Significantly lower the front of Dart??

[chris70swinger]

I have a '70 Swinger, and I really want to drop it 2-3" in front, but I don't want it to drive like crap.  The car is a /6 auto, and will remain fairly stock for now.

How much lowering can be done by adjusting the torsion bars?  Does this reduce ride and handling?  How is that done, exactly?

As far as I know, the best way to lower a vehicle without screwing up the geometry is with dropped spindles.  Does anyone make these for A-bodies?

I want to drop it about half that in the rear, I assume it's just simple lowering blocks?

[moparrr07]

fatman fabrication make some but they are quite expensive, you can drop the fender lip of a dart 2 inches below the top of the tire, not sure how the ride would be beyond that

[GTS225]

Lowering the front is easy as cranking down the preload on the torsion bars.  (Big bolt under the center of the lower control arm.)  The only problem is that you significantly reduce your spring rate at the same time, which makes the car drive like crap.  The smart way is dropped spindles.  Second best would be to put in small block T-bars so that you can lower it with the adjuster screws without the drastic reduction in spring rate.

Roger

[moparrr07]

lowering or raising the torsion bars DOES NOT cause the suspension to become harder or softer, it might appear to ride differently because the geometry of the lower control arm is different because its now at a different angle, angled up in this case, for example, in an extreme case, say you lifted the front of you car so much that the control arms were pointed downward at a 45* angle, it would be very hard to compress because you have to push the tires outwards, this is exaggerated but still applies, this is why the ride appear different, if you drop you suspension 2 inches or raise it 2 inches and go and push down, i am positive one will not be harder than the other, but the car will handle very differently for obvious differences in ride hight, alot more effect handling that just spring rate

this is NOT my opinion just simple physics

[69 GTS Clonvertible]

You can lower the front end by the torsion bar bolt adjusters, but it makes your front tire wear unevenly and screws with your front end alignment. I had a 63 Valiant that I did this to when I was a teen and I had to replace the front tires or rotate from front to back more often then usual because of the wear pattern. also it does make the ride more stiff and when you go over a bump it will have a stiff bounce to it. heres a pic of it behind my little sis, those are the stock 13" rims on it I had 14" crager ss rims but had to throw the stockers back on them because of tire wear. By the way it was so low to the ground once I got one of those fix it tickets because the K-frame was lower than the bottom of the rim. Adjusted the bolts back up......... took the ticket down to the court house and had it signed off because it was above the bottom of the rim.............. latter turned them back down............. gave it that racked hotrod look but only had a /6 and 904.

[DartKnight]

Tubular adjustable upper CA's and stiffer torsion bars help a LOT if you are lowering it that far. Go that low on stock stuff, you better have extra tires and ball joints available because they will get destroyed quick.

[scaldeddog]

lowering or raising the torsion bars DOES NOT cause the suspension to become harder or softer, it might appear to ride differently because the geometry of the lower control arm is different because its now at a different angle, angled up in this case, for example, in an extreme case, say you lifted the front of you car so much that the control arms were pointed downward at a 45* angle, it would be very hard to compress because you have to push the tires outwards, this is exaggerated but still applies, this is why the ride appear different, if you drop you suspension 2 inches or raise it 2 inches and go and push down, i am positive one will not be harder than the other, but the car will handle very differently for obvious differences in ride hight, alot more effect handling that just spring rate

this is NOT my opinion just simple physics

I have to disagree with you on this one. You don't "lower" the torsion bars by turning the adjuster nut, you are taking the torsional tension off of them, basically taking the spring load off. You lose suspension travel and have a VERY harsh and bouncy ride. Been there, done that. So while the spring rate will not change, once the tension is off, your just riding on rubber tires.

[chris70swinger]

Well, I called Fatman Fabrication- wow, you weren't kidding about the price- $505 for a pair of drop spindles.  They said they would only work with the 4 1/2" bolt circle, so this also means at the very least I have to convert to discs and the '73-'75 upper control arms.  Time this is all installed and aligned I'm well over $1000, and that assumes no new shocks, no heavier torsion bars, no new sway bar.  And that still leaves me with 4 1/4" BC on the rear...

I can't believe it costs that much! 

[doug 371]

i would have to agree with scaldeddog

[375InStroke]

I have to disagree with you on this one. You don't "lower" the torsion bars by turning the adjuster nut, you are taking the torsional tension off of them, basically taking the spring load off.

This would only be true if the car was supported or the control arm was prevented from moving.  With weight on the suspension, when you turn the adjuster, the rear torsion bar anchor is fixed, the front pivot with the adjuster arm doesn't move, but the control arm rotates around the pivot shaft housing.  What you said does start to apply once you reach the bump stops, and you get the bounce you talked about.  Lowering does change the geometry, but so what.  That isn't really a bad thing.  It lowers your instant center and gives more and faster camber gain in rebound.  If you want to go really low, and want the car to corner better, get stiffer torsions, and cut the lower bump stops to about 3/8" thick.  For your alignment, a carpenters square against the tire will show you the camber.  1/4" in at the top of the wheel compared to the bottom of the wheel would be about 1 degree negative.  A tape measure and plumbob get the toe-in, and if you want to know caster, let me know.  It's a bit more complicated, but a tape measure and carpenter's square is all that's needed.  As my cars are now, with stock spindles, my K-frames hit the ground sometimes on rough Seattle roads.  What would happen with dropped spindles?  I'd have an extra 2" of travel, but what good is that once the K-frame's dragging the road?

[Bakaruda]

There are some good points here. It is my opion that the cheap way to do it is. Use tubular upper arms and move the bars. Then get it alligned and tell them not to raise the ride hight. This is the cheap way to do it. The way I would recomend is the fatman arms and the upper arms. Then set the ride and get it alligned.

[moparrr07]

I have to disagree with you on this one. You don't "lower" the torsion bars by turning the adjuster nut, you are taking the torsional tension off of them, basically taking the spring load off.

This would only be true if the car was supported or the control arm was prevented from moving.  With weight on the suspension, when you turn the adjuster, the rear torsion bar anchor is fixed, the front pivot with the adjuster arm doesn't move, but the control arm rotates around the pivot shaft housing.  What you said does start to apply once you reach the bump stops, and you get the bounce you talked about.  Lowering does change the geometry, but so what.  That isn't really a bad thing.  It lowers your instant center and gives more and faster camber gain in rebound.  If you want to go really low, and want the car to corner better, get stiffer torsions, and cut the lower bump stops to about 3/8" thick.  For your alignment, a carpenters square against the tire will show you the camber.  1/4" in at the top of the wheel compared to the bottom of the wheel would be about 1 degree negative.  A tape measure and plumbob get the toe-in, and if you want to know caster, let me know.  It's a bit more complicated, but a tape measure and carpenter's square is all that's needed.  As my cars are now, with stock spindles, my K-frames hit the ground sometimes on rough Seattle roads.  What would happen with dropped spindles?  I'd have an extra 2" of travel, but what good is that once the K-frame's dragging the road?

 , it rides rough when you drop it down on the bump stops, but, well, duh then you have no suspention

  also with barakuda, buy some adjustable arms to give the car some caster where it should be, lower it a couple inches, next upgrade would be bigger torsion bars-

sidenote: i wouldnt be cornering hard without disks and some decent size tires

[chris70swinger]

Well, I see I have generated some debate!  I really appreciate everyone's input.

I have big plans for the Dart, late model 5.9/518 trans swap with computer, suspension and brake upgrades, mild resto.  But I recently ran a budget on all that, even low end it is $8-9K.  I can't manage anything close to that right now.

So, to get some enjoyment out of it in the meantime, my teen sons and I plan to get it on the road as kind of a rat rod, leaving the /6 auto for now.  But a rat rod needs attitude to pull it off, that's why I want it lowered. 

Looks like we'll crank the bars down a bit, trim the bump stops, and look into the adjustable control arms.  In time I suspect we'll get some dropped spindles and upgraded t-bars.  I'm cool with it scraping the ground every once in a while!

[70 Dustpan]

Here's a pic of my 67 Valiant that's lowered.

It has: tube upper arms, .920 torsion bars, 1 1/8" sway bar, modified bump stops top and bottom, and 17 wheels.

[chris70swinger]

Now, see, that '67 sits just perfect.  Not too much, just a nice stance.  How does it drive?

Are those Mustang wheels?  Does that require adaptors to get the offset right?

Looks like you lowered the rear, too- how did you do it?

[70 Dustpan]

I'm still working on it, haven't driven it yet. They're 2001 Mustang wheels with 1/2 spacers up front. Same bolt pattern. The rear has rear sliders shackles and the front mounts are flipped over to lower it. Also the springs are stock 318 non A/C springs. The rear-end is a stock length 8 3/4 out of a 65 B body.

[nd2stopfastr]

also, you can drop a bit by using a smaller diameter tire with the s6 you can figure a slightly lower max load rating could still be safe .keep in mind your bearings'll be spinning faster & might need replacing sooner than usual ( especially if you drive on the freeway alot

[MVRCorp]

You can lower the front end by the torsion bar bolt adjusters, but it makes your front tire wear unevenly and screws with your front end alignment. I had a 63 Valiant that I did this to when I was a teen and I had to replace the front tires or rotate from front to back more often then usual because of the wear pattern. also it does make the ride more stiff and when you go over a bump it will have a stiff bounce to it. heres a pic of it behind my little sis, those are the stock 13" rims on it I had 14" crager ss rims but had to throw the stockers back on them because of tire wear. By the way it was so low to the ground once I got one of those fix it tickets because the K-frame was lower than the bottom of the rim. Adjusted the bolts back up......... took the ticket down to the court house and had it signed off because it was above the bottom of the rim.............. latter turned them back down............. gave it that racked hotrod look but only had a /6 and 904.

Hey, little girl.......want a cookie?   

[thecarfarmer]

Man, I can't believe how many people complain about a firm ride.

I've had a few cars that I put 'on the snubbers'; didn't seem that rough to me.

At a bare 'hokey-ass' minimum, I'd suggest at least taking a tape measure and adjusting the toe afterwards...

-bill

[68383valiant]

Hey your bolt circle is 4" not 4 1/4 !

[moparteacher]

Here's a couple of things to keep in mind.

A greater forward rake from lowering the front more than the back moves the upper ball joint forward in relation to the lower ball joint.

This creates less positive caster or possibly negative caster.

Less positive caster diminishes steering returnablity possibly to the point that the steering wheel will pull into the turn. This can make cornering unpredictable. Less positive caster also diminishes directional stability and may cause the vehicle to wander. Although less positive caster will give a smoother ride as long as you stay off the bump stops.

The forward rake will change the rear thrust during cornering. It will reduce the inward thrust of the rear tires resulting in understeer.
Flipping the forward mount of the rear springs has the opposite effect and will result in oversteer. Either way, predictable cornering is diminished.


Good luck

[Jim_Lusk]

The torsion bar adjuster bolt really does NOT adjust the t-bar, but moves the LCA away from the LCA pivot arm. This is true as long as you weren't sitting on the LCA bumpers. If you go low you really need stiffer t-bars to keep hitting the LCA bumpers on the frame at every bump.

[signet]

you can always channel it 4".

lots of work but low dollars and no geometry changes.

[chris70swinger]

I had not checked in for a week or more, just now checking the latest responses.  I now have more dumb questions...

First one is, in what way do adjustable UCA's adjust- do they somehow lower the car by themselves, or do they only allow you to get back to proper alignment once you lower it by adjusting the t-bars?  I have never seen on here exactly how you adjust the t-bars, but I admit I haven't got under there and studied it yet.  I just got the car home from storage last week...

I do plan on a slight rake, but I will be lowering the rear a bit as well.  I would love it to look like 70Dustpan's Valiant, as pictured above.  I don't think that will throw the caster off bad enough to affect the handling dramatically.

I'm OK with a firm ride.  This ain't a Cadillac, or a Ferrari.  If I want to carve corners, I got another car for that...

[Jim_Lusk]

Adjusting the ride height (the correct term, because you really aren't doing anything to the torsion bars until you go too far) is as simple as turning the large bolt in the center of the lower control arm. Adjustable upper control arms allow you to set the alignment when you have gone too low for alignment with factory upper arms.