No ones taken my bait yet!
I think it's been built. I think most here have looked at it or seen it.

Ralphy

Last edited by Ralphy (9/30/2012 5:04 pm)

Damn!
Phantomjock is the winner. I'm a little stupid and slow. However I spent some time the other day trying to dissect the KA T5 design. Seems I spent too much time thinking the lower trailing link was the primary link/area. The upper rear is where the real action is. Looking at this link closer I noticed it's much closer to the half shaft meaning a higher amount of acceleration/braking forces go through it. Second, being further to the rear means it takes less effort to affect the chassis height/jacking. Then third scaling the home page pic. I can guess it's only 75% of the length of the lower forward link which means it can gain more angle per inch of travel. The upper rear link on the KA T5 Watts design is the primary link. As the car squats the rear upper link comes more into play with higher angular forces than the lower can ever create. Looking at the opposite, rebound.  The link rotates to reduce any jacking the lower forward link creates. Being useful in cornering.

This is all theory I know because I never drove a car with a Watts. I still can't figure out how it affects braking and that's what  always had me baffled and still does. Gold star for PJ saying Watts! LOL!

This view you can see the length difference between the two trailing links.


Here you can see how much closer the rear link is to the HS center line.


PJ what more have you read on Watts designs? Does this still have a negative effect on corner handling?

And why are the HS's rearward?  Increases the camber curve? Is it just a placement issue being a convenient location for the differential?

The Milliken 1960 MX-1 Camber Car led me to, Mercedes-Benz F400 Carving Concept Info. However off the topic.
http://www.youtube.com/watch?v=3_4LGvD1V4Q&feature=related

Ralphy

Last edited by Ralphy (10/01/2012 6:34 am)

Something else I see with the T5. The coilover being at the rear. If you understand the upright rotating clockwise when rebounding. Because of the lower trailing rod rotating forward and the upper rearward rod back. This unloads the the inside tires spring at a faster rate when cornering. This causes the coilovers lower mount to fall away as it rebounds/releases. Not only that but this loads the outer coilover faster initially. So you should see less body roll in cornering. If the coilover were to the front of the HS, the opposite would happen. Which would be a negative effect.

I'm trying to figure out the motion of a toe rod behind the HS like the Giovanni C3 design instead of two lower mounting points as the KA T5 camber toe arm. Equal length to the HS and parallel. As best I can see without plotting. Is that the inner tire will toe outward. The outer will stay put. The inner rotates due to the fact the toe rod will drop below the HS again, because the upright will rotate clockwise. The amount should be slight. I need to calculate real numbers. This may minimally promote roll steer.

You win a free trip to Fla. LOL! I've seen that design before, it makes me ill trying to follow the links visually. But for some strange reason I understand what it does. There's a working model, if you click how it works at the link.
http://www.walker-partnership.com/

Ralphy

Last edited by Ralphy (10/01/2012 10:59 pm)

I have enjoyed the way my modified T5 suspension has enhanced the way my mustang corners ever since I installed it.  It is so stable and roll resistant I had no need for the rear anti sway bar I used on the Jag design.  I also abandoned the stock Shelby front suspension and went with a copy of the Griggs GR350 front suspension.  It too made a dramatic improvement over the antiquated mustang design.   Griggs claims to have achieved 2 G cornering forces with street tires when his complete suspension systems are installed in both late and early mustangs.   I have yet to record these same results partly due to the fact I am using much smaller section width tires  however I have gained .4 G on the 300 ft skid pad over the enhanced mustang front with hotchkiss drive live axle rear suspension.. The same 245-45-zr 16 tires and wheels were used for all of my skid pad testing.
   

  By the way.       P.J.  Neat find on the Dax suspension.   It looks like a true original concept and not just another modified example of different spring linkages on the same old stuff.  Very interesting concept. . One concern I see is there would be a change in toe with the movement of the upper control arm. That would generate bump steer.

Last edited by tyrellracing (10/04/2012 6:22 pm)

Back to the Watts link. Now that I better understand how it directs force. I'm also noticing the Jag with a LCA and a upper Watts creates a very neutral effect. Since the forward link cancels the back link and the reverse.


http://s350.photobucket.com/albums/q401/acmjg/?action=view&current=MOV04917.mp4

Ralphy

Last edited by Ralphy (10/05/2012 7:30 am)

When I changed my Jag IRS to the modified t5 I extended the upper or rear link mount on the upright so the link connection was the same distance from the axle CL as the lower link connection . Then I lowered the rear frame mount so there was a tangent line from the front frame mount to axle CL to rear frame mount at normal ride height. This created a true watts linkage that with the suspension travel produces no fore and aft movement. This also equalizes the loading of the front and rear links.
       This is why I stated the KA T5 toe change graph did not apply to my set up.
  When I built my uprights and frame mounts I put 5 mounting holes on one inch centers on each so I can go back to the exact same geometry as the T5 or a variety of other combinations. That is why I described my design as being tune able.  This is how I generated the numbers Ralphy claimed I guessed  months ago.  My current set up does not generate a change in toe nor roll steer of any amount worth mention with travel.   
   The whole reason the stock T5 produces a change in toe at all is because the axle is not centered between the forward and aft linkage mounts on the upright. Since in stock form the T5 axle is not centered the front and rear links cannot cancel each others motions out
    The forward and rear links on the T5 are not different lengths.  The image might make them appear that way but in reality the only difference in length is made up by the adjustment of the heims.  In stock form the rear link of the T5 carries the majority of the loading in the fore and aft directions. The rear link also has the weaker mounting point
   

     When I was satisfied with the Griggs suspension I built and set up on a spare mustang nose, I changed my Shelby over to the Griggs GR350 front suspension. This required that  I change the single T5 lower control arm per side to a twin LCA per side on the T5, When combined with new inner LCA mounts  allowed me to move my roll center to a location that would complement the Griggs front suspension. It also made toe change much easier.   I still use 4 coil over shocks on the rear suspension with one on each LCA.  The rear units have 260 lb/in and the fronts have 140 lb/in spring rates.


     Getting rid of the roll under steer Klaus Arning put into the T5 rear suspension was required to have predictable high speed cornering.  Roll under steer generates some serious undesirable traits in the transient portion of corner entry.    The roll steer effects of the T5 may seem to seem useful on paper but they can be deadly in a wide sweeping 120 mph corner entry

I did not mention that with the relocation of the lower control arm came a change in ride height. That was the only way I could keep the control arm level with the new ride height. The lower control arm plays no role in determining the roll center.  Ride height does.
     Your assessment of the change in toe is flawed because with out measuring my actual set up you cannot locate the rear link frame mount nor can you determine where the upper mount on the upright is located nor do you know my ride height.  Not knowing any one of these points would throw off your math. Not knowing all of them makes your efforts pointless.   Your math based on guessing has little meaning.  Nice try but but with out putting a tape on my car you can only guess.  Every number you based your math on is wrong.  Keep in mind my half shafts are Jag and therefore longer than the T5 image you scaled. Not only that the T5 image you have is from a 65 mustang. Mine is a 67 and is larger in nearly all dimensions  Posting your guesses as some type of proof is at the very least is rude.   
    When I set up my Hunter laser alignment heads on my rear hubs and aim the laser on a target at the front of my car the laser dot is aprox. 3/32 in dia. With 4 inches of travel, 2 up and 2 down the laser dot does not move more than 1/16 inch.  This measurement was taken more than 20 feet from the light source.  In all reality that is an insignificant amount of change.  That is far less than your .286 degree
   Have you even built your IRS or are you still talking about it?

When did I declare any angularity dimension of the front link?  If I did ,and I doubt it, The ride height  has been changed enough times since then to make such information obsolete.  I have even built another set of uprights that do not have tapered roller bearings for the LCA.  With 3/4 Heims on the LCA's the bearings in the upright becomes redundant.
      The first set are going into my Sunbeam Tiger. The Tiger will be my second IRS conversion.  I just finished the replacement of the Tiger's K member and built a front suspension that is virtually identical to the Griggs racing design I built for my mustang.  I already had the welding fixtures.
     The line from the front mount  through the axle CL to the rear frame mount is within 2 degrees of the road surface depending on the front to rear ride heights.
   
    I own an inclinometer and use it often at work to double check my sine table setting. It is guaranteed accurate to .0001 per foot.  That's the manufacturers description not mine.   but I don't recall having ever measuring something as pointless as the angle of my front link.

TR you said,
"When I changed my Jag IRS to the modified t5 I extended the upper or rear link mount on the upright so the link connection was the same distance from the axle CL as the lower link connection . Then I lowered the rear frame mount so there was a tangent line from the front frame mount to axle CL to rear frame mount at normal ride height. This created a true watts linkage that with the suspension travel produces no fore and aft movement. This also equalizes the loading of the front and rear links."

Huh!

Your front trailing link goes downward to the upright as you stated 2 degrees. Your rear at best guess as you stated months ago goes upward at 10 degrees to the upright. Above you say you have no fore or aft motion at the wheel. Your front lower link travels a short bit to zero degrees and then starts back in the direction it started in under jounce. IT REVERSES! Then the rear is at app. 10 degrees and keeps increasing it's angle, moving rearward more rapidly than the front lower. But again your saying your wheel centerline never changes? LOL!

A motionless Watts has to have both links in the same direction at the same angle. Then you won't have any fore or aft motion. Just like in this video I had posted earlier.

http://s350.photobucket.com/albums/q401/acmjg/?action=view&current=MOV04917.mp4

As best I can tell what your describing, your wheel center moves rearward 6 degrees at jounce.

Ralphy

Last edited by Ralphy (10/09/2012 3:50 pm)

I said my best guess. That is not a statement based on measuring the actual angle.  My ride height is not as high as it was then primarily due to the changes I did when adding the GR 350 front end.   Your numbers were wrong because you dont have access to my vehicle and with out that you are wasting your time.   Mean while I am driving it to work daily for as long as the weather holds.
   I wasnt aware I was suppose to lead you by the hand through the steps I went through when altering my set up. Every statement I made was accurate at the time I said them.   The system I have now has little resemblance to what it looked like when I first altered it to the T5 config.
    My uncle was the west coast track steward for SCCA.  Through his contacts I was invited into a few doors that otherwise would have remained closed. This enabled my brother and I  access to the SIR and PIR tracks on all the test and tune dates as well as some time on race days during practice.  I no longer compete in the vintage class due to the value of my Shelby and the increased risk factor of having someone crash into me.  During these events I had access to some very nice mobile  equipment and when their facilities were not too busy I was granted shop time. Through this I had access to. Lifts, scales,  alignment computer, suspension analyzing soft ware and so on. I made more alterations to my front and rear suspensions last summer than I have time to type.
          To answer one of your questions
   Yes when I went to the T5 LCA I machined a lower mount that moved the mount two inches forward for the single control arm. I Started with a pair I built on center with a different pair of LCA's but they wound up rubbing on my brake rotor when the suspension was compressed hard which is why I built the 2 in. offset ones.  More recently I went to twin lower control arms with a coil over on each and that is the LCA set up I am going to keep.  I have been through three different pairs of  rear frame mounts and moved the upper mounts on the uprights once to find a geometry that provides the best turn in characteristics.  I have set the alignment with zero toe, toe in and once by mistake toe out as well as a few different camber settings usually from zero to around one degree neg.  When I had access to the skid pad I went as far as 1.75 neg front and rear static camber with very little benefit over .8 degree. I found .8 neg to be optimum with the tires I had.   I have built three sets of steel uprights. Two with tapered roller bearings for the single LCA's and one with a plain .749 hole for a press fit 3/4 stud for the 3/4 heims in the new LCA's. The second bearing type upright was built due to the desire to increase the negative camber gain. The upright with the plain hole has the same geometry as the second bearing type. On the track I was using less than 2 inches total travel and the amount of neg camber gain the Jag upright design provided was negligible. I have built at least a half dozen links for the watts link in different lengths.  This allowed me to set the uprights perpendicular to the road surface, angled like the T5 drawing shows as well as moving the wheel location in the fender well. I also built an extra set of LCA's and half shaft spacers to increase the track 2 inches to match the new front track width.   The rear shocks are AFCO 1375's that I cut down (-3in.) machined and rethreaded all the parts required to make them the same length as the Jag shocks. Since then I have revalved the AFCO's twice and    I tried a variety of different spring rate combinations.
   That was the readers digest version of last summer and a little beyond   Did that get you up to speed there Ralphy?

Last edited by tyrellracing (10/10/2012 12:48 am)

The fact is you stated you have NO toe change with trailing links coming from opposite sides. THAT IS IMPOSSIBLE!  I don't care where or what angle you position those two links. The upright will rotate and cause toe change. Here's another question, with dual coilovers and twin toe/camber rods where did you mount the coilovers? They can't be mounted now to these rods, since they change relation to each other. You can't build any type of solid mount between these rods/links. You can't mount a coilover to a single link with any type of bearing end. Hint TR! This is where you say you built alternative/more uprights that work like the Corvette. You mounted the coilovers to the upright. Yeah that's the ticket! Oh crap, but now that means you would have to have built new upper coilover mounts since the coilovers are out further.

Fact #1, you can't make an upright not move fore and aft and at the same time not rotate. Which you claim you've done. You can do one or the other but not both at the same time

Fact 2, to build as you say a true Watts link. In order for the center/wheel to stay stationary. Both of the links have to be at the exact same angle in the same direction. Your rear link is up to the center, your front is down. You said this, so to try and say I don't know exactly what angles you have. I do know they do not point at the same angle.

This is still funny, "I own an inclinometer and use it often at work to double check my sine table setting. It is guaranteed accurate to .0001 per foot.  That's the manufacturers description not mine.   but I don't recall having ever measuring something as pointless as the angle of my front link."

Then when you get into this positioning and rotating and moving fore and aft? What happens to your camber curve as someone else mentioned? It's a mess! That's one of the reasons I posted about possibly using the KA trailing link design with a C4 style toe link. It allows the camber rod to be the camber rod and the toe rod to be the toe rod. Plus it makes the upright rigid at the halfshaft.

With today's electronic technology and abilities. I still find it strange you can still not post any pictures. You said you would months ago. You have cash to do so many things but you can't buy a new cable to attach your camera to your computer. All your friends can't take some pics of what you have done and send them to your account. As much as you like to beat your chest with all your revolutionary designs. Surely you would want the whole world to see all this handy work.

Last edited by Ralphy (10/10/2012 7:18 am)

LOL!

Ralphy

Bottom line.  There isnt enough rotation in my uprights due to the distance the fore and aft links are separated. If the line from the front mount , through the axel to the rear mount is straight and equidistant then the links have to be at the same angle.  The amount of travel I am using has a direct effect on all of the movements and you are clueless what that is.  Go back to the porn site you came from.

Now my heart burn in regard to the T5 is the rearward trailing link. How does it work under braking? Will it cause the rear to want to lift? To me it would seem easier to raise/lower the rear of this link than to raise the point at the upright? Simply make a chassis mount that has a series of positions vertically changing the rears angle?

Another note the T5 resembles most conventional IRS geometries as this C4 diagram. Lower angled for anti squat upper close to level. A double wishbone similar. However it's points are fixed having no angular change. Back to the C4 it's all the same except the upper is flipped which to me would do the exact opposite of the C4's upper?  Seems the C4 would work better for anti dive, since as the rear lifted both links would increase their angle. Or does the braking effect actually push on the upper? Like the fronts anti dive? Hmmm..... So wait a minute, does the T5 design work well in conjunction with outboard brakes? If the rear begins to rise under braking the attempt thru the rear link will want to pull down on the chassis?



I'm not trying to be a smart azz here. But I'm thinking it was maybe, truly designed for outboard brakes? To counter the effect at the rear with inboard brakes, seems it would be easier to lower the rear of the rear link. Or raise the front a tad and lower the rear a tad? With inboard brakes the upper needs some angle with outboard brakes you do not? And TR I am and have noted you angled the rear which would be in the proper direction. Some day I'm going to root you out to post pictures.

Ralphy

Last edited by Ralphy (10/11/2012 10:21 am)

I do not envy your position enforcing rules that seem cruel to those that truly need them to be flexible   However the only way rules can be fair is for them to be enforced the same for all concerned.  It is sad that the rules cannot be written with some flexibility for the bed ridden and those who become invalids.  I would be torn with the task you had in refusing your neighbor the ability to make the necessary changes so the individual with the annurism could live the remainder of their life in the comfort that the remodel would have provided them.
    As the devils advocate I also understand the need for such rules to protect property values.    I am sure the rules cover more than additions that make  homes  look like hill billys built them.  I have to believe that you did not have this scenario in mind when you accepted the position.
   That said,     I have always considered  volunteer work to be accepted only  when a surplus of time is available for the task.  When the time is not available I simply do not agree to volunteer.  This small portion of common since will allow the volunteer work to be performed with out interfering with ones domestic life.  For this reason I have to consider the use of volunteering your time to be a poor excuse for short comings in your own tasks.
 

    I believe that it would be impossible to determine a individuals personality type by their posts on the internet.  That would be like reading a book by the picture on the cover.  I was wrong in some of my statements concerning toe change.  Not because I had intended to miss lead but because my method of measuring it was flawed.  But then again many of your broad statements were wrong as well.  Your first few free body diagrams were not even close to representing the watts linkage under my car..  The world is not as black and white as you seem to interpret it as being.  Your reasoning behind the change in toe was not with out merit however it was still incorrect.  Life is too short to argue with someone I dont even know.  So in my opinion the best conclusion is to agree to disagree and leave it at that.

Last edited by tyrellracing (10/15/2012 6:20 pm)