Front subframe sitting on bump stop ?

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GREEN GHOST

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Is the feont subframe supposed to actually contact & sit on the bump stop? Do I have to crank the torsion bars to lift it off ? Thanks
20220411_210717~2.jpg
 
That picture is taken from behind the front tire looking forward
 
Yes some folks like to lower their cars and they think dropping them on to the bump stops is the way to go ...truth is it's just hard on the suspension has no more travel on the bushings take the brunt.

Crank up the lower control arm Adjusters
 
Lift the body and put it on jack stands so the front suspension has little to no weight on it, THEN make an adjustment.

My 67 dart has about 1 inch of travel to the peak of the bump stop, (old age)

The FSM has dimensions to measure for "factory correct" ride height.
 
Yes some folks like to lower their cars and they think dropping them on to the bump stops is the way to go ...truth is it's just hard on the suspension has no more travel on the bushings take the brunt.
Crank up the lower control arm Adjusters
Figured it was hard on suspension. Would I crank torsion bars or lower control arms to raise it?
 
Lift the body and put it on jack stands so the front suspension has little to no weight on it, THEN make an adjustment.

My 67 dart has about 1 inch of travel to the peak of the bump stop, (old age)

The FSM has dimensions to measure for "factory correct" ride height.
Good pointer & reference. Thanks
 
This is how it sits now. I like the stance & don't mind the ride. Just don't want to beat the crap out of the front end and have to do something to aid in traction. It doesn't hook & the front passenger side lifts
20220402_091248.jpg
20220326_093011.jpg
 
If you like the lower look you can replace the bump stop with a thin one. No need for a jacked up up front end if your suspension will support it.
 
That's way too low man. You're gonna take that oil pan slam out.
 
If you like the lower look you can replace the bump stop with a thin one. No need for a jacked up up front end if your suspension will support it.
That might be the ticket. I'm going to look for them
 
Definitely makes you very aware of the road
I'm sure. The bump stop hitting the frame there also makes the control arm act like a lever trying to pull the lower control arm bushing out. It cannot of course, but it will ruin the bushings.
 
If you have the stock torsion bars, you really need to raise the ride height until you have about a 1” gap between the top of that bump stop and the frame.

If you leave the car where it’s at with the stock torsion bars and cut the bump stop down, you will HAMMER the suspension on the frame all the time because the stock torsion bars don’t have enough wheel rate to control the suspension with that little travel.

If you want to keep that ride height, you have two options. The better way to do it is install larger diameter torsion bars. The higher wheel rate means you’ll use less suspension travel, so, you can trade that for ride height. With larger torsion bars you can reduce the height of the bump stop, as long as you’re not hitting the bump stop very often. Fair warning, it looks like your LCA’s are about parallel to the ground. That’s actually great for suspension geometry and handling. But you’ll need 1.12” bars or close to them to maintain that ride height even with a short bump stop. That’s what I run on my Duster, and in my opinion I’m as low as I can go. I don’t hit the bump stops all the time, but it does happen often enough that lower is a bad idea.

The other way would be drop spindles. If you want to keep smaller diameter torsion bars, like if you’re mostly drag racing, that’s what you’ll need. But drop spindles add bump steer and mess with the roll center. So, for looks or going in a straight line they’re ok, but you can toss the handling capabilities right out the window as the suspension geometry suffers.
 
I'm sure. The bump stop hitting the frame there also makes the control arm act like a lever trying to pull the lower control arm bushing out. It cannot of course, but it will ruin the bushings.
That's what I was afraid of
 
If you have the stock torsion bars, you really need to raise the ride height until you have about a 1” gap between the top of that bump stop and the frame.

If you leave the car where it’s at with the stock torsion bars and cut the bump stop down, you will HAMMER the suspension on the frame all the time because the stock torsion bars don’t have enough wheel rate to control the suspension with that little travel.

If you want to keep that ride height, you have two options. The better way to do it is install larger diameter torsion bars. The higher wheel rate means you’ll use less suspension travel, so, you can trade that for ride height. With larger torsion bars you can reduce the height of the bump stop, as long as you’re not hitting the bump stop very often. Fair warning, it looks like your LCA’s are about parallel to the ground. That’s actually great for suspension geometry and handling. But you’ll need 1.12” bars or close to them to maintain that ride height even with a short bump stop. That’s what I run on my Duster, and in my opinion I’m as low as I can go. I don’t hit the bump stops all the time, but it does happen often enough that lower is a bad idea.

The other way would be drop spindles. If you want to keep smaller diameter torsion bars, like if you’re mostly drag racing, that’s what you’ll need. But drop spindles add bump steer and mess with the roll center. So, for looks or going in a straight line they’re ok, but you can toss the handling capabilities right out the window as the suspension geometry suffers.
Thanks all the info& such a detailed response. I have to figure out what size bars I have now but Ifv anything I'd want the thinnest best possible for two reasons. #1 I want to pair a thin bar with 90/10s for drag racing. #2 depending upon how I turn the wheel the driver bar will vibrate against the header tubes and rattle like crazy. I also do like the stance of the car now
 
Thanks all the info& such a detailed response. I have to figure out what size bars I have now but Ifv anything I'd want the thinnest best possible for two reasons. #1 I want to pair a thin bar with 90/10s for drag racing. #2 depending upon how I turn the wheel the driver bar will vibrate against the header tubes and rattle like crazy. I also do like the stance of the car now
Just something to think on. Why not get the car high enough in the front to protect the oil pan, then raise the rear to get the same rake you have now? I know it would be raising the whole car, but the stance would essentially be unchanged and the front suspension correct and also keep the oil pan safe. I mean, do you want cool looking, or a big puddle of oil on the ground?
 
Thanks all the info& such a detailed response. I have to figure out what size bars I have now but Ifv anything I'd want the thinnest best possible for two reasons. #1 I want to pair a thin bar with 90/10s for drag racing. #2 depending upon how I turn the wheel the driver bar will vibrate against the header tubes and rattle like crazy. I also do like the stance of the car now

If that’s the case, you probably want to go the drop spindles route. I’m generally not a fan of them but I build my cars for autoX and handling, and doing that means larger bars anyway so the drop spindles become unnecessary to lower the car. You can correct the added bump steer other ways.

If turning the wheel actually causes the headers to rattle against the torsion bar, you may also want to look at your engine mounts, steering box and K frame. Because turning the wheels shouldn’t change anything as far as header to torsion bar clearance unless something is moving that isn’t supposed to move when your turn the wheels.
 
Figured it was hard on suspension. Would I crank torsion bars or lower control arms to raise it?
The t bar adjuster is in the lower arm. Clockwise looking up at them, turn them in till it's where you want it.. then have it realigned. If you wanna play with unloading it.. raise it to the height you want.l with a jack..and with a stand as a back up ..youll reach under and more easily torque them up... and right when it becomes a little harder to turn is where the raised height is. Stop and lower to dbl check. I'd just do it on the ground though..IF you can still reach under.
 
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I just cut down the stops on my race car. AutoZone has new ones and they are cheap.
They adjust the bars and you can keep the ride height that you like. Check adjustment
every month or two. Support the car so no weight on adjusters. I stripped one back in the 60s
and dropped it on my chest.
 
Just something to think on. Why not get the car high enough in the front to protect the oil pan, then raise the rear to get the same rake you have now? I know it would be raising the whole car, but the stance would essentially be unchanged and the front suspension correct and also keep the oil pan safe. I mean, do you want cool looking, or a big puddle of oil on the ground?
Cool looking, hooks well in straight line, & oil pan safety. . .. .my main concern with the oil pan is not so much just driving around but when the thing hooks and lifts if it will smack when coming down
 
If that’s the case, you probably want to go the drop spindles route. I’m generally not a fan of them but I build my cars for autoX and handling, and doing that means larger bars anyway so the drop spindles become unnecessary to lower the car. You can correct the added bump steer other ways.

If turning the wheel actually causes the headers to rattle against the torsion bar, you may also want to look at your engine mounts, steering box and K frame. Because turning the wheels shouldn’t change anything as far as header to torsion bar clearance unless something is moving that isn’t supposed to move when your turn the wheels.
I'm kinda thinking it has something to do with the steering rod / box. I do have a good amount of play in the steering wheel. . The clearance between the header and steering rod is literally paper thin.
 
Besides using a micrometer foes anyone know hoe to identify the torsion bars? Any markings or numbers to look for on the bar?
 
Besides using a micrometer foes anyone know hoe to identify the torsion bars? Any markings or numbers to look for on the bar?
On the end of the bar, where the clip is, there may be some grime & grease in the way. Each bar will have a 3 diget number. Right side even Left side odd IIRC.
 
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