handling difference with roof open

songxu · 06-06-2008

I feel that my 350 handles slightly better in sharp turns with the roof open. When with the roof closed, the car feels front heavy at sharp turns. Just wonder do you guys feel that way. I figure it is because with the roof in the trunk, the weight distribution of the car is more towards rare, therefore make it easier to turn. I am wondering if I put some heavy stuff in the trunk, I may suffer a little in acceration, but I can turn sharper?? Just wonder, just wonder.

sam · 06-07-2008

i have the same feels.i also feel the same way when you change your seat to the lowest and back

**richard_leeds** · 06-07-2008

Roof up would raise the centre of gravity, increasing roll?

IMHO ... its all in the mind, perhaps you are simply more aware of what is happening with the roof down?

**alroumi** · 06-07-2008

I am with the original poster on this one, I love the handling with the roof down.

**DansSlk** · 06-07-2008

I've never noticed it myself but i think the weight distibution is near 50/50 with the roof down and the CG is lower, makes sense it would handle ever so slightly better but it could be mind games also like Richard said.

Ynot · 06-07-2008

I think it's mind games, when I autcrossed it a few years ago, I had better times with the roof up, the car seem more balance, I got faster times, that seems to contradict logic. When I had the roof down, it was more tail happy, slower times but much more fun. I think with the roof down, you are more aware of your surroundings, you don't push as hard, you don't have as much confidence with the roof up. NASA doesn't allow you to track with the roof down w/o a roll cage so I can't compare, one of these days I will go on an open track day and drive it with the top down to compare.

**SLKDawg** · 06-07-2008

Absolutely bc your head has more room to lean out of the car so you are able to put more weight towards the inside of the turn!!!

**alroumi** · 06-08-2008

Quote:

Originally Posted by SLKDawg

Absolutely bc your head has more room to lean out of the car so you are able to put more weight towards the inside of the turn!!!

, Thanks I needed that.

**Dolebludger** · 06-09-2008

I must respectfully disagree with the "mind game" theory. I think is is the lowering of the Center of Gravity (CG). When lowering the CG, a little can go a longer way than you might think. Hint: not everybody who lowers their car just a little bit does it for looks!

But there is a trade-off here. With top down, your top speed will be lower due to increased aerodynamic drag. You'll also notice that your acceleration also suffers in the higher speed ranges with top down

songxu · 06-10-2008

I believe also it is not mind game. The front heavyness of the car is obvious with the top closed at very sharp turns at slow speed, such as "U" turn, or 90degree into a side street at lower speed, with the top open, the car is much willing and able to make very sharp turns. Please guys, try this at a street with no people and drive at around 30mph, make a sharp 90 degree turn, without braking.

ssss

**xopher** · 08-04-2008

I weighed my SLK55 today on a scale that weighs the axles independently. The scale has 20 pound resolution and is calibrated. I first weighed it with the top up, then again with the top down. I had roughly 5/8 tank of gas with nothing else in the car other than what came with it. It's has the 030 package, so there is no spare tire.

Top Up:
1860 lbs front
1580 lbs rear

Top Down:
1840 lbs front
1600 lbs rear

So considering the scale reads in 20 pound increments, I can say there is between 1 and 39 pounds shifted to the rear with the top down. I'll take some standard weights next time to measure the shift to within a couple pounds. Either way, I thought the weight distribution was more balanced than that.

**ir-ops** · 08-05-2008

mind games or not, top down ride is awesome, although i have not pushed mine to any extremes yet (well, yes, you can push a 200k to certain extremes), but it definitely seems to handle better when the top is down...

best
ir-ops

06-06-2008	#1 (permalink)
songxu SLK World Member Join Date: May 2007 Location: Detroit Vehicle: 2005 SLK 350, 6 speed M Other Toys: BMW 330xi Posts: 23 Country: Thanks: 0 Thanked 1 Time in 1 Post	handling difference with roof open I feel that my 350 handles slightly better in sharp turns with the roof open. When with the roof closed, the car feels front heavy at sharp turns. Just wonder do you guys feel that way. I figure it is because with the roof in the trunk, the weight distribution of the car is more towards rare, therefore make it easier to turn. I am wondering if I put some heavy stuff in the trunk, I may suffer a little in acceration, but I can turn sharper?? Just wonder, just wonder.

06-07-2008	#4 (permalink)
alroumi Moderator Join Date: Jun 2006 Location: Kuwait City, Kuwait Vehicle: 2006 Kleemann Designo Mocha Black SLK55 AMG Other Toys: 2007 Ebony Jaguar XKR Coupe' and 06 Black Cayenne S Posts: 6,288 Country: Thanks: 298 Thanked 233 Times in 147 Posts	I am with the original poster on this one, I love the handling with the roof down. __________________ 06 Kleemann Designo Mocha Black SLK55 AMG 06 Porsche Cayenne S 07 Jaguar XKR Coupe' I use the Torque and keep the HP for my Steak Sauce!

06-07-2008	#5 (permalink)
DansSlk Dude Join Date: Jun 2006 Location: Wales Vehicle: 05 B55S (Brabus 6.1 S) Posts: 6,797 Country: Thanks: 96 Thanked 227 Times in 179 Posts	I've never noticed it myself but i think the weight distibution is near 50/50 with the roof down and the CG is lower, makes sense it would handle ever so slightly better but it could be mind games also like Richard said. __________________ One thing you will learn with German cars - If it's simple it ain't happening.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Would you like to upgrade the handling of your SLK350/280? Selling my AMG suspension!	Addicted2Speed	SLK R171 General Discussion	4	03-10-2008 12:43 PM
Handling the holidays.	Corkscrew	Off Topic	6	12-10-2007 11:45 PM
Suspension/Handling advice...	B4TM4N	Performance MODS for the R171	11	11-15-2007 02:49 PM
SLK280/SLK350 Difference	Gayle280	SLK R171 General Discussion	27	10-08-2006 11:53 PM
Prototype MB with a significant difference	easty	Off Topic	14	08-09-2006 04:04 AM

06-07-2008	#2 (permalink)
sam SLK World Member Join Date: Jan 2008 Location: canada Vehicle: 2005slk350 Posts: 10 Country: Thanks: 0 Thanked 0 Times in 0 Posts	i have the same feels.i also feel the same way when you change your seat to the lowest and back

06-07-2008	#3 (permalink)
richard_leeds Elite SLK World Member Join Date: Sep 2007 Location: Leeds, UK Vehicle: 05 350 Posts: 203 Country: Thanks: 12 Thanked 10 Times in 7 Posts	Roof up would raise the centre of gravity, increasing roll? IMHO ... its all in the mind, perhaps you are simply more aware of what is happening with the roof down?

06-07-2008	#6 (permalink)
Ynot Founding Member Join Date: Jun 2006 Location: Colorado Vehicle: 06' MBZ SLK Posts: 2,795 Country: Thanks: 135 Thanked 35 Times in 30 Posts	I think it's mind games, when I autcrossed it a few years ago, I had better times with the roof up, the car seem more balance, I got faster times, that seems to contradict logic. When I had the roof down, it was more tail happy, slower times but much more fun. I think with the roof down, you are more aware of your surroundings, you don't push as hard, you don't have as much confidence with the roof up. NASA doesn't allow you to track with the roof down w/o a roll cage so I can't compare, one of these days I will go on an open track day and drive it with the top down to compare.

06-07-2008	#7 (permalink)
SLKDawg Senior SLK World Member Join Date: Jun 2007 Location: ATL Vehicle: 2005 SLK350 Posts: 101 Country: Thanks: 1 Thanked 15 Times in 4 Posts	Absolutely bc your head has more room to lean out of the car so you are able to put more weight towards the inside of the turn!!!

06-09-2008	#9 (permalink)
Dolebludger Elite SLK World Member Join Date: Feb 2008 Location: Yukon, OK Vehicle: '07 SLK 280; '04 C 320, '01 Honda S 2000, '98 Ford Ranger truck. Posts: 569 Country: Thanks: 40 Thanked 78 Times in 52 Posts	I must respectfully disagree with the "mind game" theory. I think is is the lowering of the Center of Gravity (CG). When lowering the CG, a little can go a longer way than you might think. Hint: not everybody who lowers their car just a little bit does it for looks! But there is a trade-off here. With top down, your top speed will be lower due to increased aerodynamic drag. You'll also notice that your acceleration also suffers in the higher speed ranges with top down

06-10-2008	#10 (permalink)
songxu SLK World Member Join Date: May 2007 Location: Detroit Vehicle: 2005 SLK 350, 6 speed M Other Toys: BMW 330xi Posts: 23 Country: Thanks: 0 Thanked 1 Time in 1 Post	I believe also it is not mind game. The front heavyness of the car is obvious with the top closed at very sharp turns at slow speed, such as "U" turn, or 90degree into a side street at lower speed, with the top open, the car is much willing and able to make very sharp turns. Please guys, try this at a street with no people and drive at around 30mph, make a sharp 90 degree turn, without braking. ssss

08-04-2008	#11 (permalink)
xopher SLK World Member Join Date: Dec 2007 Location: Whidbey Island, WA Vehicle: '06 SLK 55 with 030 package Posts: 12 Country: Thanks: 4 Thanked 3 Times in 2 Posts	I weighed my SLK55 today on a scale that weighs the axles independently. The scale has 20 pound resolution and is calibrated. I first weighed it with the top up, then again with the top down. I had roughly 5/8 tank of gas with nothing else in the car other than what came with it. It's has the 030 package, so there is no spare tire. Top Up: 1860 lbs front 1580 lbs rear Top Down: 1840 lbs front 1600 lbs rear So considering the scale reads in 20 pound increments, I can say there is between 1 and 39 pounds shifted to the rear with the top down. I'll take some standard weights next time to measure the shift to within a couple pounds. Either way, I thought the weight distribution was more balanced than that.

08-05-2008	#12 (permalink)
ir-ops Lifetime SLK World Member Join Date: Oct 2007 Location: Athens, Greece Vehicle: happily owning a 2008 black on black manual/sport r171 200k f/l since july 2008 Posts: 595 Country: Thanks: 142 Thanked 71 Times in 46 Posts	mind games or not, top down ride is awesome, although i have not pushed mine to any extremes yet (well, yes, you can push a 200k to certain extremes), but it definitely seems to handle better when the top is down... best ir-ops

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Sponsored Links

Sponsored Links

Sponsored Links

Sponsored Links