TORSION BAR LOWERING
 

I want to lower my 68 Fury.
I know how this is done but want to order some appropriate lowering blocks for the back to go with it. Problem is I don't know how much I can wind the torsion bars down and I can't just do it because the car is in pieces and up on stands being painted.
As I'm in England I don't want to wait ages doing nothing to the car while parts turn up.
Anybody know what the maximum drop I am likely to be able to achieve is.....????????

best way to tell is to check how much clearance you have at the wheel wells when the suspension is at its lowest height and then drop it a little less then that, or at least thats how ive always done it

raindance, I think that mancinis, offers a spring perch kit, where the pads that are welded onto the axle tubes for the springs, are a lot thicker, so the whole rear sits higher into the wheel wells. you cut the old 1`s off and weld theese new 1`s in its place.

A lot of it depends on how low you want it to go. You can notch the frame and body and go real low or you can just keep it simple with cranking the torsion bars and installing some 1"-1.5" blocks.

Thanks guys. I have a pretty good idea of how to do the job but wanted to know how low I can go just by cranking the torsion bar adjustment.
I don't want to get into notching the frame or body as I'd like to keep this car fairly stock.
Normally, I'd just skip on down to the workshop and get cranking. Problem is I can't at the moment as the car is in pieces and is being painted. I want to get some parts on their way from someone like Summit or Jegs while I'm still painting the Plymouth. This way I don't have to wait ages for the lowering blocks to clear UK customs and can push on with the lowering right after the paint is done.

So, is 1 1/2 inches the max I can crank the torsion bars ............????

Terry.

Just get someone the size of my Mother-in Law to sit on the front end and simulate the engine weight. :eek:

Just kidding, I love my Mother-in law...and for $50 bucks you can too. :eek:

:rolleyes: Sorry for the bad jokes.

^^^ i thought that was funny :D

Thanks for the replies and the bad jokes guys.
I'd need about 4 of my mother in laws. I think I'll spend the fifty on a lowering block kit....................

The difference between in-laws and outlaws is that outlaws are WANTED!:D

Amen :D

Thanks for your answers, guys.
I'll read and inwardly digest........................

Just to update this post and for future reference of others:

I put my Plymouth back on the floor today and have lowered the front by cranking on the torsion bars. I've dropped her by 2 inches and no obvious problems. Maximum feasable drop achievable just by cranking seems to be about 2 1/2 to 3 inches before you run into other issues.

Terry.

The lower you take it with the torsion bars, the bouncier it's going to get since the resistance of the bars is reduced. You may want to consider getting some really heavy front torsion bars if you're going to take it down as much as you can.

I hope that you replaced the rest of the front end as well. dont forget, the abuse that your putting the upper and lower joints through, and the lower control arms.

Thanks gents.
I can see that radical drops in any suspention will alter geometry and therefore possibly exert different forces on its components but I need to ask why
changing the spring rates (in this case heavier torsion bars) is necessary in this case. Is there really that much preload on the torsion bars???

As far as I can make out, all that's happening is that you're changing the angle of the lower arm to the torsion bar while the car is at rest on the wheels by about ten to twelve degrees in my case. I can see that with very large angle changes the result would be that the lower arm would have slightly increased leverage on the torsion bar since track (and therefore leverage) increases as the lower arm reaches its horizontal position.
BUT can someone explain why in this case where the angle change is minimal why this would appear to have such a huge affect on the suspension and its components. It's not really outside of its normal envelope of designed travel after all.

I'm not trying to be funny here guys, or to question greater wisdom than mine but I feel it's important to fully understand this system and any implications it has BEFORE I drive the car on public roads.
Terry.

Correct, it is not outside the range of travel. However the components are designed to maintain a certain degree of chamber at a certain ride height. The pupose of this is for handling. Lets say that on a left turn the right front suspension compresses. The suspension is set up to increase the positive chamber of the right wheel as the body rolls, and to counter the effect called "tuck-under" where the inertia of the vehicle would appear to be trying to peel the tire from the rim. You want the chamber to change to maintain as much of a perpendicular angle to the road as you can to maximise the tires contact patch. On the other side of the car, the left wheel has the weight unloaded from it, the design allows the extended suspension to apply negative chamber to the wheel to try to keep it more perpendicular to the road and maintain maximum contact area. Clear as mud, eh? On some suspensions this can be compensated somewhat by adding shims to the upper control arms to push the top of the tires out while at rest. However the geometry is still affected because on a hard corner the supension has very little travel. Once the travel is used up, the knetic energy will look for another place to exert itself, usually understeer. The wheels will be turned, but the car will still want to plow straight. All in all, if you can drive sanely, and dont care about twisty roads, then I suppose you could get away with stiffer spring rate and control arm adjustments if your car has the adjustability available. Regarding spring rates, a stock spring would deflect say 2" on a small bump. Well that would put you into you bump stop every time and loosen whatever fillings you have. A stiffer one would minimize that to say 1". Still not a pleasant ride as that energy must go somewhere. Hope I helped some, Scotty

Thanks Scotty. Got it now.

I'll make some allowances and compensations for this.