"type 2" rear diffuser: performance, or just cosmetic?

Skeptdoc · 08-08-2010, 10:20 PM

Greetings,

I am quite new to this "mods" thing, but have been considering a rear diffuser, specifically, the VRS type 2 style. I have seen promise of increased downforce, but no emperic evidence.

Since I got rid of the stock exhaust, the back end looks a little "empty", so I am considering filling it with the diffuser. However, I am having a little bit of a hard time justifying the cost and effort if it is ONLY cosmetic...

Any thoughts, experience, or evidence of performance improvement?

Thanks!

E90///M3` · 08-08-2010, 10:34 PM

that specific one is all cosmetic

FruitCake · 08-09-2010, 04:41 AM

pure cosmetic, there is only 1 or 2 diffusers that actually offer, and cost probably 10x the price of crapstiner

montreal red · 08-09-2010, 11:34 AM

the diffuser on the e92/e90 cars are pretty much only cosmetic. it does almost nothing for aerodynamics.

Kyoshi71 · 08-09-2010, 11:37 AM

Quote:

Originally Posted by Skeptdoc

I have seen promise of increased downforce, but no emperic evidence.

You'll probably have to hit 195mph before it does anything other than looks.

SV Concepts III · 08-09-2010, 12:14 PM

The Type II diffuser is pure aesthetics, no real downforce to be had from it.

m33 · 08-09-2010, 02:42 PM

What about the bootlid ? Does that help at high speeds ?

SV Concepts III · 08-09-2010, 03:28 PM

The bootlid does provide downforce as a larger spoiler would but the main benefit is weight savings over the stock piece.

Skeptdoc · 08-09-2010, 09:26 PM

Thanks for the info... probably will wait until I find one for a better price.

08-08-2010, 10:20 PM	#1
Skeptdoc New Member 4 Rep 18 Posts Drives: 2010 M3 -AW DCT Join Date: Mar 2010 Location: Seattle, WA iTrader: (0)	"type 2" rear diffuser: performance, or just cosmetic? Greetings, I am quite new to this "mods" thing, but have been considering a rear diffuser, specifically, the VRS type 2 style. I have seen promise of increased downforce, but no emperic evidence. Since I got rid of the stock exhaust, the back end looks a little "empty", so I am considering filling it with the diffuser. However, I am having a little bit of a hard time justifying the cost and effort if it is ONLY cosmetic... Any thoughts, experience, or evidence of performance improvement? Thanks!
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08-08-2010, 10:34 PM	#2
E90///M3` Major General 141 Rep 5,264 Posts Drives: 2008 E90M3 Join Date: Jan 2009 Location: Daly City -4- Work///Camarillo is Home iTrader: (3) Garage List 2008 BMW E90 M3 [7.60]	that specific one is all cosmetic __________________ - Jason P :Have: 08 E90M3, Varis VRS Front Lip, LS3, ESS Supercharger, Arqray Exhaust, Neez Wheels :Want: VRS Carbon GT Wing & Cooling Bonnet, LCI Taillights :Videos: EnvyRidesTV, GPR 1, GPR 2, GPR 3, ///MFEST
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08-09-2010, 04:41 AM	#3
FruitCake Banned 88 Rep 1,680 Posts Drives: '10 E92 M3 Join Date: Nov 2008 Location: Los Angeles iTrader: (19)	pure cosmetic, there is only 1 or 2 diffusers that actually offer, and cost probably 10x the price of crapstiner
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08-09-2010, 11:34 AM	#4
montreal red chris 278 Rep 12,144 Posts Drives: White Boat Join Date: Jun 2007 Location: Toronto iTrader: (31)	the diffuser on the e92/e90 cars are pretty much only cosmetic. it does almost nothing for aerodynamics. __________________ Current: 2013 F10 M5 & 2016 Mini JCW 2013 GLK350 (gone), 997.1 GT3RS (gone), 2009 WRX STI (gone), e92 M3 (gone)
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08-09-2010, 12:14 PM	#6
SV Concepts III Lieutenant General 375 Rep 17,017 Posts Drives: BMW Duh Join Date: Apr 2005 Location: Santa Clara iTrader: (13)	The Type II diffuser is pure aesthetics, no real downforce to be had from it.
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08-09-2010, 02:42 PM	#7
m33 Banned 115 Rep 2,682 Posts Drives: E92 VT650 MCB Individual Join Date: Dec 2008 Location: CT iTrader: (5)	What about the bootlid ? Does that help at high speeds ?
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08-09-2010, 03:28 PM	#8
SV Concepts III Lieutenant General 375 Rep 17,017 Posts Drives: BMW Duh Join Date: Apr 2005 Location: Santa Clara iTrader: (13)	The bootlid does provide downforce as a larger spoiler would but the main benefit is weight savings over the stock piece.
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08-09-2010, 09:26 PM	#9
Skeptdoc New Member 4 Rep 18 Posts Drives: 2010 M3 -AW DCT Join Date: Mar 2010 Location: Seattle, WA iTrader: (0)	Thanks for the info... probably will wait until I find one for a better price.
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