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View Full Version : Fairbury rear suspension - hot setup?



Racin_G73
01-23-2011, 10:19 PM
I'm running a 10-year-old DirtWorks at Fairbury. I'm just a back of the pack "super-rookie" with about 17 nights of racing, total. My current rear suspension has z-link on both sides - the Jeff Martin z-link. And maybe that worked for him, but I don't think anyone else at Fairbury is running it.

I'm thinking of switching over to 4-bar on the left and keeping the z-link on the right. Putting a 4-bar on the right would require a bit more construction as there's no place to weld a bracket right now. Also, I don't know too much about putting springs ahead or behind the rearend, clamped up, etc.

Right now I believe both springs are mounted to the birdcage just ahead of the rearend - not on the forward bar from the z-link (which would make it a sort of swingarm, right?)

So... any Fairbury drivers or crewmen willing to point me in what they think is the right direction? Or at least tell me what they see more of among front-runners?

I appreciate any opinions and will also be looking to my speed shop for their take on it.

racin6mod
01-24-2011, 05:57 PM
I don't run fairbury but my brother has a dw we run the lr clamped up with a coilover shock kit,the rr has the z-link set up with the spring on the axle tube. we are planning on running 4 bar on the rr also. you can pm me for more detailed info.

CC28
01-24-2011, 09:46 PM
Get your seat time and when your ready to be competitive get a new one. Its not even the same ballgame as it was 10 years ago.

coleman63
01-25-2011, 12:56 PM
Racin G73, check your pm's.

Racin_G73
01-25-2011, 04:47 PM
Hey, coleman63: I tried to write back to you but your Inbox is full.

I'll try to send it to you over on Facebook.

nobodyracing
01-27-2011, 01:47 AM
go spring be hind on lr. to looooos in clamp up. is car dw8 or whats it doing

Racin_G73
01-27-2011, 04:53 PM
It's an old DW8, under-rail, z-link on both sides.

My only 'problem' (aside from lack of experience) is that it pushes on exit of turn 2. But I've been told - and can see from Google Maps - that the track is tighter on exit of 2 than it is on the exit of 4.

My hope is that if I move to a setup more like what everyone else has then I won't be out to lunch when the track goes from tacky to dry slick, etc. Right now, I've been getting little bits of advice from a couple people. But it's all their best educated guesses. Since nobody is running the same or even similar setup, they can't tell me "I tried this and it did what you're trying to do."

Know what I mean?

nobodyracing
01-27-2011, 06:55 PM
push off when track dry slick

nobodyracing
01-27-2011, 06:58 PM
is lr spring in bottom bar or birdcage

Racin_G73
01-27-2011, 10:34 PM
Technically, it pushes from middle of turn 1 and 2 through about 2/3 of the way through turn 2. I feel like I can't get back into the gas till the car grips and turns. I can force it to turn by goosing the gas, but that's not quite ideal.

This happens during heat races mostly, so more when the track is a little tacky but not 'wet'. In dry slick I tend to spin out in the middle of the corner if I don't change anything.

The springs are both mounted off the birdcage in front of the rearend. Here's a picture of the left rear. Both the shock and the spring (eliminator) attach to the birdcage in front of the axle.

http://www.racing73.com/Photos/2010_0502/DSCF0711a.jpg

nobodyracing
01-30-2011, 08:27 PM
you say shocks + springs are off birdcage?

bittight
01-30-2011, 09:15 PM
I know on the Jimmy owens swing arm cars, if you run much rebound in the front shocks and its not slick you will b tighter than all get out on the gas initially..Not sure where you are on shock #s or even if it works like that on that brand car but if track blew off we would put on the tiedowns across the nose and that thing would rip up off the corner across the slik!!! I guess that probably would depend alot on the pullbar you have to, and if its trying to pick up the nose thru the pb or let the shocks pop up the nose.. Also what is going on with your rear end dampner shock swing arm seemed to be touchy in that area too..jmo Are you running the biscuit style j bar it looks as tho you are from the pic I cant tell really well but we tried that also and didnt have much success..there is alot to play with on a swing arm I personally do not like chasing them all night never seemed consistant to me from track to track. We changed it over to spring behind 4-4 and the car was much much easier to tune..

Racin_G73
02-04-2011, 08:37 PM
Let me make sure I'm not misusing the term 'birdcage'. Both the shocks and coilover eliminators are mounted to attachment points that are hooked around the axle tube, the slider is mounted just inside the sleeve where the z-link bars attach, and the shock mounts just 'outside'. I'd have to go under the car and study it real good or take some pictures to make sure I'm communicating clearly. But the pic I posted earlier should give you some idea, like you can see where the bottom of the shock is attached just inside the left rear brake caliper.

I've got the Afco J-bar with two rubber biscuits in it. Also have a pullbar(?) from the top of the rearend to the center of the chassis with some more rubber biscuits. On the left front I've got an Afco 1075 - which is a '5' for compression and rebound. On the right front I've got an Afco 1276-4. I believe that's 6 for compression and 4 for rebound but I could have that backwards. In pictures of the car going down the straightaway, the whole chassis really 'squats' both front and rear. Not sure what it does in the front when I enter the corner. But in the middle of the corner it seems to be rolling over in a fairly controlled fashion - not too much, not too little, as far as I can tell. The wraparound shock is an Afco 1279-1 - a typical 90/10 shock.

I'm leaning towards 4-bar/z-link only for ease of mounting the brackets. We'll see how far the budget (and schedule) will stretch before mid-April!

Thanks everybody for all the ideas and information.