abodyjoe
Well-Known Member
Let me see if he has any pics of them. If he does ill post them for ya.
Hotchkiss Leafs Installed
- Thread starter GMachineDartGT
- Start date
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Let me see if he has any pics of them. If he does ill post them for ya.
abodyjoe
Well-Known Member
here ya go pete. remember these are home built. they are on a 340 not a 408. he still has the car and they are still on it...
jrlegacy23
68 Barracuda
I like the stance. I wouldn't even put lowered spindles on. Nice job.
O sorry. Was referring to my tires in the front, I'm having to bend the fenders a little bit to get them to clear correctly. Not a very good picture but this is what mine looks like at the moment.
roadrunnerh
Well-Known Member
The car sits a little low, but that's just my opinion.
I prefer a little rear to front rake.
I prefer a little rear to front rake.
GMachineDartGT
Senior Member
The dropped spindles are necessary for two reasons.
At the current height there is not enough clearance at the lower bump stops even though I use 11/16 urethane pieces. The second reason is due to the drop in the current suspension, the roll center is below ground. The front roll center should be above ground in the 5" range. Once the spindles are installed, I get the crank up the t bars to put the height back to where it is now. This will correct these issues properly and should make a dramatic difference.
Once the spindles are installed, I will play with the heights to get an optimal 1.5 degree rake. At this point, I am thinking I may have to raise the rear slightly, but I want to measure the anti squat angle first. I will include pictures of my process.
At the current height there is not enough clearance at the lower bump stops even though I use 11/16 urethane pieces. The second reason is due to the drop in the current suspension, the roll center is below ground. The front roll center should be above ground in the 5" range. Once the spindles are installed, I get the crank up the t bars to put the height back to where it is now. This will correct these issues properly and should make a dramatic difference.
Once the spindles are installed, I will play with the heights to get an optimal 1.5 degree rake. At this point, I am thinking I may have to raise the rear slightly, but I want to measure the anti squat angle first. I will include pictures of my process.
jrlegacy23
68 Barracuda
That makes sense, I was not thinking about the suspension in that aspect.
GMachineDartGT
Senior Member
I spoke to Schumacher about his tri ys which he said he makes. However, he did not change the pitman clearance, so I'm not sure what he was after when he designed them.
Joe, the pics are coming up red x's.
Joe, the pics are coming up red x's.
Keep in mind a couple of things with the drop spindles-
First, you're not changing the spring rate of the torsion bar by changing the torsion bar adjusters. The spring rate is fixed, and does not change. You're really not even changing the preload, the torsion bar adjusting bolts just change the angle of the lower control arms with respect to the torsion bar/pivot.
Second, you will be worsening your bump steer. By moving the spindle up with relation to the steering arms, you'll end up with more angle on the steering arms. Now, I run drop spindles on my Challenger, and did not actually notice the increase in bump steer. But, numerically anyway, it got worse.
And finally, watch out for the tie rod ends with your rims. The nice thing about using the stock suspension set up with larger rims (17" and 18") is that the tie rod end will actually fit inside the rim instead of interfering with the lip, so you can run more backspace. The drop spindle basically turns a 17" rim into a 15" rim with respect to the tie rod clearance, so backspace becomes an issue again. With 18's it'll probably still be fine, but it may depend on the rim.
GMachineDartGT
Senior Member
I am not sure how bump steer changes when the only thing that is moved is the spindle. The location of the lower bj/steering arm does not change.
18 x 8", 5.42 backspace is not an issue with clearance.
In order to raise the car with the t bar adjusters the bar has to have preload or else how would the car be raised? And in some cases why can you back off the adjusters and the suspension still has ride height? The torsion bar adjusters add or subtract preload to gain/lose ride height.
18 x 8", 5.42 backspace is not an issue with clearance.
In order to raise the car with the t bar adjusters the bar has to have preload or else how would the car be raised? And in some cases why can you back off the adjusters and the suspension still has ride height? The torsion bar adjusters add or subtract preload to gain/lose ride height.
72BBSwinger
Well-Known Member
Yes getting more height does take more preload, but that isnt preload like you think. The weight of the car and the rate of the tbar wont change. What WILL change is you will get into the higher range of the bar when you compress and use your new found gain in up travel. That is where you will see more "rate". The bump steer thing with the spindles I dont buy, since the only thing changed is the center of the hub. Control arm angles and tierod angles arent effected.
joes68340s
Well-Known Member
Nice car. GMachine, Im curious. Whos offset spring bracket are you using. If mopar did you remove the welded nut and redrill and weld new nut. Buy raising the eye location did you also have to enlarge hole in frame since this raises the attachment bolt higher on the bracket. Thanks
The tie rod angles DO change. The control arm mounts stay in the same place, but, the hub moves 2" up and away from them. Which means that when everything is sitting on the ground, you have in effect lowered the control arm mounts by 2" (since the height of the wheel doesn't change). The steering arms will end up with more angle. I can take pictures of my steering arms if you don't believe me, but it does change the angle pretty significantly. Better yet though, I'll post a link up to another thread where a member actually ran my suspension geometry through a suspension program, and compared it to a stock suspended car...
see these graphs here...
It's a pretty long thread and discussion, but you can see from the graphs (produced using my suspension geometry measurements) that the bump steer was increased with the drop spindles. The first few graphs are the stock suspended car (lowered a bunch), the second set are based on my car (72b&b).
The torsion bar adjusters don't really add or subtract preload. They don't actually twist the bars. If you take a look at the lower control arms, you can see that what actually happens is the adjuster changes the angle of the lower control arm with relation to the torsion bar anchor in the LCA. This is no different than clocking the LCA's. It changes the amount of available suspension travel, but has no effect on spring rate.Torsion bars are straight springs. Unlike a progressive spring, the spring rate of the torsion bar is fixed, and constant. For example, if you have 150 lb/in torsion bars, that's always what they'll be. 150 lbs of force per inch of deflection. Now, if you're using more of that travel, then you will see higher suspension loads. But the spring rate didn't change. And of course, your handling and ride will improve greatly if you're not bottoming out your suspension all the time.
abodyjoe
Well-Known Member
ahhh crap.. hold on i'll fix it..
abodyjoe
Well-Known Member
see if this works....
here is his answer when i asked how he thinks they flow..
here is his answer when i asked how he thinks they flow..
autoxcuda
Well-Known Member
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Those are Dbdartman's with the 68 Dart post car, IIRC ???
He's from New Jersey also??
abodyjoe
Well-Known Member
California Dart
Dont List Websites Here
I just put the Hotchkis springs on my 74 Dart and it lowered my car 3 inches in the rear. I had to put the stock mounts back on and it was still 1' lower than stock but rides very nice with my Bilsteins.
autoxcuda
Well-Known Member
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Did you have original 1974 leaf spring on your Dart before?
GMachineDartGT
Senior Member
I agree the torsion bar is not progressive, so I am not assuming the rate will change. However, once lowered the t bar is completely unloaded, kind of like a coil spring that would be completely unloaded at ride height - not a good thing.
Another thing is the bumpsteer on E bodies is MUCH greater than with A bodies. I have not checked mine yet, but, the tests Bill Reilly did many years ago showed the bump steer through the entire range and it was pretty minimal.
The third thing here is the roll center is raised, but when the roll center is below ground with the current setup, its what you want. This is why the car feels better. Put all the proper angles together with good tires and alignment, and you have something that works well.
Another thing is the bumpsteer on E bodies is MUCH greater than with A bodies. I have not checked mine yet, but, the tests Bill Reilly did many years ago showed the bump steer through the entire range and it was pretty minimal.
The third thing here is the roll center is raised, but when the roll center is below ground with the current setup, its what you want. This is why the car feels better. Put all the proper angles together with good tires and alignment, and you have something that works well.
mopardude318
Well-Known Member
OOh God! Those would be perfect for my 318 Build!!! How much would those suckers cost? I'm bettin close to a grand, maybe more? I do know custom headers are expensive..lol
72BBSwinger
Well-Known Member
I see what you are saying. Basically with the drop spindles you raised your suspension and gave your tierod more angle. So you had bumpsteer with your car at stock height with stock spindles then? Drop spindles don't change your attaching points.
rjh233
New Member
Does anyone know the spring rates for the Hotchkiss leafs?? And how do the compare to de-arched SS springs?
bjkadron
Well-Known Member
Looks good! Have you figured out what the antisquat is yet? Also, what springs were you running before?
Yes, as GT pointed out my Challenger has a bigger stock bump steer issue than A bodies do, by virtue of the e-body suspension being used as the same platform for all the station wagons. They ended up with more anti-dive etc built into the design to handle the MUCH heavier station wagons.
The frame attachement points don't change with the drop spindles. But, because you move the "axle" on the spindle upright, you increase the distance between the "axle" and the outer steering arm attachment. This in effect lowers the outer steering arm attachement, as the wheels are the same. So, with the drop spindles the upper and lower control arms take on a more stock appearing angle, much closer to design than a severely lowered stock suspended car, raising the roll centers etc. But the tie rods end up with more angle.
You can see it in the computer model here, the thing that you have to keep in mind is that because the wheels aren't located in the same place on the spindle, both of these models end up with similar ride heights, even though it looks like my car has been raised. I added in the orange lines to show the axis point of the wheels. Its not to scale, but it gives a little more perspective on what you're looking at. The magenta looking lines below the LCA are in fact the steering arms.
You can also compare the stock spindle (top) to the drop spindle (bottom). Since the wheel is still the same height, and has to sit on the ground, you basically lower the outer steering arm attachment point by 2".
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