Car jumping straight to the right.

Old 01-31-2010, 06:06 PM
  #1  
andybyrd
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Default Car jumping straight to the right.

I'll try and keep this as short as possible, Last week I took my car to the track 1st run it came up and set down about 60 feet out but it was way to the right. 2nd run it came out but this time it sat down about 60' to the left, 3rd run same thing 60' to the left, all 3 runs I came out @ 4000rpm on the brake, 60' was 1.36 now all last season it was comming out perfectly straight. now I changed rear gears from a 5.14 to a 5.67 because I was only getting 6200 rpm at the 1/8 and my H/P max is 6700 so I wanted to see what it would do with this gear, all the calculaters shows the 5.67 to be the best gear for the 1/8 with 32'' tires with my setup. But WOW that 5.67 brings the front end up higher just foot braking it than the 5.14 did comming out at 4000 with the Trans brake, But anyway getting back to the point. I can't drive it with the 5.67 because man that gear change just amplified my pulling problem. I could drive out of the pulling let or right with the 5.14 but the 5.67 allmost made me wreck it twice so I put it on the trailer. Now my panhard bar braket that bolts through the front of the left side ladder was loose last week so I tightened it up before I took it out this weekend but that didnt do anything.
85 camaro
1.76 PG
2500#
670 H/P - 434 sbc
9''ford 5.14
14 x 32 M/T
5000 coan converter
ladder bar w/Alden American coil overs
6.09 - 112 mph @ 6200 rpm 1/8 mile

Thanks Guys I could'nt put all the details in and keep it short, sorry and I bet I still missed something.
ONE thing more would you run the same amount off air in a tire with or without a tube?
Thanks Again Andy
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Old 01-31-2010, 06:49 PM
  #2  
TheYellaBrick
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Are you running a spool or a clutch type posi ? If a posi, it could maybe need new clutches.

Check-check-and double check your diameters on both tires with the same air pressure in both. If you are even 1 to 2 pounds off of equal side to side, it will change your rollout / diameter drastically and pull to the 'shorter' side like crazy,especially with just the drive tires on the ground and running a spool.
In circle track in the street tire divisions, you can put in a ton of wedge just by air pressure differences side to side.

Have you 'squared' the chassis and suspension points ? If that rear axle is off a tiny bit it'll pull.

But you did say that it wasn't consistently pulling to just one side, didn't you so all the above is not relevant....
ops: ops: ops:

Just a thought,.. How long is your panhard bar and how much actual rear suspension compression do you get during launch ? Too short a panhard with a lot of suspension compression wil move the rear end in a severe 'arc' hence side to side movement instead of straight and in line with the chassis.
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Old 01-31-2010, 07:22 PM
  #3  
andybyrd
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well the first time last weekend it pulled out hard to the right but every time after that it went left, I made sure the pressure was the same 8#, the roll out is the 100'' in both tires. It does have a spool. and now that you mention it it got worse when I tightened up the panhard bar brackett, it was loose. but I did that at the same time I changed the gear so I don't know what made it worse, I know this much, last week I just drove through it with the 5.14 but with this 5.67 it SCARED the sheet out of me and mife wife got mad and left
Thanks Andy
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Old 02-01-2010, 09:25 AM
  #4  
TheYellaBrick
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Is it jumping at launch time or is it a smooth transition of power to the tires ?
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Old 02-01-2010, 10:00 AM
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andybyrd
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When you hit the gas it comes up and out to the left, from the right lane, when it comes back to the ground its in the left lane. about 60' out. and thats foot braking, one thing I just thought about, last week I had my wheelie bars on and this week when I changed the gear I just left them off being I was just gonna foot brake it I didn't think it would come up that high, so last week it may had been just as bad but the wheelie bars was keeping it down so it could'nt go so far to the left, I'm lost now I don't know what else to do other than take it to a shop and let them figure it out.
Andy
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Old 02-01-2010, 11:51 AM
  #6  
zipper06
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If there's someone in your area that has scales, i'd have them scale the car. My car used to go sky high and either go left or right. My is a 4 link car though.
I had a friend/builder scale the car set the CG and preload, bettered the 60' by .003/.004 and only picks up the left front about 4" now. I don't even need the wheelie bar now .543 gear, 14X32's leaving @ 4200 on brake with a 5500 stall converter, car weighs 3253 lbs.
Cost was $250.00 for the whole setup and well worth it.

JMO

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Old 02-01-2010, 06:16 PM
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andybyrd
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Thanks Zipper and Driving,ms D, I have set up an appointment with a frame guy to scale it and check it out because it is just to scarry for me to try and fix I can't even drive it now. It will take me into the wall that quick.
Thanks Andy
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