Do rear sway bars affect dragstrip launch?

[Ghoste]

And that's pretty much it, does a rear sway bar affect launching a street/strip car in any way positive or negative?

[Mike DC]

Probably a mild positive effect.  Just from the fact that it would fight the torque-loading issue.  (Where the axle wants to plant the LR tire harder and lift the RR tire.)

 

[aifilaw]

They certainly do, but not as much as ladders or pinions, the typical mopar drag-setup is as simple as follows:
Add rear sway bar
remove front sway bar
add pinion snubbers
add front solid ladder bars
take to drag strip and adjust pinions as required.

[hemihead]

I disagree . You don't really want to run a car with only a rear bar . Does very weird things to the steering .

[Ghoste]

I generally loosen the swaybar off on my car at the dragstrip but I don't have a rear bar.  Hemi springs, pinion snubber and heavier shocks are as high tech as my car gets.  I was just curious about the rear bar thing and I don't even remember why.  I musta been looking at pictures of TA Challengers or something that day.

[firefighter3931]

Anything that limits rear end rise will have a negative impact, inmo.


Ron

[Ghoste]

So you DON"T like rear sway bars on a drag car?

[aifilaw]

they help to reduce rear travel, that's why they are part of the standard arsenal, but they are the last on the list of all things

[Ghoste]

So you DO like them?

Hmmm, perhaps a better question would have been how much do you think it affects a street/strip car (in et)?

[aifilaw]

Since ET is the only thing that counts, and the most important part of ET is launch....

I'll try to quantify things, although I will probably screw this up...but I'm not exactly sober right now anyways, so what the hell....

The perfect launch is created by many things proportionally.

50% (Tire Grip)
10% Torsional Movement reduction downward force (Rear Springs)
10% Torsional Recovery (rear shocks)
10% Torsional stability rear facing keeping the differential from pitching downwards on the pinon angle (Pinion snubber)
10% Torsional stability rear facing keeping the differential from bitching downwards on the pinion angle (Ladder Bars)
0% Ensuring equal torsional force loading on both sides of the differential (moving the center section to the left or right to account for torque) (nearly impossible to do, so they( the manufacturer) best-guesses it)
5% Equalizing torsional force loading on both sides of the differential (Sway Bar)
5% Reduced Wheel Hop after initial hooking (handled by either ladder bars(don't use torsion bars) or rear axle - front-side lower control arms)


In reality the percentages could be split up differently, and probably should... but like I said... too drunk right now to BS it and I lack the true data comparison that you will want for such a specific question, you will just have to rely on years of experience.