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trunk spoiler effects on performance

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Old Aug 21, 2010 | 05:14 AM
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trunk spoiler effects on performance

I was under the impression that C-class trunk spoilers were so small that they were purely for aesthetic purposes.

However I just installed one from JBspeed and during my first drive since installing it, I immediately felt that the rear was a lot heavier than usual and it just felt different on the road (bumps became more noticeable as well). It feels like I have to push harder to accelerate now than before, which consequently seems to increase gas mileage.

I'm amazed that such a small addition can change so much and don't know if it's necessarily a good thing. Does anyone else have a similar experience or do most of you not notice anything after adding it?
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Old Aug 21, 2010 | 07:03 AM
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Lol that's funny
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Old Aug 21, 2010 | 07:54 AM
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Must have been your imagination.
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Old Aug 21, 2010 | 08:47 AM
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Probably the same effect as washing, detailing and filling up with gas...it just feels better but likley more in your mind than on the road.
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Old Aug 21, 2010 | 09:01 AM
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Yeah I thought it might just be my imagination too but the trip CPU shows me using more gas than usual and passengers who don't know about the spoiler commented that the ride seems harder than before. Not sure what to make of that on top of me feeling driving is different but. If the spoiler does nothing then I guess I can rule that out as a cause...

Last edited by lithium332; Aug 21, 2010 at 09:03 AM. Reason: Clarity
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Old Aug 21, 2010 | 10:04 AM
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Gives you an excellent excuse to get your ecu tuned now
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Old Aug 21, 2010 | 10:12 AM
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You cannot be serious.
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Old Aug 21, 2010 | 01:31 PM
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Trunk Spoiler increase down force on the rear wheels, giving you more traction and stability at high speeds and it has nothing to do with your gas mileage increase.
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Old Aug 21, 2010 | 03:42 PM
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lol wow. turns out my friend left two bowling ***** in the trunk and removing them solved the problem. i just assumed it was the spoiler because that's the only thing i did to it and i've never installed one before. i guess next time i'm going to paint my callipers red for the 30 hp increase.
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Old Aug 21, 2010 | 03:45 PM
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Originally Posted by tanktube67
Trunk Spoiler increase down force on the rear wheels, giving you more traction and stability at high speeds and it has nothing to do with your gas mileage increase.
Without a doubt. Studied advanced fluid dynamics and spoilers work and are designed for both form and function.
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Old Aug 21, 2010 | 04:05 PM
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Originally Posted by lithium332
lol wow. turns out my friend left two bowling ***** in the trunk and removing them solved the problem. i just assumed it was the spoiler because that's the only thing i did to it and i've never installed one before. i guess next time i'm going to paint my callipers red for the 30 hp increase.
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Old Aug 21, 2010 | 04:57 PM
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Your friend left his ***** in your car's trunk? That could be misconstrued in so many ways...
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Old Aug 21, 2010 | 05:03 PM
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Originally Posted by Sathinas
Your friend left his ***** in your car's trunk? That could be misconstrued in so many ways...
I just knew someone would make such a comment hahaha. It had to be two ***** too.
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Old Aug 21, 2010 | 05:28 PM
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How heavy were his ***** that you felt a difference in the weight of the car??
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Old Aug 21, 2010 | 05:43 PM
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Originally Posted by dynomite05
How heavy were his ***** that you felt a difference in the weight of the car??

A standard 15 lb and a heavier 16 lb one. I also just refilled my tank from near empty recently so not sure if that added to it. When I refill gas the car usually feels more sluggish and heavy afterward but again, maybe my imagination is just running wild or I'm just hyper sensitive to minute changes.
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Old Aug 21, 2010 | 06:00 PM
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Damn, he has some big *****. Lol
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Old Aug 21, 2010 | 06:01 PM
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Originally Posted by lithium332
I was under the impression that C-class trunk spoilers were so small that they were purely for aesthetic purposes.

However I just installed one from JBspeed and during my first drive since installing it, I immediately felt that the rear was a lot heavier than usual and it just felt different on the road (bumps became more noticeable as well). It feels like I have to push harder to accelerate now than before, which consequently seems to increase gas mileage.

I'm amazed that such a small addition can change so much and don't know if it's necessarily a good thing. Does anyone else have a similar experience or do most of you not notice anything after adding it?
I just got my spoiler from JBSpeed yesterday, but have not installed it yet. I think I am going to have my dealership install it for me because I dont trust myself with the installation.........one slip and I'm screwed.

What did you think of the color match to your car? Does it match pretty good? What color is your car?

I got the roof spoiler and the AMG trunk spoiler from them at the same time.
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Old Aug 21, 2010 | 06:40 PM
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Don't need a spoiler because the aero is so good on the W204. I've done at least 2000km at 240+ kph and the car is totally planted.

Cosmetically, I like either look.
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Old Aug 21, 2010 | 09:52 PM
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I've got my rear spoiler from them and the colour match very very well. No problems with me with the install and quality of the product at all. Mine is a palladium silver. I'll be getting a roof spoiler from JBSpeed soon as well. Do post up pics after you installed them.

Originally Posted by johnlk25
I just got my spoiler from JBSpeed yesterday, but have not installed it yet. I think I am going to have my dealership install it for me because I dont trust myself with the installation.........one slip and I'm screwed.

What did you think of the color match to your car? Does it match pretty good? What color is your car?

I got the roof spoiler and the AMG trunk spoiler from them at the same time.
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Old Aug 21, 2010 | 10:33 PM
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Originally Posted by lithium332
Yeah I thought it might just be my imagination too but the trip CPU shows me using more gas than usual and passengers who don't know about the spoiler commented that the ride seems harder than before. Not sure what to make of that on top of me feeling driving is different but. If the spoiler does nothing then I guess I can rule that out as a cause...
So it seems 2 extra bowling ***** in the trunk actually increased MPG? I should throw some in the trunk

Edit: Whoops I read wrong. Was really imagining that one

Last edited by Samieee; Aug 21, 2010 at 10:35 PM.
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Old Aug 21, 2010 | 10:41 PM
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Originally Posted by tanktube67
Trunk Spoiler increase down force on the rear wheels, giving you more traction and stability at high speeds and it has nothing to do with your gas mileage increase.

The effects of the trunk spoiler will really on be felt at higher speeds and a slim trunk lip spoiler will barely have a effect.
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Old Aug 21, 2010 | 11:05 PM
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Wild imagination

Originally Posted by lithium332
lol wow. turns out my friend left two bowling ***** in the trunk and removing them solved the problem. i just assumed it was the spoiler because that's the only thing i did to it and i've never installed one before. i guess next time i'm going to paint my callipers red for the 30 hp increase.
Don't forget the AMG sign for another 25HP.
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Old Aug 21, 2010 | 11:08 PM
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A spoiler will produce more downforce than a pair of bowling ***** in the trunk.
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Old Aug 21, 2010 | 11:13 PM
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i think the ///amg sign is 50horsepower not 25.
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Old Aug 22, 2010 | 12:27 AM
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Originally Posted by C300Sport
Probably the same effect as washing, detailing and filling up with gas...it just feels better but likley more in your mind than on the road.
lol... so it's not just me then after washing my car and and refilling gas i felt that the my car runs smoother and faster.
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