Can anyone explain anit-squat?

[23firefly]

I'm trying to understand anit-squat in regaurds to a four link rear, but have yet to find an explination that I can wrap my small brain around.
Any BIG brainer out there who can help explain this?

 

[chuck]

As I understand it, when you accelerate hard from a stop the rear raises instead of squats.

 

[68ford]

anti squat i believe is when your ass end lifts when you take off. it all has to do with a properly designed 3 or 4link, everything is critical, lower link lengths,the upper link lengths, the angle of the 2 mounting points on the axle(looking from the side), the angle between the upper and lower links in comparison to one another, the distance appart from the the upper mounts and lower mounts on the frame.the width of mounts on axle compared to the width of the frame is also important. everything works together, done right the drive shaft should get shorter as the axle doops down. and the theroretical point at which the upper and lower links should meet should be where the middle of the weight is of the truck.
four links are rarely done right and sometimes with the height and length of wheelbase it can be impossible to do it correctly. there is and engineering program that can be used for calculating 4link suspensions, but i dont know the name.

 

[68ford]

well thought out 4link ;D

money obviously helps.

 

[23firefly]

Okay that makes sence. So I guess the next question would be how do I design the right four link rear?
I have pluged some numbers into the 4barlinkV3.0 program but not real sure what numbers to be shooting for. Most of our broncos are the same dimentions so are there any standard numbers for seting up a good 4 link?

Is this the program "4barlinkV3.0" the one your talking about for designing the four link?

 

[daddyo]

When you accelerate, your rig wants to squat (a week attempt at a wheelie).
Anti-squat is an effect built into some rear suspensions that makes the rear
suspension want to extend as your wheels accelerate you forward. When you
put on the brakes, the opposite happens.

Andrew

 

[23firefly]

I see what your saying Andrew, that makes sense.

As for the the pic's of the four link system........Well........looks like an over kill for my 69 bronco but I have to admit it's very Cool!

 

[sstlaure]

It's a fairly complex thing to explain. Go to your local library and try to find some of these references. The principles in there are what we used for this truck. Couldn't be happier with how it performs.

1. Adams, H, Chassis Engineering: Chassis Design Building & Tuning for
High Performance Handling, First Edition, HPBooks, New York.

2. Gillespie, T., Fundamentals of Vehicle Dynamics, First Edition, SAE, 1992.

3. Milliken & Milliken, Race Car Vehicle Dynamics, Fifth Edition, Milliken Research Associates, 1995.

4. Milliken & Milliken, Chassis Design: Principles and Analysis, First Edition, Milliken Research Associates, 2002.

 

[eds66bronco]

here is some more info to make your brain hurt %)

http://www.pirate4x4.com/forum/showthread.php?t=7503&page=1&pp=25

http://www.pirate4x4.com/forum/showthread.php?t=168577&page=1&pp=25