Pre loading on launch

Old 08-05-2009, 07:14 PM
  #1  
shortysracing
Junior Member
APPRENTICE
Thread Starter
 
Join Date: Jun 2009
Posts: 10
Default Pre loading on launch

Drive a 79 camaro. Would it be a good idea to preload the rear of the car?
shortysracing is offline  
Old 08-06-2009, 01:35 AM
  #2  
TS1955
Senior Member
DYNO OPERATOR
 
Join Date: Aug 2007
Location: Lost Creek, WV
Posts: 533
Default

If it launches straight, NO!

TS1955
TS1955 is offline  
Old 08-07-2009, 03:52 AM
  #3  
BillyShope
Member
CRAFTSMAN
 
Join Date: Jul 2007
Location: Orlando
Posts: 58
Default

Unfortunately (or, perhaps, fortunately), a car can launch straight and still be losing performance because the rear tires are not equally loaded. A Camaro with stock suspension will unload the right rear due to driveshaft torque. As any roundy-round racer would agree, maximum performance from a tire pair is achieved when they're equally loaded.

Having said all that, I, too, would say NO to static preloading. The problem with static preloading is that the necessary amount is so large that you end up affecting handling on the street. You might consider some of the other techniques at my site and save preloading for fine tuning.
http://www.racetec.cc/shope
BillyShope is offline  
Old 08-07-2009, 05:16 AM
  #4  
TheRabbit
Senior Member
RACING JUNKIE
 
TheRabbit's Avatar
 
Join Date: Jan 2007
Location: Augusta, Ga.
Posts: 2,276
Default

There's a lot more to it than just going straight. Eventhough they launch straight I've seen many cars and trucks pick the the left front tire 3 feet in the air and the right tire is still on the ground. In other words the chassis is so twisted the weight is not on both rear tires equally. An anti- roll bar or pre-load bar will take a ton of that twisting out and get your 60' times down a good bit. I agree, do not use a pre load bar to correct a bigger problem.
TheRabbit is offline  
Old 08-07-2009, 07:57 AM
  #5  
TheYellaBrick
Senior Member
RACING JUNKIE
 
TheYellaBrick's Avatar
 
Join Date: Mar 2008
Location: Emmett, Idaho
Posts: 7,334
Default

Any sort of motion other than forward is time being added to your E.T..
Chassis(suspension) flex and wheels up action is one way to 'soften' the launch and ease shock on the drivetrain components including the rear tires(traction).
TheYellaBrick is offline  
Old 08-07-2009, 10:39 AM
  #6  
FullTimeRacing
Senior Member
DYNO OPERATOR
 
Join Date: Mar 2008
Location: New Orleans,La
Posts: 515
Default

What do you guys mean buy preloading?

stalling it up ?

or jacking one side up higher,like the right rear?

just want to be clear.
FullTimeRacing is offline  
Old 08-07-2009, 12:34 PM
  #7  
TheRabbit
Senior Member
RACING JUNKIE
 
TheRabbit's Avatar
 
Join Date: Jan 2007
Location: Augusta, Ga.
Posts: 2,276
Default

I think he was asking about an Anti Roll bar (or pre load as some people call it) to control side-to-side body roll during hard
launching.
http://www.competitionengineering.co...?CatCode=13048
TheRabbit is offline  
Old 08-07-2009, 01:01 PM
  #8  
TS1955
Senior Member
DYNO OPERATOR
 
Join Date: Aug 2007
Location: Lost Creek, WV
Posts: 533
Default

There is a lot of good info. here. BUT, ( and I'm not a chassis guy and trying to learn) I thought an anti-roll bar was just that. A torsional bar to prevent chassis roll and pre-load was done by rotating, usually the upper right, 4-link bar to change the amount of weight on the corner of the car?

TS1955
TS1955 is offline  

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


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -