Visit The Dirt Forum for More Information

Author Topic:   Need setup help.
frankthetank
Dirt Full Roller

Total posts: 64
posted July 31, 2005 05:51 PM  
This could turn into a long paragraph but Im trying to give you as much info as possible. My 5th year running a street stock, multi time feature winner, so I dont feel driving is the problem. Always have run a metric car, stock rear suspension. 3200 lbs. Now last year track opened up rules. So over the winter decided to have a new car built from a well known chassis builder on the east coast. Car is still metric frame. Metric front suspension. Shocks are relocated outside of a arms. Rear end is a 3 link. Top arm is solid. Bottom arms are still in stock location on the frame but are heims ends with 3 holes of adjustment on the rear. Has a solid rear panhard bar. That is mounted in the center of the axle tube on the left rear and frame mounted on the right rear. Right now Im running a 1200 pound rf, 1100 lf, 250 lr and 275rr. 20 pounds of lr bite. Car has 4 corner weight jacks. Front is level with the rear being 1 inch higher. Panhard bar is level. 3rd link bar has 14 degrees of angle running downhill from the rear to the frame. 54% left. 50.5% rear. Problem is the car is tight, tight in, tight on throttle then loose off. I started the year with more bite but have decreased it to try loosening it up. Track is strange. Where as the heats seem to be slick as **** , but when the sun goes down the moisture comes up and it tightens up. The thing that is killing me the most I think is the panhard bar. The chassis builder uses this setup alot, and has had alot of success. But he doesnt attend the track Im running regularly so he's making suggestions to me based solely off what I can tell him. How much angle do you run or can someone suggest. Sorry I drug this out but would like to give as info as possible. Thanks

Magic82
Dirt Full Roller

Total posts: 34
posted July 31, 2005 07:15 PM  
Can you tell us what your cross weight is and each corner weight? How about staggers, wheel offsets, shocks? One thing I noticed was that you have a stiffer spring on the rr. How come? How much lr bite have you run and did it not help at all? I currently run around 100 pounds but every car and driver are different.

frankthetank
Dirt Full Roller

Total posts: 64
posted July 31, 2005 07:49 PM  
Cross weight is 46.3% Lf is 933, RF is 673, LR is 837, RR is 815. Run 1 1/2 inches of stagger in the front and around 3 in the rear. I originally was running a 250 in the right rear, but out of desperation to make the car turn i flopped the rear springs and on that particular night it seemed to want to the car a bit better. I run 2 inch offsets on the front, and 4 inch on the rears. The shocks are all bilsteins, 76's on the front and 95's on the rear. It seems when i was running more bite it pushed too so we took the bite out and now we're still pushing. Honestly we're just lost.

sc1 racing
Dirt Freak

Total posts: 419
posted July 31, 2005 08:01 PM  
try softer springs in rear 200/175, and load your panhard bar 30 degrees down to rear end. also what tires, beadlocks, and air pressures are you running?

frankthetank
Dirt Full Roller

Total posts: 64
posted July 31, 2005 08:10 PM  
We're running the American Racer late model tires on a 10 inch wheel, beadlock on right rear, air pressure has been 12 on lefts, 12 on rr and 15 on rf. Being that the panhard bar is on the right rear frame to left rear of the axle housing, Is the highest point on the frame down the axle or from the highest mounting point on the housing down the frame? Does length of panhard bar matter?

sc1 racing
Dirt Freak

Total posts: 419
posted July 31, 2005 08:15 PM  
oh heck its on the wrong side to..

if you are running the late model pull offs. id run
12/16
10/12

and take the panhard off, if you cant get it insalled on the left side of frame.

frankthetank
Dirt Full Roller

Total posts: 64
posted July 31, 2005 08:21 PM  
That sort of answers my question, are you saying the panhard bar needs to be on the left side of the frame? Is that hard to get it to work on the other side? Could this be some of the problem?

sc1 racing
Dirt Freak

Total posts: 419
posted July 31, 2005 10:04 PM  
i dont know why it wont work but it will on asphalt, and i have no idea what works on asphault. you can run with out it. but it deffinatly needs to be mounted on the left side of the frame.

Eljojo
Dirt Forum Champ
Total posts: 968
posted August 01, 2005 04:35 AM  
With the information you have provided, I would have to suspect that there is an alignment problem with the rear end. The low crossweight combined with the softer spring in the LR, the chassis should be very very loose.
I constructed a set of wheel stands that would allow me to set my car down on all four tires and hold it securely about a foot off the floor. This allows me to view the suspension while loaded. (not me-the car)
Then I can raise the left of the car and see what takes place as the the suspension travels. I strongly suggest you set your car up and do the same. You may find tha the panhard is pulling the right rear tire forward or pushing the left rearward. what is level at static may turn out to be dramaticly different as the chassis goes into roll.
I know I do a lot of "caveman" engeneering, but I generally find those "kinks" that prevent the chassis from functioning as it should.
I have seen panhards tied to the frame on eith the left or the right side and work on both dirt and asphalt. The side that it is tied to affedts the rear roll center movement during chassis roll.
keep us posted.
JoJo

    

Back to the Archives