Drag Racing Tech
Sponsored by:
Sponsored by:

Another scaling idea..

Thread Tools
 
Search this Thread
 
Old 09-19-2006, 02:05 PM
  #1  
8 Second Club
Thread Starter
iTrader: (4)
 
Tony Shepherd's Avatar
 
Join Date: Oct 2002
Location: Round Rock TX
Posts: 2,913
Likes: 0
Received 2 Likes on 2 Posts

Default Another scaling idea..

I understang the correct way to scale a car is to pre-load the right rear by adjusting up and down on the adjustable QA1's. Well....this means with the car sitting still it will be preloaded. What about when the car transfers the weight and the front two tires are off the ground? Then the pre load is gone right?
Old 09-19-2006, 03:11 PM
  #2  
TECH Enthusiast
 
Maggie's Avatar
 
Join Date: Sep 2003
Location: Texas
Posts: 503
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by Tony Shepherd
I understang the correct way to scale a car is to pre-load the right rear by adjusting up and down on the adjustable QA1's. Well....this means with the car sitting still it will be preloaded. What about when the car transfers the weight and the front two tires are off the ground? Then the pre load is gone right?
IMHO adjusting shocks is not the correct way to scale a car...adjusting wheelrate is effective using the adjuster on the shock but you can loose spring span and limit the travel.

When the front tires are off the ground 100% of the cars weight is on the back tires. There is no wheelrate effect from the front wheels at that time.

Last edited by Maggie; 09-19-2006 at 03:17 PM.
Old 09-19-2006, 09:14 PM
  #3  
LS1Tech Sponsor
iTrader: (4)
 
MADMAN's Avatar
 
Join Date: Jan 2002
Location: At the track
Posts: 5,295
Likes: 0
Received 4 Likes on 4 Posts

Default

I set the car using spring preload. BUT I also raise the front and load the rears to check. The only problem is the torque of the motor doesnt come into play. This isthe reason for my settings being a little on the heavy side.
__________________
www.madmanandcoracing.com


225-343-9029
Old 09-20-2006, 12:44 AM
  #4  
TECH Enthusiast
 
Maggie's Avatar
 
Join Date: Sep 2003
Location: Texas
Posts: 503
Likes: 0
Received 1 Like on 1 Post
Default

Madman has alot of experience and has been doing this along time. He is very intuitive when it comes to race cars and is very good at visualizing diagonal load effects.

If you guys are going to scale you own car and use spring loading ("spring preload") to tune for wheelrate it is important not to exceed the manufacture's frequency rating of the spring.

Guys, the benifits of scaling a car are well worth the time and money on a dedicated race car. Do your reasearch and do it right.

Here is a brief primer:
With the car on the scales, and the scales on Blocks that will allow for 10-12 inches of tilt, Block the suspensions travel, air up the front tires to about 45-50 lbs (the tires are a working part of the suspention also). If you can find some hard tires the same size as your slicks put them on,(unless you are running a radial). Slicks will stretch if you air them up enough to eliminate tire sqash. With the driver in the car and fuel in the tank, weigh the car level, tilt and reweigh. Measure the angle of tilt. Calculate the Height of the center of gravity.
What you will need to record:
Front Weight of the Car
Rear Weight of the Car
Total Weight of the Car
Angle of the tilted car
Front Weight of the car tilted
Raised Height of Rear of the Car
Wheel Base
(it's late and I'm tired, I hope I didn't leave something out)

Once the height of center of gravity for the car is known, diagional preload AND torque effect can be calculated.

I won't get into the math expressions in this post. It should be easily found on th net.

Last edited by Maggie; 09-20-2006 at 12:53 AM.
Old 09-20-2006, 08:33 AM
  #5  
8 Second Club
Thread Starter
iTrader: (4)
 
Tony Shepherd's Avatar
 
Join Date: Oct 2002
Location: Round Rock TX
Posts: 2,913
Likes: 0
Received 2 Likes on 2 Posts

Default

Good info! Thanks to both of you!! I meant adjust by springs not shocks.

Last edited by Tony Shepherd; 09-20-2006 at 04:46 PM.
Old 09-20-2006, 03:57 PM
  #6  
Teching In
 
ottopsycle's Avatar
 
Join Date: Sep 2006
Location: North Texas
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Default



WOW!!!
GOOD stuff!!! This site is Great!...I LOVE this board. I lOVE you GUYs!!!
Old 09-20-2006, 03:59 PM
  #7  
TECH Enthusiast
 
Maggie's Avatar
 
Join Date: Sep 2003
Location: Texas
Posts: 503
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by ottopsycle


WOW!!!
GOOD stuff!!! This site is Great!...I LOVE this board. I lOVE you GUYs!!!

Michael... easy there big boy. Now put down the mouse and BACK away from the Keyboard.

You are getting way overstimulated....
Old 09-20-2006, 04:10 PM
  #8  
Teching In
 
ottopsycle's Avatar
 
Join Date: Sep 2006
Location: North Texas
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Maggie
Michael... easy there big boy. Now put down the mouse and BACK away from the Keyboard.

You are getting way overstimulated....

Hey Maggie,
Maybe I should take a cold shower or something.
I was a little over exuberant.
Old 09-22-2006, 03:28 PM
  #9  
TECH Fanatic
iTrader: (3)
 
Fire67's Avatar
 
Join Date: Feb 2005
Location: Naples, FL
Posts: 1,118
Likes: 0
Received 0 Likes on 0 Posts

Default

D@mn!
Tony, when its time to start trying to dial my supension in, your gonna get lots of calls from me on this stuff.
Old 09-22-2006, 05:07 PM
  #10  
TECH Senior Member
iTrader: (2)
 
gator's 99TA's Avatar
 
Join Date: Nov 2001
Location: Tampa Bay
Posts: 9,971
Likes: 0
Received 2 Likes on 2 Posts

Default

killer post!




All times are GMT -5. The time now is 10:11 AM.