Rear Sway Bar Removal?...
06-24-2008, 01:09 AM
#1
TECH Addict
Thread Starter
iTrader: (41)
Join Date: Jun 2005
Location: Jefferson City, MO
Posts: 2,329
Likes: 0
Received 0 Likes
on
0 Posts
Rear Sway Bar Removal?... I was reading the latest GMHTP and they suggested losing the rear sway bar to allow squat and planting of the rear... I was always under the impression that you lose the front but keep the rear....
Thoughts?...Oh, and of course we are NOT suggesting this for a street driven car...
Thoughts?...Oh, and of course we are NOT suggesting this for a street driven car... 
06-24-2008, 07:10 AM
#2
TECH Regular
iTrader: (3)
Join Date: Jan 2005
Location: Magnolia, Texas
Posts: 464
Likes: 0
Received 0 Likes
on
0 Posts
For drags you want rear anti-squat, meaning you want the suspension to push the tires down when loaded with power for more grip. Squat means it's pulling them up and losing traction. Shorter torque arms and or lower control arm relocation brackets move the instant center of the rear suspension further back in the chassis so that power can actually push the chassis up and the axle down. This geometry works in the opposite direction under braking (or in reverse gear for you knuckle-heads who think WOT is the only speed) reducing rear brake effectiveness at higher speeds. Moving wieght towards the rear axle with these mods will help tremedously with rear anti-squat but may hurt without it if it bottoms out.
With a stock type suspension the rear anti-sway bar is also the lone defence against driveshaft torque (which due to gearing is higher than engine torque in the lower gears) twisting the static axle housing, thereby lifting the right rear tire off the ground with stock suspension when a heavy load is quickly applied. Removing the rear bar will allow the rear to twist unfettered (until control arm bind which is sudden and not good) when power is applied quickly, this is why larger rear bars are often used for better 60' times at the drag strip. Without it you had better preload the right rear with a stiffer spring or air-bag or similar to counteract the uneven load at launch or with sudden applications of high power. The uneven springs will make regular handling uneven. A balanced combination of many things will make the best street/strip suspension. Going all the way in one direction will cause the other to suffer.
In any case topping out against the shock limits or bottoming out the suspension on the bump stops when launching jolts the tires when they are at their limits of adheision doing all they can to maintain grip and will cause them to loose grip going from rolling to spinning when the suspension hits it's physicall limits. You can have too much of anything for your traction and power level. Type of transmission and launch techniques also are heavy factors.
I don't what GMHTP is shooting for but in almost every instance on a post '81 F-body with a stock style supension that advice is not good and makes no sence. I wonder if they meant to print "front bar". There are several good chassis and suspension companys here that you should consult first before following generic magazine advice. They will discuss your car, your driving needs and desires, and make a better recommendation that applies to you. There are several books you can read and study that will allow one to understand all of these factors and be able to make thier own decisions also.
Vernon
With a stock type suspension the rear anti-sway bar is also the lone defence against driveshaft torque (which due to gearing is higher than engine torque in the lower gears) twisting the static axle housing, thereby lifting the right rear tire off the ground with stock suspension when a heavy load is quickly applied. Removing the rear bar will allow the rear to twist unfettered (until control arm bind which is sudden and not good) when power is applied quickly, this is why larger rear bars are often used for better 60' times at the drag strip. Without it you had better preload the right rear with a stiffer spring or air-bag or similar to counteract the uneven load at launch or with sudden applications of high power. The uneven springs will make regular handling uneven. A balanced combination of many things will make the best street/strip suspension. Going all the way in one direction will cause the other to suffer.
In any case topping out against the shock limits or bottoming out the suspension on the bump stops when launching jolts the tires when they are at their limits of adheision doing all they can to maintain grip and will cause them to loose grip going from rolling to spinning when the suspension hits it's physicall limits. You can have too much of anything for your traction and power level. Type of transmission and launch techniques also are heavy factors.
I don't what GMHTP is shooting for but in almost every instance on a post '81 F-body with a stock style supension that advice is not good and makes no sence. I wonder if they meant to print "front bar". There are several good chassis and suspension companys here that you should consult first before following generic magazine advice. They will discuss your car, your driving needs and desires, and make a better recommendation that applies to you. There are several books you can read and study that will allow one to understand all of these factors and be able to make thier own decisions also.
Vernon
Last edited by Manic Mechanic; 06-24-2008 at 11:48 AM.
06-24-2008, 11:32 AM
#3
TECH Addict
Thread Starter
iTrader: (41)
Join Date: Jun 2005
Location: Jefferson City, MO
Posts: 2,329
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the response. Yea, trust me, rarely do I read a mag and go out and try something they advise. Half the time I think I know more than the person writing the article. This one just really jumped out at me as a "hey wait a minute". It just didnt make sense to me for all the reasons listed. Figured I would get some real world answers from guys who have maybe tried it.