motoring|underground  
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read Blog

Safety & Race Preparation Roll cages, harnesses, seats, weight reduction, etc. Anything pertaining to taking your car to the highest level of performance.

Go Back   motoring|underground > On the Lifts > Safety & Race Preparation
Reply
 
Thread Tools
  #31  
Old 07-09-2008, 03:53 AM
brownMINI brownMINI is offline
Y Rated - 186 mph
 
Join Date: Apr 2006
Location: VT
Posts: 1,885
Default

It would probably be more helpful if I had a "before" weight, but I weighed my Cooper at the track yesterday...

It's a 2003 Cooper with a sunroof. Rear seats and rear interior is gone. Front seats replaced with race seats. Semi-light 15" wheels. No A/C. No radio / rear speakers. Miata battery placed in the back. Foglights gone. Rear wiper delete. No spare. Emptied for the track. No driver / passenger. 1/2 tank of gas.

Weighed on NASCAR tech inspection scales.

Total: 2421 lbs
Left front: 717 lbs
Right front: 744 lbs
Left rear: 475 lbs
Right rear: 485 lbs

Front / rear distribution: 60.3/39.7 (better than I expected)

left / right distribution: 49.2/50.8 (I don't know enough to know if this is close enough to 50/50 or not)

cross-weight (RF-LR / LF-RR): 50.3/49.7 - looks close to 50/50... and adding me to the drivers seat would bring it closer, right?

I'm such a corner weight / car setup newb.
__________________
98 hp at the wheels
Reply With Quote
  #32  
Old 07-13-2008, 03:23 AM
Konstantinos's Avatar
Konstantinos Konstantinos is offline
Y Rated - 186 mph
 
Join Date: Nov 2007
Location: Norwalk, CT
Posts: 4,866
Send a message via AIM to Konstantinos
Default

This makes me wonder.... How can we remove more weight from the front to get closer to a 50/50. Furthermore, most of us have A/C, so that adds weight in front too. What can be taken out? What parts can be replaced for lightweight parts?

Also, yes, adding the driver evens out the MINI's weight distribution. It was engineered that way on purpose!!
__________________
The statement below is true
The statement above is false
Reply With Quote
  #33  
Old 07-13-2008, 10:45 PM
JIMEK's Avatar
JIMEK JIMEK is offline
Y Rated - 186 mph
 
Join Date: Apr 2007
Posts: 5,773
Default

AC is only like 5kg or 10pounds. if you have the stock seat - taking out the passanger seat is the easiest/best result.
Reply With Quote
  #34  
Old 07-14-2008, 03:40 AM
Konstantinos's Avatar
Konstantinos Konstantinos is offline
Y Rated - 186 mph
 
Join Date: Nov 2007
Location: Norwalk, CT
Posts: 4,866
Send a message via AIM to Konstantinos
Default

That's it? There must be more things that can be reduced inside the engine. For example, a lightened flywheel, light weight internals, etc etc etc
__________________
The statement below is true
The statement above is false
Reply With Quote
  #35  
Old 07-14-2008, 11:45 AM
brownMINI brownMINI is offline
Y Rated - 186 mph
 
Join Date: Apr 2006
Location: VT
Posts: 1,885
Default

In the engine bay...

Battery (for a Cooper or R56), flywheel, A/C, windshield washer reservoir, hood liner, plastic shrouds on firewall, hood latches, 2 wipers -> 1 wiper, remove some of the metal bumper support...

I already have most of that. I've still got both wipers and the washer fluid bottle. There's more metal that could be taken off the bumper mount too.
__________________
98 hp at the wheels
Reply With Quote
  #36  
Old 11-20-2008, 06:50 AM
MINI_chili MINI_chili is offline
N Rated - 87 mph
 
Join Date: Oct 2008
Posts: 5
Default

this is kinda late, but...
Quote:
Originally Posted by brownMINI View Post
Running low on fuel is worth a few pounds.

All of this probably won't really matter much, though. My last autocross, for the morning session I had the fuel light on and was down to 20 miles left on the computer. During lunch, I filled up. In the afternoon, I went over a second faster.

Until you're driving close to perfectly, you'll gain more speed by driving better than by losing a few pounds off the car.
the extra fuel probably made the weight balance better

Quote:
Originally Posted by JIMEK View Post
arent the back seats like a couple of pounds?
they seem like a lil bit of sponge...
the bottom of the seats weight next to nothing, but the backs have to be close to 15 lbs each, if not more
Reply With Quote
  #37  
Old 11-20-2008, 05:31 PM
Konstantinos's Avatar
Konstantinos Konstantinos is offline
Y Rated - 186 mph
 
Join Date: Nov 2007
Location: Norwalk, CT
Posts: 4,866
Send a message via AIM to Konstantinos
Default

Quote:
Originally Posted by MINI_chili View Post
the extra fuel probably made the weight balance better
I agree. Balancing the weight of gas in the rear with a front-engine car is probably going to help you handle better, despite the added weight.
__________________
The statement below is true
The statement above is false
Reply With Quote
  #38  
Old 07-30-2010, 03:28 PM
Bilbo Baggins Bilbo Baggins is offline
N Rated - 87 mph
 
Join Date: Dec 2005
Location: Shire, Middle Earth
Posts: 16
Default

Something overlooked here is un-sprung weight. Going with the lightest 15" wheels would save a lot of weight located in a very bad spot. Comparing un-sprung to sprung weight there is either a 6 to 1 or 7 to 1 advantage, ie for every 1 lb of un-sprung weight removed would be like taking off 6 lbs of sprung weight.


The gains would be better handling, shorter stops, and quicker acceleration. A side benefit is that a smaller diameter tire could be fitted, without sacrificing tread width, yielding a lower overall gear ratio also improving acceleration and drive out of the corners. The smaller overall diameter tire effectively lowers the center of gravity of the car, improving cornering, without reducing the amount of suspension travel.
__________________
MINI - the most fun you can have with your trousers/pants/panties on!

Last edited by Bilbo Baggins; 07-30-2010 at 03:35 PM..
Reply With Quote
  #39  
Old 07-30-2010, 05:07 PM
Pobsey Pobsey is offline
μ
 
Join Date: May 2006
Location: Staffordshire, England
Posts: 2,925
Default

I think the track day has finished now
__________________
Click the image to open in full size.
M|U, the barometer of MINI cool
Reply With Quote
  #40  
Old 07-30-2010, 08:24 PM
JIMEK's Avatar
JIMEK JIMEK is offline
Y Rated - 186 mph
 
Join Date: Apr 2007
Posts: 5,773
Default

hahahha
unsprung weight is a must but kinda hard to fix a day before a track day
Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


CURRENT MOON

All times are GMT. The time now is 07:03 PM.
Powered by vBulletin® Version 3.8.1
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
2005 motoring|underground, all rights reserved.