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Author Topic:   locked lr birbcage
andykmod
Dirt Full Roller

Total posts: 40
posted November 28, 2001 11:55 PM
I run a z-link rear suspension i was wondering if u can lock the bird cage on the left rear for dry slick ? if you can what is the easiest way to do it ? also what other things might need to be changed to run it that way ? also both of my rear springs are in front of rear-end, would it be better to move the lr slider to a clamp bracket on the housing behind rear-end or maybe on the bird cage ????????

wfoondirt
Dirt Freak

Total posts: 242
posted November 30, 2001 02:14 PM
The way i have most often seen is to remove the top bar and weld tabs to the rearend to put a bolt though the top hole of the birdcage. Depending upon your setup you may have to reduce the angle in the lower bar after the b/c is locked, beacuse what you have done is converted it to a standard 3-link. As far as moving the spings, with the b/c locked mounting the spring to the back of the rearend or the back of the b/c is no different. The only possible advantage to mounting the spring to the b/c is that it will typically get the spring closer to the wheel.
You may also have to soften the rate of your torque-link/lift-bar because some of the torque will be absorbed by the trailing arm and lr spring.

andykmod
Dirt Full Roller

Total posts: 40
posted December 01, 2001 12:03 AM
what if i put the slider on a clamp bracket in front of the rear end with out locking the b/c? will that give me more forward bite? how about trying 4-bar lr z-link rr?

Tom Asmus
Dirt Maniac

Total posts: 161
posted December 01, 2001 08:45 PM
Why lock the bird cage I would think that this would bind the car up and not let weight transfer like it should. Are you havin handling or traction problems?

devil wrench
Dirt Full Roller

Total posts: 51
posted December 01, 2001 10:57 PM
A clamped-up setup relies on the traction of the track to create more traction by wrapping the axle up, thus adding wedge to the car through the coil. If there is no traction to cause the axle to wrap(dry slick), the clamp setup does nothing except get real loose into the corner. The best setup for dryslick conditions is the spring behind deal.

Tom Asmus
Dirt Maniac

Total posts: 161
posted December 03, 2001 06:55 PM
devil has a valid point. the rear end needs to wrap if it doesnt your just gonna burn the tires off. I run a swing arm car and all I do is change wheel offsets and right side shocks when the track goes dry slick. Also I change angle of my torque link and change the preload on the link also.

andykmod
Dirt Full Roller

Total posts: 40
posted December 03, 2001 11:23 PM
I usually get about 1 3\4 to 2 1\2 inches of travel on my pull bar i run a 1050lb spring my link mounts on the chassis are not adjustable (YET) would it help me if i could move both of my swing arms up a few inches? Right now they are at about 5 to 7 deg up hill toward the front of the car also i run a short panhard bar on the pinion with quite abit of angle,we get alot of latteral movement (good or bad?????)the car is a 97 kosiski. i started out with j-bar a fellow racer told me to try the short bar for the dry-slick seems to have more forward bite. my spring rates are lf.1050 rf.1150 lr.250 rr.200 we have tried dry-slick shocks but just not getting the results we need please help i wanna kick some a** next summer thanks guys

devil wrench
Dirt Full Roller

Total posts: 51
posted December 04, 2001 09:30 AM
I think you might want to soften the entire car up. It all seems really stiff to me. Anybody else?
Also, in the first post, you said it was a Z link. Then in the last post, you talked about raising the swingarms. Which is it? Are the springs mounted on a birdcage or the trailing arms?

[This message has been edited by devil wrench (edited December 04, 2001).]

Tom Asmus
Dirt Maniac

Total posts: 161
posted December 04, 2001 10:31 PM
Yeah I agree the spring rates are way too stiff soften them up. Try runnin an 850 RF, 750LF, 275LR, and 225RR. I also run a buscuit pullbar from allstar performance and it is great on dry slick for me! As for your panhard bar length, are you using a straight short bar? Is the car real loose into the corners etc.. with a short bar if it is straight you arent gonna get much body roll or weight transfer. Where I race a guy tried that and the car just acted EVIL!

andykmod
Dirt Full Roller

Total posts: 40
posted December 04, 2001 11:46 PM
the car is a z-link with the sliders on the swing arms i tried the 850 rf and the 750 lf and the car had less forward bite as for the panhard bar it is about 9 inches long and has alot of angle in it,the car rolls on to the rr alot the car has awsome side bite but not as much forward bite as i need ?????? i'am running 250 lr 200rr springs should i try more split like 300lr 200rr and then take some angle out of the panhard bar ?WHAT SHOULD I BE RUNNING FOR DIA. ??? WILL THE DIA.HELP THE CAR DOWN THE STRAIGHTS AND HURT IN THE TURNS? THE CAR TURNS GREAT RIGHT NOW I DON'T WANNA MESS THAT UP ITS THE ONLY PLACE I CAN PASS CARS RIGHT NOW THANKS

devil wrench
Dirt Full Roller

Total posts: 51
posted December 05, 2001 09:28 AM
OK. When the sliders are mounted on the swingarms, it is a SWINGARM suspension, not a Z-Link. A Z-Link suspension, though looking quite similar, acts much differently; this is because the sliders are on the birdcage.

Now that we have that cleared up, a LF that is stiffer than the RF will help the car turn. I think this is where your problems are starting. Try an 850 LF, 750 RF, 275 or 300 LR, and a 175 or 200 RR.

You didn't give any numbers for LS%, RR%, or wedge, but if your car has that much side bite and won't go forward, I would add wedge to the car in 25 lb increments until you start to loosen the car coming in. Then you'll be able to find the happy spot for the setup.

Also, when we run the short-straight panhard bar, we usually only have about 1"-2" of angle in it; because as the car hikes up, the bar becomes **** near vertical. I'm guessing that yours is getting vertical completely, due to all the angle in it to begin with. Make sure that it isn't hitting the bottom of the mount on the frame as that would cause the tires to break loose coming out of the corner.

[This message has been edited by devil wrench (edited December 05, 2001).]

andykmod
Dirt Full Roller

Total posts: 40
posted December 06, 2001 12:34 AM
I have tried dia anywhere from 47% to 51% It seemed like the more dia i ran the tighter the car became in the middle of the turn. 0n the dry slick the car would push pretty bad in the middle and on the tacky i would have to drive it very hard and did not feel comfortable. The car has 51.5% ls and 59%rear i usually ran 48% dia and the car worked the turns real well. By having a softer rf spring won't that hurt the forward bite because the rf spring is not holding weight on the lr? I do see what you getting at though raise the dia which should tighten the car and then run a softer rf spring to help the car turn,right? Also by adding wedge (dia) won't that tighten turn entry??? Dose the lr slider on a clamp bracket in front of the rear end still hurt forward bite now that we know it is a SWINGARM???? THANKS FOR ALL THE ADVICE GUYS --------- ANDY

WPP
Dirt Maniac

Total posts: 162
posted December 06, 2001 05:28 AM
I run a heavier spring on my rf 900 and a 700 on the lf If the rf spring is to soft the car will dewdge and be loose 325 on the left swingarm and 275 on the righthat what i found works the best for me.

kain
Dirt Roller

Total posts: 7
posted December 07, 2001 05:10 PM
I run a swing arm car with 850lf 800rf 225lr 200rr 52%ls 54%dia 58%rear and a short bar with about 5in. of split. The car is a little loose entering but real good from the center out. Any ideas to tighten up entering? By the way the lr is on a clamp bracket.

andykmod
Dirt Full Roller

Total posts: 40
posted December 07, 2001 11:56 PM
Maybe dial in some more front brake that should tighten up entry a-bit,also do you run a pull bar or lift bar? You could switch your front springs around or maybe try a shock with stiffer compression on th rf.How much stager do you run,you could Destager it alittle.What i would try is raise the front of the axle dampner that should tighten you up a LITTLE comming in hope this helps. How do you like it with the lr on the clamp bracket and what spring do you run in the pull bar or lift bar? thanks for you help

kain
Dirt Roller

Total posts: 7
posted December 08, 2001 08:27 PM
I run a short pull bar with a 900# spring, and usually run 0 to 1" of stagger. I also have two 90/10's on the rear. As far as running the clamp, I won't run without, great bite from the center out. I also think running a stiffer lf spring helps tighten up entering the corner. What do you think?

andykmod
Dirt Full Roller

Total posts: 40
posted December 09, 2001 03:25 AM
I BELIVE THAT INCREASING THE LF SPRING RATE WILL LOOSEN YOU UP COMMING IN BECAUSE IT WILL HELP TRANSFOR WEIGHT ON TO THE RIGHT FRONT WHICH WILL GIVE THE RF MORE BITE, BUT IT WILL ALSO LOOSEN YOU COMMING OUT BECAUSE IT IS PUTTING WEIGHT ONTO THE RR INSTEAD OF THE LR JUST MY THOUGHTS.MAYBE THE TWO 90/10'S ARE LOOSEN YOUR ENTRY, WHY DO YOU RUN 2 OF THEM? TO SLOW DOWN REAR END MOVEMENT?ALSO WHAT TYPE OF CHASSIS DO YOU RUN? WHAT LOWER CONTROL ARMS DO YOU RUN? I RUN OLD NOVA'S AND NOT SURE IF I WOULD NEED STIFFER FRONT SPRINGS BECAUSE OF THE ANGLE THE SPRINGS ARE ON IN THE POCKETS.(LEVERAGE)

kain
Dirt Roller

Total posts: 7
posted December 09, 2001 10:26 PM
The car has a Impala front clip with stock A arms. The pull bar is far to the left and adding the second shock to the far right seemed to help the car on entry.

andykmod
Dirt Full Roller

Total posts: 40
posted December 11, 2001 02:54 AM
what do you think would happen if i locked the lr bird-cage,which would turn it into a three link on the left rear right? Would it give it more roll steer? Is that good or bad? I wanna keep the lr on a clamp bracket right? Wanna hear your opinion

kain
Dirt Roller

Total posts: 7
posted December 11, 2001 10:10 PM
I don't think i would lock the birdcage,if you are looking for more steer put more angle up in front and more angle down on the rear bar. The amount of steer you need will depend on your track and the way your car reacts. I would try the clamp bracket first and see how you like it.

andykmod
Dirt Full Roller

Total posts: 40
posted December 12, 2001 12:51 AM
I'am going to try the clamp bracket forsure i think that will help my forward bite.If i was to try the locked cage what would happen,would make the car (evil) tight to loose real quick? What do you think the car would do? I know when i try the clamp bracket i will have to drop my pull bar rate alittle right? I'am running a 1050lb right now and will try the 900lb to start. My car has no adjustment for the swingarms or the rear links yet but i plan on adding them when i get the car on the jig next week.I just heard that locking the bird cage on the lr makes that side a 3-link and you get awsome bite,bite that carrys the lf about 6 to 8 inches of the track when the car is hooked is that true?

andykmod
Dirt Full Roller

Total posts: 40
posted December 16, 2001 09:19 PM
I would like to hear your thoughts on this subject.I wanna know what to try and what not to try. THANKS GUYS

Tim Terrell
Dirt Newbie

Total posts: 3
posted December 19, 2001 06:21 PM
would like to give some information on setup.
run a modified we build ourselves(metric). i run a 800rf/750lf---250rr/325lr w/ about 58%rear-51% left. about 80# of leftrear. run a springbar w/ a progressive spring. long panhard bar behind rearend. car is a z-link swing arm car w/ shocks on the swing-arms(went from shocks on b/c behind rearend to shocks on swing-arms) could tell a big difference, gave me a little more forward bite. try to run 4off for wet, 2off for dry-slick on lr. used reverse stagger most of year last year will help tighten up on corner entry. anymore info let me know

jmhkc
Dirt Newbie

Total posts: 1
posted January 23, 2002 12:57 AM
I had a 97 K-mod just like yours. Could drive it deeeper into the turns than almost everybody but always got passed coming off corner. Asked builder about same questions as you have asked here. He said car was designed differently than current thinking. It has more of an asphalt, low center of gravity design. We had to run 1 and 2 inch offset wheels on ls to get car to work right. Car doesn't respond as well to current methods because of design. Newer cars have higher cg and narrower rears and a bunch of newer tricks. Work with either Kosiski's or Bill LaFollette but not both at same time. Bill built car but Kosiski's name is on it. All our spring rates were higher than you ran.

jonboy
Dirt Roller

Total posts: 17
posted January 26, 2002 07:41 PM
The K-Mod is an excellent chassis, but they have a lower center of gravity like an asphalt car. If you try to adjust it with conventional dirt thinking it won't work. The reason the springs are stiffer on the front is because of the spring being in the center of the a-frame (camaro) as opposed to the metric with the spring further out. If you soften the springs there is nothing to transfer weight because the mass is so low. The stiff springs transfer the weight. As far as loose going in, move the J-bar to the right side and lower it to get more weight tranfer to the right rear. Also run the maximum offset on right rear (just clearing the spring). This should tighten the car up on entry. You can work backwards from there. Hope this helps.

neverenoughbrew
Dirt Full Roller

Total posts: 56
posted February 13, 2002 07:26 PM
4-link or z-link, if ya gonna clamp it ya might as well run a 2-link. I think the trend is monkey see monkey do. Hey, the more links the better right? Saw a Post months back talking 'bout 6 links. Add brake floaters ya got 8 links, gotta be fast.

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