[wanofakind01]

hey guys, quick question. recently got priced for multiple items from sun motors*, one of which is the M rear diffuser. was wondering if the front splitter actually complements on air flow, or is it just aesthetics (i mean, it does look really cool)?

i already have clearance problems with the front bumper around here, wasn't really planning on it being lower.

*shout out to sun motors and their great pricing!

[overcoil]

BMW accessories online says they compliment one another.
You got to assume once hitting a certain speed with only one of the devices attached you could upset the handling.
Whether the 2-series is susceptible to being upset? It's a risk.

[jamiejimmydavies]

I was told by the M division of my dealership that the front splitter, rear diffuser & rear spoiler are functional. They do actually increase downforce so depending on how true this is, getting one and not the other could have a detrimental effect to the handling.

[wjones14]

I don't doubt the diffuser and splitter are functional, but at what speed? My gut tells me you would have to be well over 100 mph for there to be any appreciable aerodynamic difference.

I bought the rear diffuser strictly based on the looks. No offense to others who like it, but I personally did not care for the look of the stock lower bumper. I bought the M Performance Exhaust and Rear diffuser together as port-installed options. I like the look of the front splitter as well, but was concerned about everyday drivability, i.e. scraping things.

[qnet]

I have a dealer-installed front splitter but regular rear valance. I did a track weekend and didn't notice any adverse handling in my car. As a beginner track driver I wonder what how different it would have felt with the rear valence. I only got well over 100 mph on one straight-a-way.

[overcoil]

Originally Posted by qnet

I have a dealer-installed front splitter but regular rear valance. I did a track weekend and didn't notice any adverse handling in my car. As a beginner track driver I wonder what how different it would have felt with the rear valence. I only got well over 100 mph on one straight-a-way.

When you say valence you mean down low by the exhaust ?
Because I don't think any MSport or similar rear valence will suck the car down. I think the little wicker spoiler on the tip of the trunk might minimize rear turbulence and prevent lift.
As for aiding rear traction or road holding, 80 or higher in the wet, 130 or higher in the dry - those I guess are the thresholds for aiding tire bite or chassis stability. Then crosswinds or gas-mileage the bodywork add-ons might come into play.

[qnet]

Originally Posted by ScottSinger

When you say valence you mean down low by the exhaust ?
Because I don't think any MSport or similar rear valence will suck the car down. I think the little wicker spoiler on the tip of the trunk might minimize rear turbulence and prevent lift.
As for aiding rear traction or road holding, 80 or higher in the wet, 130 or higher in the dry - those I guess are the thresholds for aiding tire bite or chassis stability. Then crosswinds or gas-mileage the bodywork add-ons might come into play.

Yeah, that's what I meant I guess I just worded it like Dinan does when you're ordering their exhaust. Unless I'm misunderstanding them, I thought rear valance and diffuser were the same thing. Some of you were saying that having having one without the other may affect things, since I only have the front splitter, I thought it might. I honestly don't have the driving experience to tell the difference, but I do like the way the front splitter looks.

[walnuttea]

I too was wondering the same thing. You gotta imagine it doesn't play a massive difference in having 1 or both items. The only reason I say that is because they "recommend" installing both. If having only one of these were to create significant aerodynamic imbalance, then I'm sure BMW would "require" installing both or at least more strongly state that it would be dangerous in some way or another. Then again that's just a hunch! Always a good way to encourage people to buy both.

[wanofakind01]

Thanks guys, appreciate all the feedback!