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Old 12-01-2004, 01:29 PM
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Explain your spring theory.


On the shocks you are claiming that the shock can control wheelstands just by tightening the shock???? I was just curious about this because since 1997 and my first wheelstand on these torque arm cars tightening the shock never killed the wheelstands. The only way controlled them was to limit travel AND run softer springs.

I'm always open for other theories.
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Old 12-01-2004, 01:41 PM
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I am no expert in physics or anything but, it does seem like a stiffer rear spring would help prevent wheel stands. The stiffer spring seems like it would take longer to compress allowing the car to get moving first. I would think a softer spring would allow quicker weight transfer and more room for the rear of the car to come down.
Old 12-01-2004, 01:47 PM
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The body does not squat. It tries to separate from the rearend. Yes you can have too much spring in the rear.

I'm not an expert. Everything I have learned is from hands on experience from countless passes in my cars and customers.
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Old 12-01-2004, 03:17 PM
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i am talking about the front suspension.

as far as the dampening of the front shocks/struts...i am talking about my mustang. my camaro doesnt make enough power to lift a wheel ...so if its different with fbodys for some reason...forgive me.

but my car on motor...with my koni's as loose as they will go...will pull the front tires off the ground about 1'. now when i spray the car, i adjust them as tight as possible, and if i run like that on motor, the front tires wont come off the ground at all....and when sprayed they come up about 1-2ft. if i were to spray the car with them all the way loose...the car would flip over backwards. so in my eyes...dampening "can" control wheelies to point.
Old 12-01-2004, 03:19 PM
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Originally Posted by MADMAN
The body does not squat. It tries to separate from the rearend.
Isn't the body squat look from the shocks pulling the body down to the rearend? Am I correct? Won't a stiffer spring just let the rear tires force into the track harder.
Old 12-01-2004, 03:41 PM
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slowhoe you are correct to a point. On your mustang the strut helps alot

z28racer you are also correct.
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Old 12-02-2004, 01:47 PM
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So you are saying if you have no problem hooking, just comng up to high go with a softer spring in the back?

And if you have traction issues a stiffer spring would help?
Old 12-02-2004, 01:53 PM
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Originally Posted by andy98Z
So you are saying if you have no problem hooking, just comng up to high go with a softer spring in the back?

And if you have traction issues a stiffer spring would help?
I think he is saying run a softer spring up front since the rear springs don't effect weight transfer after you let off the brakes.
Old 12-10-2004, 04:37 PM
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I run all stock springs, but I can't pull a wheelie.
Old 12-13-2004, 01:22 PM
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Does anyone have pictures or a list of parts use in setting up the upper mount for a 2.5 inch rear spring setup? This sounds like a great idea and if the upper mount can be adjusted up and down you could really fine tune the spring rate preload and ride height. If anyone has any info and or pictures on this I would be great full
Old 12-13-2004, 01:32 PM
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Call me and I can give you some ideas. 281-290-8899
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Old 12-13-2004, 02:01 PM
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Originally Posted by slow3hoe2
a soft spring and a hard spring have the same amount of stored energy when the car is at ride height.
hmmm...I have to disagree...

Stored spring energy is the area under the curve if force vs compression is plotted. Since we are using linear springs...this curve is a triangle.

Since the force is constant (front vehicle weight), then

stored energy = front vehicle weight * spring compression / 2

spring compression for a softer spring will be higher since more compression is required to build force.
Old 12-13-2004, 03:46 PM
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Originally Posted by Fireball
hmmm...I have to disagree...

Stored spring energy is the area under the curve if force vs compression is plotted. Since we are using linear springs...this curve is a triangle.

Since the force is constant (front vehicle weight), then

stored energy = front vehicle weight * spring compression / 2

spring compression for a softer spring will be higher since more compression is required to build force.
ok..i was a sleep on my desk when they were teaching that in school

i guess what i was saying is that at equal ride heights...both springs are holding up the same amount of weight...therefore they are exerting the same amount of pressure. the stiffer spring will lose pressure faster than the softer spring as they are extended.
Old 12-13-2004, 03:53 PM
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I think best idea is to call Madman.

Ken
Old 12-13-2004, 04:03 PM
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Originally Posted by z28racerlt1
I think best idea is to call Madman.

Ken
yup...so he can tell ya how springs work opposite of the way they actually do.

cuz according to madmans spring theory, ill put some 700 lb road race springs on my ls1 and make it flip over backwards on launches.

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Old 12-13-2004, 04:27 PM
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Originally Posted by slow3hoe2
yup...so he can tell ya how springs work opposite of the way they actually do.

cuz according to madmans spring theory, ill put some 700 lb road race springs on my ls1 and make it flip over backwards on launches.
I'm not getting into the physics of it but I have seen cars that he set up. They speak for themselves.

ken
Old 12-13-2004, 04:42 PM
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Heres a case in point. 1969 Nova with double adjustable coilover shocks in the front. Caltacs and leaf springs in the rear. We had a 450lbs spring on the front and the limiters backed all the way off. The car would 60 ft at a 1.35 and barely pick up the front wheels. At the track I changed the front springs to 500lbs and set the ride height the same. No other adjustments were done to the car. Now the car leaves with the front end 2 ft in the air and carries the tires out to about 50 ft. The car has run consistent 1.29-1.30 60fts.

If this theory of mine didnt work them why did the car change???????
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Old 12-13-2004, 04:59 PM
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interesting
Old 12-13-2004, 05:01 PM
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Originally Posted by MADMAN
Heres a case in point. 1969 Nova with double adjustable coilover shocks in the front. Caltacs and leaf springs in the rear. We had a 450lbs spring on the front and the limiters backed all the way off. The car would 60 ft at a 1.35 and barely pick up the front wheels. At the track I changed the front springs to 500lbs and set the ride height the same. No other adjustments were done to the car. Now the car leaves with the front end 2 ft in the air and carries the tires out to about 50 ft. The car has run consistent 1.29-1.30 60fts.

If this theory of mine didnt work them why did the car change???????
i did the same thing with my mustang...except opposite. had 210 lb coil over springs. COULD NOT leave off the tbrake...wouldnt lift the front end much...changed to 130 lb springs...walla! 2 ft wheelies and dead hookin. this was a hp car that at the time went mid 1.3's after changing the springs...and mid 1.4's before.

I am not arguing about what works better on a particular car. my only point is that a softer spring will make a car wheelie more than a stiffer spring...with both cars dead hooking. that is just a fact. If both cars dead hook with either spring...the stiffer one will probably aid in the better et....but when you have a car thats limited in suspension and tire...compared to the amount of power it has....the softer spring will aid in lifting the front end.

im not mad at anybody or trying to put down anyones knowledge....the only reason i started posting on this subject was because i thought maybe i missed something...and i was not seeing what youre seeing.
Old 12-13-2004, 06:10 PM
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Here's what my local Go-Fast guru told me-

Let's say you have to hold up 1000#
You have a 125# spring and a 250# spring

The 250# spring would compress 4" and the 125# spring would compress 8" for the
same ride height at the same length. correct?

When launching, the 1st inch the 250#spring would be holding up 750# and the
125#spring would be holding up 875#.

so at a 4"rise the 250# spring would be done and the 125# spring would still have
500# of spring left.

So with 500# of spring left,I would think it would do a bigger wheelie then with the
250# stiffer spring (all things being equal in the rear).

I kinda thought the whole purpose of 'Drag springs' was to transfer weight better
to the rear allowing you to hook/wheelie better.

That's why we don't run road race springs at the dragstrip.


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