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wepsbee
06-28-2011, 07:41 AM
I have disconnected the front sway bar in my FWD Ford Escort Gt.
I have 500lb springs in front, 600 in rear. Koni double adjustable struts, 8611's
This action has been recommended to me for better cornering.
However without being able to run a test day prior to a race I am
a little apprehensive as to what it will handle like.
What kind of handling changes can I expect or what should I look for.
Does this make sense to try without a test day?
Thanks

gran racing
06-28-2011, 07:56 AM
I guess qualifying will be your test day.

Related to this discussion, for FWD cars, what are the benefits / disadvantages of disconnecting the front bar?

If this is done, do you typically change spring rates?

EH9racing
06-28-2011, 08:18 AM
You should expect slower turn-in and less understeer mid corner. The car will be less flat through the corners as well, which may unload the inside rear tire more, assuming your rear sway bar is beefy.

Also rumble strips shouldn't upset the front as much because those bumps won't be transfered over to the tire doing most of the work. However since the rear end could be more loose, be cautious the first few times over the rumbles.

wepsbee
06-28-2011, 09:37 AM
You should expect slower turn-in and less understeer mid corner. The car will be less flat through the corners as well, which may unload the inside rear tire more, assuming your rear sway bar is beefy.

Also rumble strips shouldn't upset the front as much because those bumps won't be transfered over to the tire doing most of the work. However since the rear end could be more loose, be cautious the first few times over the rumbles.

Less understeer would be great, I assume an earlier turn in would help and the rear end loose could help somewhat as now I have to feather the gas in a turn to try and get some rotation.

wepsbee
06-28-2011, 09:38 AM
I guess qualifying will be your test day.

Related to this discussion, for FWD cars, what are the benefits / disadvantages of disconnecting the front bar?

If this is done, do you typically change spring rates?
I do expect to increase the front springs to 600 to start. perhaps go up from there.

Yeah qualifying will be an adventure for awhile!!

SMac92
06-28-2011, 10:12 AM
Wouldn't increasing your Front spring rate be going in the opposite direction? I kind of look at sway bars like a beam suspension,which uses horizontal steel plates instead of springs. The steel twists when you turn and he more steel bars you have, the stiffer it is. With sway bars it is kind of the same way. In FWD we want the rear end to come around, so we have a big (stiff) rear bar and little to no front bar (soft). I think adding a stiffer front spring would set you backwards a bit and the car will understeer more, much like if you still had the front sway bar on. Changing springs is not necessary, I think it's important to get your spring rates where you like them and where the car handles well. Then use the shocks to fine tune the springs, and after that, adjust the sway bars to perfect your setup. All three are working together, but I think it's good to look at the big picture (springs) then go to the more finite things (sway bar) to perfect it.

On another related note, I have an adjustable sway bar. Right now it is mounted at the front hole. Will moving the mounting point backwards increase stiffness?

I hope this helps, and I would enjoy reading others opinions on setup, it's probably my favorite component of the car.

Steven

DoubleXL240Z
06-28-2011, 10:25 AM
^^^^^^ What he said!!!!!:happy204::happy204:

wepsbee
06-28-2011, 10:29 AM
Wouldn't increasing your Front spring rate be going in the opposite direction? I kind of look at sway bars like a beam suspension,which uses horizontal steel plates instead of springs. The steel twists when you turn and he more steel bars you have, the stiffer it is. With sway bars it is kind of the same way. In FWD we want the rear end to come around, so we have a big (stiff) rear bar and little to no front bar (soft). I think adding a stiffer front spring would set you backwards a bit and the car will understeer more, much like if you still had the front sway bar on. Changing springs is not necessary, I think it's important to get your spring rates where you like them and where the car handles well. Then use the shocks to fine tune the springs, and after that, adjust the sway bars to perfect your setup. All three are working together, but I think it's good to look at the big picture (springs) then go to the more finite things (sway bar) to perfect it.

On another related note, I have an adjustable sway bar. Right now it is mounted at the front hole. Will moving the mounting point backwards increase stiffness?

I hope this helps, and I would enjoy reading others opinions on setup, it's probably my favorite component of the car.

Steven
Makes alot of sense. The wheels will act independently though without the sway bar rather than together. The stiffer springs would get rid of the diving action going into a turn. I thought that action should be lessened somewhat.
Great thought.... I will try current spring and see how much I dive, maybe I need it just as is.
Thanks

jimbbski
06-28-2011, 02:07 PM
Te bottom line is make only one change at a time. Disconnecting the front bar and adding stiffer front springs is "2" changes! If you don't like the change you won't know which one is the problem and if the car goes faster which one helped!

shwah
06-28-2011, 02:27 PM
The most common reasons that people run with no front anti-roll bar in fwd applications are to promote rotation, and to improve corner exit traction. The balance/rotation aspect has been covered. Because the anti-roll bar ties the front wheels together, they reduce the vertical load on the inside front tire during body roll. If there is an open, or low torque locking differential, this can cause wheel spin.

rhygin
06-28-2011, 05:12 PM
On another related note, I have an adjustable sway bar. Right now it is mounted at the front hole. Will moving the mounting point backwards increase stiffness?



Moving to hole further away from the sway bar fulrum (chassis mount) "softens" the bar. moving closer provides less leverage and effectively makes the bar "stiffer"

wepsbee
06-28-2011, 06:35 PM
Te bottom line is make only one change at a time. Disconnecting the front bar and adding stiffer front springs is "2" changes! If you don't like the change you won't know which one is the problem and if the car goes faster which one helped!

Will do, one change at a time.

cjb25hs
06-28-2011, 08:12 PM
From my experience in making an ITA Neon ACR handle as good as it can get on a budget, I would make the following changes to your car.

700lb rear springs
Smaller front sway than the GT bar you can swap
And unless you already have one on the car, look at the biggest diameter adjustable rear bar you can get so you have some adjustability at the back.

At the very least you need more rear spring, also make sure your Konis are valved for the spring rate

Tim Dugan
06-28-2011, 10:02 PM
this is how i understand FWD cars. 10% pluse corner weight pluse a big bar in the rear makes the car go round and fast!! But watch out it is a lil tail happy. If u really wanna test the car make big changes than try try again till you get it the way u like it.:026:

Flyinglizard
06-28-2011, 11:54 PM
Pretty close on rates. That car should scale about 700# on the LF, maybe 650n the Rf.
The 500# may be a little low. The 650 in the rear should be close. But I dont know waht the wheel rate is RE the spring rate. The A arm cars are not 100% wheel rate to spring rate. You may need more or a little less. The car will be faster if you can get it to work without the front bar. If it felt good before , with the bar and 500s, you may want to go up some front spring, 600# should be very close, figuring around 95%-99% wheel rate . Toe out the rear a bit , 3mm , buy my book, go faster. MM

wepsbee
06-29-2011, 08:26 AM
Pretty close on rates. That car should scale about 700# on the LF, maybe 650n the Rf.
The 500# may be a little low. The 650 in the rear should be close. But I dont know waht the wheel rate is RE the spring rate. The A arm cars are not 100% wheel rate to spring rate. You may need more or a little less. The car will be faster if you can get it to work without the front bar. If it felt good before , with the bar and 500s, you may want to go up some front spring, 600# should be very close, figuring around 95%-99% wheel rate . Toe out the rear a bit , 3mm , buy my book, go faster. MM

Thanks, great info and will do on the book, did not know it existed.

wepsbee
06-29-2011, 08:28 AM
Thank you all for the info. Exactly what I was looking for, consistent, knowledgeable and informative, sometimes this forum really works!!!!!

wepsbee
06-29-2011, 08:33 AM
Pretty close on rates. That car should scale about 700# on the LF, maybe 650n the Rf.
The 500# may be a little low. The 650 in the rear should be close. But I dont know waht the wheel rate is RE the spring rate. The A arm cars are not 100% wheel rate to spring rate. You may need more or a little less. The car will be faster if you can get it to work without the front bar. If it felt good before , with the bar and 500s, you may want to go up some front spring, 600# should be very close, figuring around 95%-99% wheel rate . Toe out the rear a bit , 3mm , buy my book, go faster. MM

Bought it!!!!

Eagle7
06-29-2011, 12:19 PM
Thank you all for the info. Exactly what I was looking for, consistent, knowledgeable and informative, sometimes this forum really works!!!!!
It only really works if you end up going faster. :)

wepsbee
06-29-2011, 01:23 PM
It only really works if you end up going faster. :)

TRUE:happy204: