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Author Topic:   chassis setting
keith24kracing
Dirt Newbie

Total posts: 4
posted October 21, 2002 08:04 PM

i was wondering if anybody uses a wheel load checker like the one in speedways book to set your car up.i bought my car used and never had it on the scales.

sixwillwin
Dirt Freak

Total posts: 215
posted October 21, 2002 11:51 PM
Dont waste your $$$ on one, I had one and sent it back after I tried to use one time.

powerglides
Dirt Full Roller

Total posts: 69
posted October 22, 2002 10:30 AM
Same here. Checking wedge by jacking under pumpkin is as good as those things.

loojack
Dirt Maniac

Total posts: 133
posted October 22, 2002 03:46 PM
Keith, Might want to go to the tool box and look at the scale plans, I built a similar set and they work pretty well. Good luck and have fun!!

66jj
Dirt Freak

Total posts: 352
posted October 22, 2002 09:37 PM
i have electronic sclales and a pogo stick i made and use both..

kthe key with the pogo stick is to lift it the same ht every time, i use just enough to slide a piece of cardboard under the tire. this takes a 2nd guy..

i made my own pogo stick with a torque wrench as the handle, the kind that has a pointer and pts at the torque.. all you need is to weigh your car once with electonics and pogo a corner to see what torque # equals actual weight..

one half in socket and a cheap wrench and about 3 ft of tubing and you can make one easy, i adjusted the lever ratio till i got to a even torque # like 10 lbs equals 100, it wont get too specific, but its all your budget..

c21
Dirt Freak

Total posts: 346
posted October 23, 2002 11:23 AM
That sounds like a pretty clever set-up 66jj.

I think it should be pointed out that any info obtained from a "pogo stick" (or scales for that matter) is useless if not gathered with the car sitting in the exact same place everytime (or on perfectly level ground everytime)..... a 1/4" diffence in ground level at one corner can throw your cross calculation off by more than 1% !!

I think 66jj's method of verifying the amount the tire is lifted with a peice of cardboard is great.... but if the car is not sitting at the same level (at all 4 corners)as it was last time it was checked with the "pogo" or scaled... the info is nearly useless.

as an example: I had a really bad crash (roll)2 weeks ago on the first night of a 2 day open show, 300+ miles from home (without my scales). After replacing some bent front end peices (spindle, balljoint, etc.) we decided to use the nice set of Longacers the track had set up on a pad poured specifally for scaling. I found the cross was off by 4% (which came as no huge surprize concidering the severity of the crash (and my lack of a spare lower A to replace a slightly bent one) so.... we adjusted it back to the 52.6 I was planning on using in the main.

The car was hard to drive (figured there were unresolved issues from the previous days crash) and pushed faily hard in the middle (gobs of forward bite though).
Decided to scale it agian the next day when we got back to our shop (set-up as scaled the previous day at the track) and found the cross to be 56.5% !!! guess that explains the push. .... anyway we took out the weightjack changes we had made at the track and it came bake to 52.4% ! so if I had left it alone, I would have been off by 2 tenths of a percent rather than the 3.9!

The Moral might be don't adjust you car to death, just run it ...or .... becareful using unknown measuring devices (or measuring on unknown surfaces)

c21

eborcim
Dirt Full Roller

Total posts: 46
posted October 23, 2002 11:40 AM
I can't remember, which side do you want to raise when you check the wedge?

loojack
Dirt Maniac

Total posts: 133
posted October 23, 2002 03:16 PM
Wedge or cross weight is right front to left rear. Hope this helps! loojack

outlawstock17
Dirt Forum Champ
Total posts: 620
posted October 23, 2002 05:32 PM
to check your wedge or crossweight "po' boy" style, use a big 1/2" drive socket on the saddle of your floor jack. lay the socket down so it is free to roll from side to side. center the socket on your rearend housing and jack the car up. the RR should lift off of the ground first, followed by the LR. i have a short wheelbase car(99"), so i need more crossweight than a 108" car. a 108" car should have about 1 1/2" difference between the heights of the 2 rear wheels. for example: the RR should be 1 1/2" off of the ground when the LR is just barely touching the ground.

this is just a baseline setting and your driving style may need more or less.

hope this helps.

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