Fox T-Bird/Cougar Forums

Technical => Suspension/Steering => Topic started by: jcassity on March 30, 2009, 03:19:16 AM

Title: serious discussion on handling
Post by: jcassity on March 30, 2009, 03:19:16 AM
I am wanting to discuss curves with our cars and stock parts.

anyone ever brainstorm an idea that would assist in preventing our cars from leaning while in a curve?  This greatly reduces control as you all know.  Sure you can swap out all of this and that and stiffen the ride but what if, just what if there was a way either electrically or mechanically we could devise a system that prevents the struts from reactiing to curves only.  Such a device tied into to a steering column position sensor and perhaps coupled with a speed sensor input would be the two factors that trigger the system to enguage.

As an example,, imagine your in a tight right hand curve.
your speed is over 30mphyou have a device mounted at the top of your strut tube with two brake pad like things that would clamp around the strut cylinder when you your steering wheel is at X position and your speed is at Y+ mph.
the driver strut would not compress / compress less because a brake pad system has stopped it from doing so.  I
I imagine two sterring column position sensors or simple contacts / slip rings to keep things far more simple.  One for each side of the car.

This is just an idea i came up with as most of the time i try to think of things that are applicable on most any venu in the catagory I design around.
I am only doing pipe dreams now but the white coug is getting closer and closer to making its way into the garage.
Title: serious discussion on handling
Post by: massCougarxr7 on March 30, 2009, 10:57:36 AM
sounds like a plan, well more like an idea,,..... ive also thought about making my own coil overs that are non....adjustable,.....
too bad you couldnt put a valve on the strut, with an airline, and instead of your brakes clamping on the strut, it would fill with x amount of psi........(front and back...)
Title: serious discussion on handling
Post by: Thunder Chicken on March 30, 2009, 01:59:49 PM
There already is just such a system, Scott, and you'll find it stock on all 87-88 Turbo Coupes. It's called Programmed Ride Control :D It doesn't have a "brake" as you suggested, but instead it has a motor moving a device that changes the valving in the strut - smaller orifice increases strut stiffness, larger orifice decreases strut stiffness. When the steering wheel position sensor signals the PRC system that you're going into a turn it stiffens up the outside strut/shock compression and the inside rebound (makes outside struts harder to compress, inside ones harder to pull apart) in order to reduce body roll.

Newer cars go a step further and actually change the viscosity of the shock fluid instead of changing the size of the openings it goes through. That's the electronic suspension found in new Caddies and Corvettes.
Title: serious discussion on handling
Post by: ~AC on March 31, 2009, 12:26:47 AM
I hear the idea about something that could be done to the strut.  One thing that i've seen, and considered for the MX5 is a air bag system.  no not the one in a dash or air ride.  those crazy puppiesanese like to put their HEAVY 4 door cars (the same size as our tbird-cougars if not bigger) all the way on the ground with adjustable coilovers. but when your running a 4500 dollar front bumper and cant clear the small bump pulling into a store or even your own drive way.. do you adjust the coilovers as you come accross such a hurdle?  well, they made a system that goes between the top mount of the coilover and the coilover itself.  it's made to raise the car on FIXED coilover applications about 2 inches.  this is just like an air ride system, as in you use switches to give your car the lift.

now if you could come up with something similar to fit between the strut tower and the strut, you could basically lean a car INTO a corner, and on a soft suspension possibly it wouldnt lean into a corner, but stiffen that corner of the car a bit.

how would this be controlled?  well i dont suppose you could mount 2-4 switches on your steering wheel and adjust them on the fly.  so why not use a G-ball type of device that would react to the forward, braking, left and right G forces changing the ride height and the strut stiffness for you as needed.  getting this programming right would be key and very sketchy if it went wrong or a bag blew mid-corner.

youre basically trying to stop or slow the compression of the strut, so why not counter act the problem with an airbag?  you COULD use hydrolics but then you might develop a oil leak in the driveway...

just adding to the idea. :burnout:
Title: serious discussion on handling
Post by: t3skidoo on March 31, 2009, 12:50:31 AM
Ever heard of Citroen (http://"http://en.wikipedia.org/wiki/Citro%C3%ABn_SM")?  Or Lotus (http://"http://www.f1fanatic.co.uk/2007/05/17/banned-active-suspension/")?
Title: serious discussion on handling
Post by: ~AC on March 31, 2009, 01:18:08 AM
those systems are engineering marvels, thus cost is astronomical and probably out of the realm of even a functioning prototype.  Lotus focused on self leveling to the point they wanted lasers or radar to read a road to be active.  citroen went the same way but used nitrogen gas to replace the steel spring.  im thinking of what could i do to help something that already exists, like an 80's thunderbird/cougar.

good read though :)
Title: serious discussion on handling
Post by: jcassity on March 31, 2009, 01:50:25 AM
Thunderchicken pointed out an obvious error to my thread.

There are stock parts that do this and I had that in the back of my mind the whole time I wrote this up. Obviously I know the ride control system is out there.

I was speaking on behalf of the other stock struts without ride control.  something of a simple design.

This is probably a really dumb thread,, Phale of a thread to be honest.
Title: serious discussion on handling
Post by: t3skidoo on March 31, 2009, 05:24:39 PM
Quote from: jcassity;265002


This is probably a really dumb thread,, Phale of a thread to be honest.


I disagree. 

My post wasn't meant to be snarky, but to point out that there might be a system that you could pirate instead of starting from scratch.  Obviously a Lotus F1 active suspension isn't going to be easy to find, but just about any modern Citroen has elements of what you're describing. 

When I first put Konis on the old bird, I thought about pen 15pit adjustments for the struts using an electric motor controlled mounted under the hood.  Koni shock design prevented the same idea for the rears, but Tokicos used to be externally adjustable.

Some Euro Fords have electric PS pumps that use a 3D index to control the pump motor speed, using vehicle speed and steering angle.  Something similar might be used to control solenoids or electric motors attached to externally adjustable struts/shocks.

And of course, there's the factory Ford solution, PRC.  My question is, are those parts available in the aftermarket?
Title: serious discussion on handling
Post by: jcassity on March 31, 2009, 11:27:46 PM
if i thought it was snarky,, i would've said something:D

not sure what your sweating,,, certainly dont worry bout my feelings cause im not that sensitive.:evilgrin:

I was just pointing out that i think im guilty of wasting internet space the more i think about it., thats all.  It felt good at the time, now I think its a waste of thought, time, when simple manual adjustable shocks (although not automatic) suit and supply the need.
Title: serious discussion on handling
Post by: The Hawk on April 01, 2009, 11:35:01 AM
Quote from: jcassity;264749

you have a device mounted at the top of your strut tube with two brake pad like things that would clamp around the strut cylinder when you your steering wheel is at X position and your speed is at Y+ mph.
the driver strut would not compress / compress less because a brake pad system has stopped it from doing so.



That's a recipe to crash.

You can't control body roll by stopping a strut from compressing......it has to be able to move up and down to conform to the road. If the strut was prevented from it's normal cycle in the middle of a corner and you hit even a small dip it will cause the car to lose grip as there is not enough "give" in the tire to absorb a sharp dip a corner.....the car will skip and then begin to understeer.

 This phenom is one of the reasons people with Mustangs who are into the road race thing ditch the factory rubber bump stops on the front struts and replace them with units such as the ones from Koni which are way more compressible. I've personally been in and witnessed many a Mustang skip right off a race track in a corner when it hit the bump stops.
Title: serious discussion on handling
Post by: Thunder Chicken on April 01, 2009, 02:35:00 PM
Scott: There's nothing wrong with trying to solve problems, nor is there anything wrong with trying to come up with a new solution to a problem somebody else has already solved. In the end, though, you've just got to look at your solution, compare it to other solutions, and honestly ask yourself which is the better one. I actually really enjoy posts like this because they make a person think. I may come across as a pessimist because I tend to think more in the vein of "why it won't work", but thinking potential problems out is the first step toward overcoming them.

In the case of the brakes-on-a-strut thing, in addition to the problem Hawk pointed out, I can see other problems (there's that pessimism). Say you applied the brakes only to stiffen the strut, not to stop its movement altogether: This would eliminate the problem Hawk pointed out, but it would create new problems. First, brakes on a strut rod are going to wear the strut rod, and the strut seal depends on that rod being a certain size and shape. Then there's the heat issue. Rubbing brake pads on a strut is going to generate a lot of heat. This heat is going to weaken the rod, and is also going to distort it, adding to the wear problem mentioned above (while also affecting alignment angles). The heat would also travel down the strut rod and burn up the seals as well as heat up the oil in the strut.

You could design a strut or shock that solves some of these problems, perhaps by building a friction surface and heat sink into the design, but there's where that "somebody else already solved it" thing comes in. And it's not like friction shocks haven't been tried. Many very old cars used them, and by "old", I mean "1930's and older". Come to think of it, I think the Morgan still uses them.

There is another way, besides struts/shocks and sway bars, to limit body roll. You could change spring rate on-the-fly: Stiffen up the outside pair in a turn to hold the body level. This, too, has been done with compressed air and air springs. The Lincoln Mark VII and VIII were examples.

One last thought: ANY type of on-the-fly suspension adjustments would have to be controlled by computer. It would simply not be possible to manually adjust these things fast enough. By the time you processed the required action in your mind and actually started performing that action it's already time for another reaction, and your input, coming at the wrong time, will likely do more harm than good. Meanwhile you're trying to drive the car, too...
Title: serious discussion on handling
Post by: Kitz Kat on April 01, 2009, 04:50:09 PM
Hey scott, try this , why can't we get all the the fat burning gyms with the pedal powers make juice. It may not be free for them but?
Title: serious discussion on handling
Post by: softtouch on April 01, 2009, 06:13:23 PM
Quote from: Kitz Kat;265306
Hey scott, try this , why can't we get all the the fat burning gyms with the pedal powers make juice. It may not be free for them but?


Somebody translate please.
Title: serious discussion on handling
Post by: 86XR7project on April 01, 2009, 06:16:47 PM
Quote from: Kitz Kat;265306
Hey scott, try this , why can't we get all the the fat burning gyms with the pedal powers make juice. It may not be free for them but?


Been drinking today I see......
Title: serious discussion on handling
Post by: Kitz Kat on April 01, 2009, 08:22:43 PM
Only Scott would comprehend. Maybe!
Title: serious discussion on handling
Post by: jcassity on April 01, 2009, 08:46:45 PM
Quote from: Kitz Kat;265306
Hey scott, try this , why can't we get all the the fat burning gyms with the pedal powers make juice. It may not be free for them but?


now thats entertainment:rollin:  There's so much unsaid above that it leaves room for the imagination to insert what you might have meant:D
Title: serious discussion on handling
Post by: jcassity on April 01, 2009, 08:56:01 PM
nice point on the nose of a car skipping like that ,,, never thought about it that way.
Title: serious discussion on handling
Post by: CootersXR7 on April 02, 2009, 09:45:33 AM
I read several years ago about a Torque Multiplying Sway Bar. Some of the new Jeeps and the Power Wagon have an electronic center disconnect (from American Axle), and I think there was mention somewhere of an addendum to this technology that would allow torque multiplication to the loaded side. There are patents (and applications in existence) for Torque Multiplying Sway Bars. I have never heard of anyone using one on a Mustang or Bird, but why not? I found this Austrailian link to a system of similar idea, but waaayyyyy more complex than the one I read about several years ago: http://autospeed.com/A_0477/cms/article.html (May not even be worth looking at)

Perhaps this is the one I read about, although I thought it was American Axle, and I remembered it being more mechanical:
http://delphi.com/manufacturers/auto/other/ride/active/ (http://"http://delphi.com/manufacturers/auto/other/ride/active/")
Title: serious discussion on handling
Post by: EricCoolCats on April 02, 2009, 10:15:23 AM
Quote
Newer cars go a step further and actually change the viscosity of the shock fluid instead of changing the size of the openings it goes through. That's the electronic suspension found in new Caddies and Corvettes.

When I first saw a demonstration of this on TV a few years ago, I had to pick my jaw up from the floor. The fluid has a magnetic suspension that rearranges its molecules (stiffens) when an electrical current is added. Otherwise it is just like a normal shock; instead of being filled with gas it's filled with this fluid. The fluid was like $2000/gallon or something ridiculous, at least at that time.

But one of the first things that went through my mind was, "Wow, this will make a great replacement for the PRC shocks in the Turbo Coupes." Think about it: all of the necessary hardware is already in place (steering sensor, actuator wiring, ride control computer, etc.). So my thinking was, remove the PRC actuators, clip in a new harness from the old PRC actuators to the shocks, and JUST maybe that might work. The same signal that the ride control computer would send to turn the actuator would instead stiffen the shock. It's the same principle, just different methods of delivery. The firm/auto button should also theoretically work.

And if a generic Fox body retrofit kit were to be made, then everyone could enjoy the same benefits as a Turbo Coupe. Might be a little tougher, and obviously more sensors and whatnot would need to be installed, but there's enough room to do anything necessary.

Just food for thought. :)
Title: it's almost time to remove the alternator
Post by: t3skidoo on April 03, 2009, 12:30:13 PM
http://arstechnica.com/science/news/2009/02/fuel-boost-from-road-bumps.ars