane design has a different and more pronounced vibration signature. When Ford used it in the Mustang, several early production cars vibrated enough to break the oil cooler lines and catch fire. I read a long article about the FPC in the C8 Corvette and it stated that they put as much engineering into the motor mounts as they did into the engine. The C8 engine and transaxle mounts are designed to separate the engine vibration from the chassis, not to hold the engine still.

Cruise'n · 09-10-2023, 09:19 AM

Quote:

Originally Posted by djsilverjohnson

The flat plane design has a different and more pronounced vibration signature. When Ford used it in the Mustang, several early production cars vibrated enough to break the oil cooler lines and catch fire. I read a long article about the FPC in the C8 Corvette and it stated that they put as much engineering into the motor mounts as they did into the engine. The C8 engine and transaxle mounts are designed to separate the engine vibration from the chassis, not to hold the engine still.

Very interesting 🤔

The new S68 M60i models that replaces the old N63 M50i models.
Was surprised nobody has mentioned the engine being more course at all.
Presume BMW too have engineered the mounts to absorb the vibrations?

02-28-2011, 11:50 PM	#1
dexx Second Lieutenant 14 Rep 263 Posts Drives: 05 LGT w/AVO380, '11 M3 ZCP Join Date: Dec 2008 Location: MA iTrader: (0)	S65 - why no flat plane crankshaft? Sometimes I wonder, it would sound insane, less nascar. __________________ 2011 E90 M3 ZP2 ZCV ZCW ZCP (for teh fastAr) 2005 LGT, AVO380 Turbo, a zillion other mods, ECU tuning by me.
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03-01-2011, 12:07 AM	#2
aajami Brigadier General 432 Rep 4,567 Posts Drives: Space Gray '09 E92 M3 Join Date: Dec 2008 Location: Manhattan Beach, CA iTrader: (4)	Not sure about the production cost deltas between the two. It strikes me as being negligable, as the only major component difference is the shape of the crank and the lack of counterweights. But, I'm by no means an expert in this department... That said, I think the primary reason for BMW going with a cross-plane crank design is because it produces less vibrations and is inherently more balanced than a flat-plane crank, which makes the car much more livable for its target audience. At any rate, here's the P65-equipped (flat-plane crank) ALMS M3: __________________ '09 E92 M3: Space Gray, Black, Carbon Leather \| ZTP 2MK ZPP 2MT 6FL \| link 1 / link 2 Mods: M Performance exhaust \| ZCP retrofit \| Euro airbox \| GTS DCT flash \| JPN 240 ECU flash \| Euro LCI taillights \| CRT lip \| OEM alarm retrofit \| Space Gray bumper plugs \| BMW Performance: Mk. II spoiler / Mk. II non-electronic steering wheel / mirror caps / front grilles / side gills / intake louvers / emblem
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03-01-2011, 03:31 AM	#3
swamp2 Lieutenant General 611 Rep 10,407 Posts Drives: E92 M3 Join Date: Sep 2006 Location: San Diego, CA USA iTrader: (3)	Cross plane has improved NVH (noise vibration and harshness) over the flat plane. __________________ E92 M3 \| Space Gray on Fox Red \| M-DCT \| CF Roof \| RAC RG63 Wheels \| Brembo 380mm BBK \| \| Vorsteiner Ti Exhaust \| Matte Black Grilles/Side Gills/Rear Emblem/Mirrors \| \| Alekshop Back up Camera \| GP Thunders \| BMW Aluminum Pedals \| Elite Angels \| \| XPEL Full Front Wrap \| Hardwired V1 \| Interior Xenon Light Kit \|
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03-01-2011, 08:33 AM	#4
mkoesel Moderator 7512 Rep 19,368 Posts Drives: No BMW for now Join Date: Jun 2006 Location: Canton, MI iTrader: (1)	Some more good discussion can be found in past threads too: http://www.google.com/search?q=site%...com+flat+plane
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03-02-2011, 09:23 AM	#6
CeeBoogie Private First Class 16 Rep 109 Posts Drives: E46 M3 Join Date: May 2008 Location: Long Island NY iTrader: (0)	Would it be possible to use a flat plane crank in the S65??? Thats what I would like to know!!!
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03-02-2011, 10:18 AM	#8
///My5UV Lurker 78 Rep 812 Posts Drives: YMB F80, SS E90 Join Date: Nov 2010 Location: Austin iTrader: (0)	I think the biggest issue is packaging. Flat plane needs more width and less height, but I don't think they have any width to give in a front-engine car, unless you make the hood a couple feet longer :-)
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03-03-2011, 05:29 AM	#15
dhoggm3 Major 269 Rep 1,282 Posts Drives: 850i C, Gated R8 5.2, E63 Join Date: Jul 2007 Location: Central PA iTrader: (1)	Cost and NVH. More M3's than F430's are sold. I still wish my M3 had a FPC. __________________ M850i Vert with RaceChip E46 M3, Euro Headers, Rasp Pipe, Kassel Tune Alpina B8, zero performance mods
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09-02-2023, 12:56 AM	#18
Cruise'n Private First Class 71 Rep 185 Posts Drives: X5 M60i Join Date: Oct 2015 Location: Right Here iTrader: (0) Garage List 2024 BMW [0.00]	But this the reason now or then? But that's why the new X5 m60i S68 has now a flat plan crank. The bonnet and front of the car is lower isn't it.
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09-03-2023, 05:43 AM	#19
djsilverjohnson Private First Class 116 Rep 159 Posts Drives: 2013 E93 M3 Join Date: Feb 2020 Location: Georgia iTrader: (0)	The flat plane design has a different and more pronounced vibration signature. When Ford used it in the Mustang, several early production cars vibrated enough to break the oil cooler lines and catch fire. I read a long article about the FPC in the C8 Corvette and it stated that they put as much engineering into the motor mounts as they did into the engine. The C8 engine and transaxle mounts are designed to separate the engine vibration from the chassis, not to hold the engine still.
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