dropped spindles?

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prodart340

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hi everyone,anybody know of any place that I might be able to find a set of dropped front spindles for a 74 dart?
 
fat man fabrications makes drop spindles for the street rod world,,also has a list of dropped spindls for mopars,,but you dont need drop spindles on a 74 dart,just lower the torsion bars,

www.fatmanfab.com
 
FWIW, I wanted to retain more suspension travel on my Duster so I went with the Fatman spindles. Not cheap but they work well. You can see them on my site (below) by clicking the "Chassis" link.

You may be happy just doing what fstfish66 suggested. Most people do.
 
:notworth:70duster440......you are the man!!!! I've already been the route with the "loose" torsion bars, that didn't get it. When I tubbed the car,I too dropped the rear for the exact same reason. Thanks By the way,what did the kit cost?:notworth:
 
I spent in the neighborhood of $500 for the pair. I did a little grinding on each for some clearancing. Right now Fatman is about the only option. I believe Firm Feel has been working on a modified lower control arm to do the same thing. And, there's a company in Australia that makes a drop spindle but they're pricier by the time you'd get them.
 
My K-frame already scrapes the ground on shallow dips. Why would I need it to travel another 2" lower?
 
Because you have no tension on your bars, when you put drop spindles in, you can preload the bars, and it will not bottom out so easily any more. Thus same ride height, just a little more firm.
 
Cageman said:
Because you have no tension on your bars, when you put drop spindles in, you can preload the bars, and it will not bottom out so easily any more. Thus same ride height, just a little more firm.
Click to expand...

Spring rate is spring rate. It stays the same where ever you set the ride height. The amout you turn the t-bar adjuster (what you are calling preload?) just changes the ride height. Just like adding a spacer or turning a screw jack in a coil spring car.

If you put a 1" spacer on top of a coil spring, then compress it 2" travel the rate is the same as compressing a spring 2" travel without the spacer.

The reason the dropped spindles don't bottom out is that the lower control arm bump stop is further away from the frame stop on the car.
 
the question is, where does the roll center wind up?

do the dropped units move the centerline of the stub axle or is the difference at the ball joint?

realistically, the ideal would be a modified LCA for a lower ride height...

-JYH
 
Twist a torsion bar at stock ride height, it will twist more and have more resistance to twisting the more you do it. I think it is called linear spring rate. Now lower the car with the torsion bars, it has less preload into the bar, as it doesnt have to lift the car up so high any more, the control arm is a lever. Now you also take away travel, so it will not go through the amount of twist the drop spindle or normal ride height would allow, so that is why it helps. I hope I explained my point, I am not good at explaining, and it is late.
 
what does modifying a lower do for you then? preloads the torsion bar more.
It cant do what a coil car does, as the spring sits in the lower, A torsion bar has the spring and lowers' pivot at the same place.
I have indexed my torsion bar mounts before to get them to allow more preload into the torsion bar, other wise I bottomed out every corner.
 
autoxcuda: "Spring rate is spring rate. It stays the same where ever you set the ride height. The amout you turn the t-bar adjuster (what you are calling preload?) just changes the ride height. Just like adding a spacer or turning a screw jack in a coil spring car."

Unless I misunderstand you - quite likely - that can't be true. With any spring the more you twist it, the more resistance it returns ... until it breaks. While a spring might be "fairly" linear in resistance for a certain spread, at it's lower limit it must be lighter and at it's upper limit it must offer greater resistance. Otherwise it would either constantly bottom out or break.
 
You aren't twisting the bar more when you turn the adjuster you moving the bolt thread bracket attached to the LCA because you are threading the bolt in or out. The bolt seat is part of the torsion bar arm so it stays stationary. If the bar twisted more then the car would stay the same height. The car raises because the bar doesn't twist more. When the car is at rest only more or less weight will make the bar twist more.

Chuck
 
dartley said:
autoxcuda: "Spring rate is spring rate. It stays the same where ever you set the ride height. The amout you turn the t-bar adjuster (what you are calling preload?) just changes the ride height. Just like adding a spacer or turning a screw jack in a coil spring car."

Unless I misunderstand you - quite likely - that can't be true. With any spring the more you twist it, the more resistance it returns ... until it breaks. While a spring might be "fairly" linear in resistance for a certain spread, at it's lower limit it must be lighter and at it's upper limit it must offer greater resistance. Otherwise it would either constantly bottom out or break.
Click to expand...

The spring rate is linear. Meaning the force required to go from 1" to 2" of travel is the same additional force to go from 2" to 3" of travel. The rate of change is the same.

Of course it takes more and more total force as the spring is pushed. Add the 1" to 2" force to the 2" to 3" force and you have the total force.

When we check spring rate for our circle track car we compress the spring set distance for every spring, then zero the force gauge, then compress the spring 1". That reading is the spring rate; pounds per 1 inch. (lbs/in).

It's just following the elastic curve on the materials tension graph. In the elastic region the curve is flat and the rate of change is constant.
 
"If the bar twisted more then the car would stay the same height."

Respectfully, that's just ridiculous. When something pushes the wheel up into the wheel well the spring comes under greater tension because it is twisted more.
 
autoxcuda said:
The spring rate is linear. Meaning the force required to go from 1" to 2" of travel is the same additional force to go from 2" to 3" of travel. The rate of change is the same. Of course it takes more and more total force as the spring is pushed.

It's just following the elastic curve on the materials tension graph. In the elastic region the curve is flat and the rate of change is constant.
Click to expand...

Okay, that's basically what I said, but with a bit more detail. So, what is the "elastic region" of these torsion bars? I doubt it's very much since the bars themselves don't twist very much.


PS: BTW - I remember reading your page some years ago when you were apparently in the midst of deciding whether to go with a bigger front A/S bar and add a rear one, or stay with only the front A/S bar of smaller dimension. What made you finally decide to go the former route ... pure performance numbers, better driveability, better transitions, what?
 
dartley said:
"If the bar twisted more then the car would stay the same height."

Respectfully, that's just ridiculous. When something pushes the wheel up into the wheel well the spring comes under greater tension because it is twisted more.
Click to expand...


If the car is at rest and you turn the adjuster bolt and the bar twisted more then the car would stay the same height because the bar would be taking up the movement of the bolt being turned.

If the bar doesn't twist more when the bolt is turned then the car body will move because it is taking up the movement of the bolt being turned.

Now when the car is moving or going into a turn yes the bar will twist more because the load has changed on the bar. But sitting still the only way to get the bar to twist more is change the weight on the car.

You can believe it or not but it is simple physics.


Chuck
 
340mopar said:
If the car is at rest and you turn the adjuster bolt and the bar twisted more then the car would stay the same height because the bar would be taking up the movement of the bolt being turned.

If the bar doesn't twist more when the bolt is turned then the car body will move because it is taking up the movement of the bolt being turned.

Now when the car is moving or going into a turn yes the bar will twist more because the load has changed on the bar. But sitting still the only way to get the bar to twist more is change the weight on the car.

You can believe it or not but it is simple physics.


Chuck
Click to expand...

Chuck when I said respectfully, I meant it ... I did not intend to cause any insult.

Next I did not mean to but I suspect I took you out of context. I was responding you the part of what you said that I quoted specifically, having nothing explicitly to do with the adjustment mechanism on the car.

That said, I choose not to believe your explaination - it does not make any sense to me, oh well.

PS: "simple physics" is an oxymoron - that's why rocket science is what it is.

Best regards,

~Bill
 
dartley said:
Okay, that's basically what I said, but with a bit more detail. So, what is the "elastic region" of these torsion bars? I doubt it's very much since the bars themselves don't twist very much.
Click to expand...

The elastic region is those whole spring movement just about until it breaks. Just before it breaks, the spring will not go back to it normal position it will be permenently deformed and changed. Depending on the kind of steel and treatments.

The elastic region for our T-bar would go way beyond where the bump stops on our cars are. So it all falls in the elastic region of that metal.


PS: BTW - I remember reading your page some years ago when you were apparently in the midst of deciding whether to go with a bigger front A/S bar and add a rear one, or stay with only the front A/S bar of smaller dimension. What made you finally decide to go the former route ... pure performance numbers, better driveability, better transitions, what?
Click to expand...

I added rear bar with a stock front bar. Good for autocross and gets the car to rotate. Fine on the street.

Now just before I went out to willow springs race track this May I added a front 1 1/8 sway bar. The professional instructor, Bob Reed with the badass handling red 68 Cuda that's been in Car Craft, drove my car and said he thought it still had too much rear bar and he'd not run the rear bar. That's on my specific car. But he did say with his personal driving style he didn't like much rear bar/roll couple.

I think it's safe to say I made a good choice adding the front 1 1/8 sway bar before I went out on the road course.

But again, I've added front QA1 shocks. I'm playing with those now. That might change things.

I think in an autocross, slower speed, tighter course situation more rear roll couple is needed than a road course.
 
autoxcuda said:
The elastic region is those whole spring movement just about until it breaks. Just before it breaks, the spring will not go back to it normal position it will be permenently deformed and changed. Depending on the kind of steel and treatments.

The elastic region for our T-bar would go way beyond where the bump stops on our cars are. So it all falls in the elastic region of that metal.




I added rear bar with a stock front bar. Good for autocross and gets the car to rotate. Fine on the street.

Now just before I went out to willow springs race track this May I added a front 1 1/8 sway bar. The professional instructor, Bob Reed with the badass handling red 68 Cuda that's been in Car Craft, drove my car and said he thought it still had too much rear bar and he'd not run the rear bar. That's on my specific car. But he did say with his personal driving style he didn't like much rear bar/roll couple.

I think it's safe to say I made a good choice adding the front 1 1/8 sway bar before I went out on the road course.

But again, I've added front QA1 shocks. I'm playing with those now. That might change things.

I think in an autocross, slower speed, tighter course situation more rear roll couple is needed than a road course.
Click to expand...

You mean that on the tighter autoX you don't want to tail out as much? ... I can understand that. I'd say that with that stock front bar and the addition of the rear bar you must have been near tail happy - makes sense that you'd need a bigger front bar in that case. I've found one downside to the heavier front bar "on the street" (read: potholes and pavement cracks) is that, since the front wheels are "tied" together more, the car seems to get dragged around more than before - if one wheel moves alot the other side is more likely to follow in that direction ... similar to what happens when the rear steps out over bumps, but obviously not as badly.

I've toyed with the idea of going back to a stock front bar, no rear bar and heavy torsion bars instead, but I probably won't actually go and do it, if only because my settup is pretty nice for what I use it for and time is a bit tight.

Nice chatting with you though,
 
Another possible problem with a bigger sway bar is that it tries to pick up the inside tire which can lessen traction on a car if the bar is on the drive axle end of the car. If the car has an open diff it really becomes a problem.


Chuck
 
dartley said:
You mean that on the tighter autoX you don't want to tail out as much? ...
Click to expand...

No, in a tight autox you want the tail loose to help turn that heavy beast between those cones. And your are under 60 mph so it's more forgiving if it gets unstable.

I can understand that. I'd say that with that stock front bar and the addition of the rear bar you must have been near tail happy - makes sense that you'd need a bigger front bar in that case.
Click to expand...

Drove it for almost ten years like that. Wasn't bad at all. I drove it like a madman around town. It's on higher speed corners on a track it's where it would get tail loose.
 
Thanks for the explanation, I just now see that the t-bar stays while the car is lifted, so I can lower the front and not lose spring rate. I never had a clear picture before thanks Chuck and all.
Bruce
 
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