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Author Topic:   Lifting with a swingarm
WPP
Dirt Full Roller

Total posts: 46
posted July 03, 2001 07:18 PM

There are some mods beating me pretty bad and we all are running swingarms but the ones in front of me left rears are lifting in middle of the turn mine does nothing No squat or lifting just stays the same 300 lr 250 rr with a 900 torque link with 2 1/4 movement it just sims they have a little bit more bite how could i make my car do this i would like to try it

irace74
Dirt Roller

Total posts: 24
posted July 03, 2001 09:58 PM
I think in general that raising your ride height inthe rear will assist you. The angle of the swing arms should be adhjusted similar to that of a 3 link car in that the left rear should be higher then the right rear at the chassis connection. Further investigation into panhard bar location, frnt springs and 3rd link location all have an effect on the set-up you are working with. Get teh car into the corner, have it transfer weight onto the right rear, pick up the throttle and watch the left rear plant. The syuspension on the car must work, don't let it sit there flat.

WPP
Dirt Full Roller

Total posts: 46
posted July 04, 2001 08:12 AM
Can you explain how the ride height works my ride heights are 6 1/2 rr 6in on the lr with 19 1/2 swingarms i evevn thought about go ing to smaller swingarms thanks for the help

WPP
Dirt Full Roller

Total posts: 46
posted July 04, 2001 08:16 AM
My front springs are lf 750 and rf 800 with 15 degrees in the left and 12 degrees in the right on the swingarms

irace74
Dirt Roller

Total posts: 24
posted July 04, 2001 03:13 PM
Seems to me that the awing arms are nearly paralle. Raise the chassis connection on the left rear. Further, raise your panhard bar equally on the rear end and the chassis a little, this will raise the rear roll center promoting weight transfer, On corner entry the left rear should unload and weight should be transfered to the right rear. When you get back into the throttle, the weight should transfer from the right front back to the left rear planting the left rear for forward bite. If there is excessive panhard bar angle the weight transfer will bind from excessive bar geometry.
By raising the rear ride heights, this too raises the rear roll center and promotes left to right weight transfer. Because you are just raising the chassis side of the panhard bar, the increased angle will tighten the car slightly but, with the higher schassis the car should get over to the right rear more quickly. THe panhard bar should keep you tight enough in th middle of the corner.

WPP
Dirt Full Roller

Total posts: 46
posted July 05, 2001 05:14 AM
Right now i am running a 22inch j-bar from the ground to the pinion mount it 8 inches in the bottom hole and on the chassis it is 12 inches from the ground . What do you think about going to a shorter swingarm my car is 108 wheelbase. THANKS FOR THE HELP

irace74
Dirt Roller

Total posts: 24
posted July 05, 2001 09:44 AM
Afco would recommend that you utilize a maximum of a 2" drop in in the panhard bar. Their latest material has slightly come off of this but let's assume that it is an ok place to start. I would raise the bar on the pinion 1 hole, therefor raising the rear roll center. To counteract this change, you might add wedge, increase the right front spring by 50# or soften the right rear spring by 25#. All of this should allow the car to roll over faster entering the corner,yet tightening it comming off. THe shorter length swing arms are an OK idea but, remember the effective length of the arm has an effect on spring rate. The springs on a shorter arm will generally tend to be stiffer then on a longer arm due to the leverege effect of the length of the arm. By simply bolting on the shorter arms, you will be significantly softening the rear of the car, therefore, tightening the overall set-up.

Sidebite
Dirt Forum Racer

Total posts: 96
posted July 09, 2001 04:17 PM
Any success in getting that swingarm to lift?

DYOUNG
Dirt Newbie

Total posts: 1
posted July 19, 2001 05:02 PM
quote:
Originally posted by irace74:I
Seems to me that the awing arms are nearly paralle. Raise the chassis connection on the left rear. Further, raise your panhard bar equally on the rear end and the chassis a little, this will raise the rear roll center promoting weight transfer, On corner entry the left rear should unload and weight should be transfered to the right rear. When you get back into the throttle, the weight should transfer from the right front back to the left rear planting the left rear for forward bite. If there is excessive panhard bar angle the weight transfer will bind from excessive bar geometry.
By raising the rear ride heights, this too raises the rear roll center and promotes left to right weight transfer. Because you are just raising the chassis side of the panhard bar, the increased angle will tighten the car slightly but, with the higher schassis the car should get over to the right rear more quickly. THe panhard bar should keep you tight enough in th middle of the corner.


ALL I HAVE READ IS THAT WHEN YOU RAISE YOUR PANARD YOU RAISE THE ROLL CENTER,BUT THIS INCREASES SPRING RATE WITCH STIFFENS THE CAR ,AND PREVENTS THE CAR FROM ROLLING,LOWERING THE BAR WILL LOWER ROLL CENTER AND AND SOFTEN THE SPRING RATE,AND THIS LETS THE CAR ROLL,IF A CAR IS LIFTING IN THE CORNER,THEY HAVE CLAMPED THE LEFT REAR OF THE Z-LINK AND DRIVES THE LR IN THE GROUND PROMOTING FORWARD BITE. I'M NEW IN HERE BUT I WAS READING WHAT YOU WERE TELLING THE OTHER GUY AND IT DOESN'T HAPPEN THAT WAY I HAVE BEEN DOING THIS FOR 18YRS,I CALL AFCO AND GOT THEM TO SEND ME AN AFCO TECH MANUAL AND IT HAS SOME GOOD INFO IN IT ON ALL YOU NEED TO KNOW

BENDER27
Dirt Roller

Total posts: 6
posted August 13, 2001 01:02 AM
Are you sure that raising or lowering panhard bar changes spring rate?

Dan 21
Dirt Roller

Total posts: 18
posted August 13, 2001 07:48 AM
WPP Where is your lift bar located center of rear wheel track or to the left side ?If you want more lift at the left rear move the bar 2-3 inches to the left of center. Also you can lower the front of the lift bar and this will help.For more lift and bite you can go too a stiffer spring and it will help a lot.With 2 1/4 " of travel on your spring bar you are losing a lot of lift.We started with a 1500 and now use a 2500 spring .This gives a lot of bite to our 3 link and it only has 3/4 "travel. Dr21

Dan 21
Dirt Roller

Total posts: 18
posted August 13, 2001 08:01 AM

WPP You did not give much info.on setup such as total weight ,wheel weights,front springs and bite in car. If you do not want to post this just try the info.in the above post and see how it works for you. Good luck DR21

WPP
Dirt Full Roller

Total posts: 46
posted August 13, 2001 08:14 PM
DAN21 300 lr 250 rr 800 rf 750lf springs 58% REAR 52 % CROSS 125 left rear the torque link is in the center of the rear goes to the right at the chassis some I have made a new place on the left of the drive shaft loop to try but clearance might be a problem . I have an afco torque link 900 pds 17 degrees .

Dan 21
Dirt Roller

Total posts: 18
posted August 14, 2001 08:57 AM

WPP if i understand right all you really wanted to know is how to make your car lift up on the L.R.under power right? With the pull bar in center of rear and pointed to right on chassis it pulls up on right side of chassis more.If you can move the bar to the left about 2-3 inches .keep it as straight as possible. If you have clearance problems look at your rear mount and see if you can drill another hole to move up or down for front to rear clearance.We have one at 11 "and one at 13 ". At front 10 to 25 degrees.When i center pull bar i do this at center of track width then move it left as much as needed.Going to a stiffer spring will make a big differance in lift and bite.Does your bar have one spring or two? Some of the afco bars have two springs and you can remove the little one and replace it with a spacer and it will work better.When i changed to the 2500 #spring it was a world of differance,good lift and bite.If you try this let me know how you like it. Happy Racing and good luck DR21

WPP
Dirt Full Roller

Total posts: 46
posted August 14, 2001 05:06 PM
Dan my torquelink has only one spring and the back of mine is in the center of the car were it mounts to the front of the chassis is were it goes to the right . If i am thinking right you do move the whole link to the left. I was told i could move the back of the torque link to the left and it would help bite on the left rear but i knew if i done this it would angle it to the right even more were it hooks up on the chassis.

CUZZ45
Dirt Roller

Total posts: 7
posted August 14, 2001 06:56 PM
ONE OF YOU IS TALKING ABOUT A PULL BAR AND THE OTHER A LIFT BAR I DO BELIEVE

Dan 21
Dirt Roller

Total posts: 18
posted August 14, 2001 09:51 PM

WPP Just for the heck of it please describe in detail just what this link looks like ok.You are correct about mounting the link straight with center line of chassis.When you have it centered at rear mount and angled to the right on chassis it will not do what you need it to do for you.Get it mounted where it will be at least 2-3" left of center of rear track width and use a stronger spring .Keep it at the 17 degree downward angle until you have tried it then you might want to go down 5 degrees more.This should give you lift and more bite.Each time we have increased the spring rate we have gotten more lift and better foward drive.Works real good on dry slick.Set pinion angle 6-7 degrees and try to keep preload off spring bar.Is your link one of those that has a decell. stop on it too keep from going too far down when you get off the gas ? DR21

WPP
Dirt Full Roller

Total posts: 46
posted August 15, 2001 08:54 PM
Dan my torque link is from afco and it is like a pull bar that hooks to the rearend and hooks to the chassis with one spring.

Dan 21
Dirt Roller

Total posts: 18
posted August 15, 2001 09:20 PM
WPP Knew that from the start.Do not think some others understood because we called it a lift bar at times.Have three of them and have called them a lot worst.Just try what i told you and let me know how it works for you.If it makes car to tight off corner add some rear stagger or take some L.R. bite out.There are other things you can do if it is too tight but just try this for now .You can make j-bar or panhard bar adjustments to help lift left side also but do this first. Good Luck DR21

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