Stupid questions??

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Stupid questions??

Postby chevhellion » Sun Feb 22, 2009 8:25 pm

Hello ,newbie here,I have run street cars before(stock suspension skinny slicks)I picked up a 4 link backhalfed car with a stock front clip.What is the use of front adjustable upper a-arm stops,obviously this limits the droop of the front suspension but why would I want to limit that? also on top end the car wants to pitch slightly from side to side not alot but enough so the first run I made in the car I got out of it before I should have,the next few passes it still did it but I just got used to it and stayed in it,I checked all front end and rear hiem joints everythings tight,maybe I'm just not used to running on the bigger slicks ?14x33x15, my helpers said they didnt notice it moving on top but I sure did
I bought this car complete but didnt get much setup info from the owner.
Its basicly a 2900pound car,runs 6.50-6.80 in the 1/8 with a 1.38 60ft. I was footbraking the car but next time out I will be transbraking
thanks for any info!
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Postby pro70z28 » Sun Feb 22, 2009 10:02 pm

The more travel the front suspension has the more it will throw the wt. to the back tires. (Weight transfer). So, you can use that limiter to control how much wt. transfer you need.

Is the car doing the "pitch' thing just on the top end or off the line also?
nothing to say at this time.
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the wiggle

Postby chevhellion » Sun Feb 22, 2009 10:55 pm

it just does it on top,takes off strait wheels about 3" off the ground,I'm sure it will be a bit more radical leaving off the transbrake,it has a 5800 converter but the car wants to move around 3000 on the footbrake
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Postby Billy Mac » Thu Mar 05, 2009 5:51 pm

That is kinda typical "movement" for a converter. They will always start moving the car quicker on the footbrake rather than on the tranny brake.

Does the car have an anti-roll set up on the rear? (either in front of or behind the rear axle C/L) If not, THAT could be some of the roll you are experiencing.......another thing to think about....are YOU about the same size as the previous owner?.....If you are larger OR smaller than the previous owner, then you need to take the car to a chassis shop and have it weighed and scaled to YOU.....Hope this helps.
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wiggle

Postby chevhellion » Thu Mar 05, 2009 10:42 pm

Billy Mac wrote:That is kinda typical "movement" for a converter. They will always start moving the car quicker on the footbrake rather than on the tranny brake.

Does the car have an anti-roll set up on the rear? (either in front of or behind the rear axle C/L) If not, THAT could be some of the roll you are experiencing.......another thing to think about....are YOU about the same size as the previous owner?.....If you are larger OR smaller than the previous owner, then you need to take the car to a chassis shop and have it weighed and scaled to YOU.....Hope this helps.
Do you mean a rear swaybar or are you talking about a panhard bar?,it doesnt have a swaybar or a panhard bar, the rear is located with a paralel link from lr to rf of the rear trailing links, the previous owner was about 5'5" 145lbs I'm 6'2"300lbs so theres a BIG difference there
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Postby pro70z28 » Thu Mar 05, 2009 11:03 pm

The anti-roll bar Billy is talkin' about looks like this.

Image

Keeps the caah from rollin' over on it's side under power.
I don't have a clear shot of the anti-roll bar but it's connected to those hiem joints on top of the rear end housing.

Image
nothing to say at this time.
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Postby Billy Mac » Thu Mar 05, 2009 11:08 pm

Thanks Gary!! (<grin>)


The bar you are describing is the "track locator" (that keeps the rear end centered in the car.) (the bottom pic above also shows a "wish-bone" style locator....it "does" the same thing as what is under your car now...it just "looks" cooler)

A 4 link car also likes to have an anti roll (as shown above).
It attaches to the frame rails AND the rear end housing, with heim ends and short bars to either side of the center section (both sides).....it can be adjusted to hold some preload in the rear suspension as well as keeping the body square and level......
With the size difference between you and the previous owner, I HIGHLY recommend you haveing this car scaled to YOU.
How is the leg room and head room in the car??....Does the seat need to be moved down and rearward for you to be comfy??.....Comfort is a BIG deal when you get to going faster...and you KNOW you want to :wink:
Last edited by Billy Mac on Thu Mar 05, 2009 11:19 pm, edited 1 time in total.
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Postby pro70z28 » Thu Mar 05, 2009 11:16 pm

I went out to the shop and tried to get a little better angle. It's a little crowded back there so this is as good as it's gonna;' get.

Image

pay no attention to the dust of neglect. :oops:
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Postby pro70z28 » Thu Mar 05, 2009 11:20 pm

Your welcome :D
nothing to say at this time.
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Postby chevhellion » Thu Mar 05, 2009 11:21 pm

I allready moved the seat,I couldnt even get in the car the way it was,the bar in the pics is basicly a swaybar I guess, that would probably keep the back end in check,I didnt realize people were using them on drag cars,the bar must be a fairly stiff rate being so narrow. I think the best way to describe the movement is like when your towing a trailer and it starts to sway
Thanks for the info
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