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TinManSC92
08-15-2010, 10:38 PM
designed an actual fix to eliminate wheel hop that does not interfer with the handling characterstics of our cars design. Living in the northern climate doesn't make sense for me to use hardend replacement bushings. - ( Don't know if I could handle the annoying squeaking for eight or nine months of the year.)
Plus, this new design eliminates further lateral wear to the interior bushings and, prevents the LCA's from wanting to leave with the car out the back with any quick take off.
Even if the driver doesn't spin the tires, the appiled, or, the "more direct force" of the 5 speeds cause the LCA's to move backward allowing the rear end of the car to squat down. these new anti thrust/ vibration control arms transfer the energy directly to the rear wheels without having to go through the suspension first. the suspension reacts after the tires are moving not before, which in turn, makes for more quicker start times.
For 175.00 bucks and 5 min. of installation time I can't figure for the life of me why these haven't been for sale 20 years ago.
What are some of your thoughts?

nanatothesixth
08-15-2010, 10:49 PM
sounds good!

DLF
08-15-2010, 11:50 PM
Actually, with stock bushings, the LCA's / Knuckles / Wheels move forward during hard launches.

Got pictures of your invention?

BTW, Delrin bushings don't squeak, at least mine don't. The ride is certainly firmer though.

XxSlowpokexX
08-16-2010, 12:07 AM
my delrins defitely didnt squeek..Its the poly that squeek.

TinManSC92
08-16-2010, 12:22 AM
In reality, don't you mean spring forward. That's what I meant by saying you actually leave your LCA's behind out the back, then tighten and spring ahead which in turn causes the first hop. And then resonnace( vibration )takes over. And we all know when a certain action starts it's hard to stop... if ever.
More on the physics of this later. I will first post up pictures with an installed example so I can hopefully attempt to explain the math I used for both dynamic and impact loading. Oh! and I can`t leave out resonnance( or vibration).
BTW This would be easier to calcuate if someone had the actual values of force being produced. I assumed a force of 5000lbs. shear for the suitable shear pin I employed in the design.

TinManSC92
08-16-2010, 12:28 AM
I didn`t know that Damon. You didn`t tell me that last time we talked. However, I still want to launch this car before I change out the sub frame bushings we talked about. As you said, everyone who did the swap did the LCA`s at the same time so you really can`t tell what`s done what. At least I can`t.

DLF
08-16-2010, 12:31 AM
"cause the LCA's to move backward"

This is what I was commenting on.


In reality, don't you mean spring forward.

No, I believe that under hard acceleration the wheels initially move forward, due to the compliance of the bushings, and then "spring" back.

DLF
08-16-2010, 12:38 AM
I didn`t know that Damon. You didn`t tell me that last time we talked. However, I still want to launch this car before I change out the sub frame bushings we talked about. As you said, everyone who did the swap did the LCA`s at the same time so you really can`t tell what`s done what. At least I can`t.

I installed my Delrin LCA and Knuckle Bushings over a year before installing the UHMW Sub-Frame Mounts.

The reduction in wheel-hop, with the resulting improvement in launches, is almost entirely due to the bushings.

The Sub-Frame mounts add some stability during very hard shifts, and a very minor improvement in launches. They were created primarily because the stock parts are no longer available.

I look forward to seeing your design.

TinManSC92
08-16-2010, 12:51 AM
Oh! I get what you`re saying now, and no! that`s where we differ in our approach. I say that because everyones wheel hop is of different severity. some have said to correct it put good tires on it. but, if 3000.00 dollars isn`t good enough then what is. It was Damon that brought to my attention that his car wheel hopped almost as bad as mine. At lease I`m thinking that mines the worst. then it occurred to me that the spring and shock rates are different settings for different years. (Fast ED Toronto.)
When the LCA`S spring forward they are also lifted back up towards the front because the shocks and springs are also attached to the LCA`s which mean they must be included in the equation. ( the circular motion)

TinManSC92
08-16-2010, 12:54 AM
Not as much as me seeing your sub frame bushings I`ll bet. Hey, by the way, If i`m the first to re order does that make me a 350.00 guy.;)

DLF
08-16-2010, 12:58 AM
Not as much as me seeing your sub frame bushings I`ll bet. Hey, by the way, If i`m the first to re order does that make me a 350.00 guy.;)

Well, I just got a payment for a set earlier tonight, but if you hurry, I'll cut you a break. Should be ready to ship in 2-3 weeks.

TinManSC92
08-16-2010, 01:04 AM
Don`t know how to pay pal yet. Do you take a simple visa or something:o

DLF
08-16-2010, 01:05 AM
Don`t know how to pay pal yet. Do you take a simple visa or something:o

I'll send you a PM.

Hock
08-17-2010, 10:25 PM
designed an actual fix to eliminate wheel hop that does not interfer with the handling characterstics of our cars design. Living in the northern climate doesn't make sense for me to use hardend replacement bushings. - ( Don't know if I could handle the annoying squeaking for eight or nine months of the year.)
Plus, this new design eliminates further lateral wear to the interior bushings and, prevents the LCA's from wanting to leave with the car out the back with any quick take off.
Even if the driver doesn't spin the tires, the appiled, or, the "more direct force" of the 5 speeds cause the LCA's to move backward allowing the rear end of the car to squat down. these new anti thrust/ vibration control arms transfer the energy directly to the rear wheels without having to go through the suspension first. the suspension reacts after the tires are moving not before, which in turn, makes for more quicker start times.
For 175.00 bucks and 5 min. of installation time I can't figure for the life of me why these haven't been for sale 20 years ago.
What are some of your thoughts?

Any pics?????

TinManSC92
08-17-2010, 10:39 PM
Yes. But I e-mailed them to Damon. Not because we we're talking about this a while back and he wanted to see them ( before I even posted) but mainly because I can't figure out how to post them on the site as of yet. Got to call the Wife in for this one. :confused:
added some modifications to them today as well.

XxSlowpokexX
08-17-2010, 10:58 PM
I got tthe photos for some reason this morning. Sent them to my personal email awhile ago..waiting for them to come into my in box so I can post them

TinManSC92
08-17-2010, 11:17 PM
Well, thank you very much for that. I just thought you we're away some where. I probably should have taken the pics. with them installed on the car huh.

XxSlowpokexX
08-17-2010, 11:46 PM
Here ya goooooooo

decipha
08-18-2010, 12:12 AM
hmm sounds promising, anybody else tried these out yet with similar success?

Regul8r
08-18-2010, 09:32 AM
I want to see a pic of these ON the car.

Then would love a before and after video to support the claims.

TinManSC92
08-18-2010, 05:47 PM
Got them installed now...with the correct height spacers. I'll see if Damon will post them up for me again tomorrow.

XxSlowpokexX
08-18-2010, 07:35 PM
didnt get them yet!

TinManSC92
08-18-2010, 09:16 PM
Sorry Damon. I'm going to have to take new pics in in the morning.

RalphP
08-21-2010, 11:35 PM
In reality, don't you mean spring forward. That's what I meant by saying you actually leave your LCA's behind out the back, then tighten and spring ahead which in turn causes the first hop. And then resonnace( vibration )takes over. And we all know when a certain action starts it's hard to stop... if ever.
More on the physics of this later. I will first post up pictures with an installed example so I can hopefully attempt to explain the math I used for both dynamic and impact loading. Oh! and I can`t leave out resonnance( or vibration).
BTW This would be easier to calcuate if someone had the actual values of force being produced. I assumed a force of 5000lbs. shear for the suitable shear pin I employed in the design.

Ahem.

When accelerating the car from a standing start, the wheels will start moving forward. Depending on the amount of compliance in the rear suspension, the car will start moving forward at the same time, or slightly delayed.

This is rather obvious if you actually LOOK at the car when accelerating gradually, then with increasing force.

What will cause wheel hop is when the suspension loads, then the compliant members release the loaded energy, thrusting the car forward, unloading the wheels.

I can dig up the actual physics discussion - but to run the formulas, it'll take some really strong Don'tSleep stuff (that math just puts me right to sleep!)

It's why Chrysler, for years, mounted their solid rear ends towards the FRONT of the middle - the whole spring would work for road bumps, but the short spring in front reduced windup as the torque tried to wrap the spring around the axle.

RwP

TinManSC92
08-22-2010, 11:12 AM
It's too bad you find that math boring. It's what I live for. Moment of Inertia, polar moment of inertia, rotational dynamics, are the things that appeal to me. In fact, LSD or" limit states design" is one of my favorite subjects and areas of design for light weight steel framing.
( now you know how boring I can be and why I purposely stay away from specific terms of physics and engineering. ) LOL!
As for the suspension loading and slight delay you mentioned I believe I've already mentioned that somewhere above. ( I'll have to re read sometime)
Again, in short though, I'm looking at the lever arm, what we call the lower control arm, and it's unbraced lenght factor and stabilizing it so the force of thrust does not go through the suspension first.
The lower control arm is a hinge connection ( pins and bushings) that is designed to move up and down. But, it is also weak enough to allow for lateral movement back and forth when enough thrust is employed. This is what I was designing and implementing on my car. But, I got busy at work with overtime which has temporarily delayed my testing. Coincidentally, I was busy at work installing anti thrust vibration control arms on 20 000 cfm fans at their flex connections. ( see boring... moment of intertia, torsional vibrations, blah blah, blah)LOL!

TinManSC92
09-25-2010, 12:04 AM
Well, thanks to DLF I'm on my original post again ( could'nt tell you how he found it) with my finishing results. IMPRESSIVE. I forgot to mention in the previous post the easier shifting. Not as much binding from 1st to 2nd, but, more importantly the wheel hop is now eliminated as well as any thumping or clunking. As I mentioned earlier, the launch time is dramatically quicker. Almost like a direct drive. Too bad it wasn't raining. I can do much more testing and adjusting and be easier on the car.

I drove around all day to see if I could notice them being on the car while driving on very rough roads to the highway. ( with the occasional fun stop and goes) It's quiet and you aren't even aware they're there. Going to need another set of tires now.

dissasembling them in the AM. to check for bending or twisting. Still got to paint one of them as well.

seawalkersee
09-26-2010, 06:08 PM
Howand where do these attach to the car?

SWS

Regul8r
09-26-2010, 07:25 PM
PLEASE post up pics of these installed!

We are GLAD the math stuff is interesting to you!
If you have finally applied that science to our cars and eliminated the wheel hop MANY of us with be extremely grateful!

PICS PICS PICS!
Oh yeah, and then a write up of what you did!

TinManSC92
09-27-2010, 08:12 PM
I've got the pictures. Now I just need to find another volunteer to upload them to. Don't know how to post them on this site. In fact, I barely know how to use this darn thing. I hate having to use Damon again and again as the go to guy but............... Hello, Xx slowpoke Xx ?

Regul8r
09-27-2010, 09:06 PM
I've got the pictures. Now I just need to find another volunteer to upload them to. Don't know how to post them on this site. In fact, I barely know how to use this darn thing. I hate having to use Damon again and again as the go to guy but............... Hello, Xx slowpoke Xx ?

Send them to me, I'll post them.

torqued247@yahoo.com

Hock
09-27-2010, 09:08 PM
I got them, just working on resizing them so I can post them. Be a few more minutes.

Hock
09-27-2010, 09:11 PM
These are the basic pics

Hock
09-27-2010, 09:13 PM
And these two are of it mounted on the passenger side.

TinManSC92
09-27-2010, 09:44 PM
Yah, that's correct. And, thanks Hock. There's not really alot to see when installed. The first pic. is done by looking through the rim on a silly angle. The last picture shows the installation while car is still jacked up. When they are tightened up and the car lowered they fall down to the bottom of the pin on a 30 degree angle or something like that. The length over their weight causes them to naturally be at rest at that angle.

Still have one more adjustment to figure out. After many launches the sub frame sleeve that the connecting bolt goes through keeps bending. then a slight wheel hop comes back. Not enough to chatter though.

Going to have to employ some some sort of steel spacers inside to fill the void. Hopefully, two plastic bushing might do it.

Might have to go back to a bigger bolt.

Hock
09-27-2010, 10:33 PM
Well being that all the up and down movement should happen at the heim joint would it be better to have as little distance between the upper and lower connecting points at the sub frame? I would think that would help eliminate the movement at that point which is bending the sleeve and the mounting bolt, that shorter distance would be harder to flex compared to a longer distance.

TinManSC92
09-28-2010, 07:09 PM
I don't know what a heim joint is... fill me in a little here brother. If you're referring to the shock mount bushing, that only rotates a little but, certainly won't be enough to match the arc of the LCA. I had to design them this way so the LCA would move freely without pulling the tire out of alignment while it travels up and down the pin. The rotation at the shock mount bushing is more to prevent any additional binding that might arise from hard driving, noise reduction, and a little more travel distance for safety.

If, for example they bottom out, the free movement at that "joint" will eliminate the arm from being sruck in that position until the next big bump as well as eliminate the clunk from hitting bottom. ( I hate rattleing,noisey cars ) Hope that's what you mean.

Plat0ribs
09-28-2010, 08:39 PM
An extremely rigid articulating joint, commonly known as a ""spherical rod-end,"" used in any precision linkage. Heim joints are often used in the suspension links of race cars because they locate wheels very precisely.

I'm very interested in seeing this part mounted and photographed from below while the wheels are supported.

TinManSC92
09-28-2010, 09:09 PM
Hmmm,... Wow! Had no idea. I only used these swivel eyes because I onced employed them into a light weight steel roof truss design I was developing over a decade ago and I knew their weight load capabilities.

What's funny is, about that same time a guy walked into my old office and saw some 1/2 inch shear pins and those swivel eye bolts on my desk and asked me what I was doing with landing gear parts from a cessna or something like that. I thought he was only joking with me at the time. Now that you mention that, maybe he wasn't being funny at all. Apparently, lots go over my head.

TinManSC92
09-28-2010, 09:15 PM
Hmmm,... Wow! Had no idea. I only used these swivel eyes because I onced employed them into a light weight steel roof truss design I was developing over a decade ago and I knew their weight load capabilities.

What's funny is, about that same time a guy walked into my old office and saw some 1/2 inch shear pins and those swivel eye bolts on my desk and asked me what I was doing with landing gear parts from a cessna or something like that. I thought he was only joking with me at the time. Now that you mention that, maybe he wasn't being funny at all. Apparently, lots go over my head.

seawalkersee
09-29-2010, 01:45 PM
What 30* is listed here? Is that the front bolt (on which the heim rides) or the piece of metal that is bolted to the shock?

SWS

TinManSC92
09-29-2010, 05:13 PM
That would be where the hiem rides. The bolt that attaches to the sub frame will be straight up and down.

Regul8r
09-29-2010, 07:33 PM
I am really trying to wrap my head around that set up.
I am not doubting it works, just thinking there HAS to be a better way.

An open heim joint the slides on a bolt? that just says failure to me.

DrFishbone
09-29-2010, 07:53 PM
Bring (or send) a set to the Shootout...I'll give them a good test for you.:cool:

TinManSC92
09-29-2010, 08:28 PM
I'm sure it looks rather unorthodox but, the stainless bolt will hold up. And, with their constant moving they always stay clean. The swivel eye bolt,( or hiem, as you call it ) comes in all sorts of styles and material. ie. greasable fittings. Just depends on the individuals living, driving arrangement. And money. Besides, if you feel that after a season or two they could use some TLC they are awfully easy to get to and uinstall.

I'm happy with the protypes performance and am now making a set to have fixed to my car for good. With that one more revision of course.

TinManSC92
09-29-2010, 09:03 PM
HEY, Doc! How can I get this prototype to you? With some installaion tips.

DrFishbone
09-29-2010, 11:20 PM
Well, the shootout is in two days, so I guess it would have to either be mailed to the hotel or somebody deliver it. If it's simple to install, I may try it on the drag strip this weekend

If you want to just do some testing, I can volunteer my car, as long as I feel comfortable with the installed product. You can send me a PM if you'd

Regul8r
09-30-2010, 08:38 AM
looks like it would be easy to hook up and un hook between runs for comparison runs!?

DrFishbone
09-30-2010, 11:43 AM
looks like it would be easy to hook up and un hook between runs for comparison runs!?

I'm not consistent enough to compare 1/4mi times, but the wheel hop I can probably test.

Regul8r
09-30-2010, 07:11 PM
I'm not consistent enough to compare 1/4mi times, but the wheel hop I can probably test.

Thats what we want to know!
times not the issue...
Can it STOP wheel hop and hold up under hi-power or multiple launches?

TinManSC92
09-30-2010, 09:15 PM
I'm with you REGULATOR. While it's true the car launches harder, I don't care. It's that wheel bashing I'm ticked about. That's primary. Everything else is just a nice secondary extra. I didn't get the time today to institite my fix for the bent sleeve. I should post a picture of the sleeves because they also have deep grooved cuts at the top and bottom of the sub frame holes from the sudden and constant impact.

There's a lot of force to restrain those LCA's to an almost '0' tolerance permanently. But, it can be done.

And, here I was wanting to make these a lot lighter. Ha ha! I think I have to go back to the bigger bolt and heavier bushing at the frame. The high tourque approach to yield more grip on the bolt will not overcome that movement for very long. Wheel hop slowing comes back.That joint has to be a moment connection. at least close to it. Otherwise, the constant pounding from the shock will keep bending them.

Regul8r
09-30-2010, 10:03 PM
My question is this...

Are you using the bracket to hold the LCA from going forward and back?
The long bolt is just there so it can travel up and down along the sleeve as the suspension travels up and down?
IF that is what you are doing then I think there has to be an another solution.

I thought others were working on some sort of arm type connector going to the UCA? To keep the wheel from torquing it forward and back causing the wheel hop.
This seems to be a new way of attacking the hop issue. thinking it is not the twist from the single UCA but actually the movement of the LCA.

Interesting!!

TinManSC92
09-30-2010, 10:34 PM
Well, I'm only going on basic laws of physics. Especially Newtons third law. For every action there is an equal and opposite reaction.

I've read where people say that the problem is because the wheels spring forward. But, that is only the secondary reaction they're witnessing. My question has always been.....what causes the wheels to spring forward in the first place?? That should and was my starting point.

Besides, I've already tested my reasoning ( see theory ) and, with some fine tuning I think we're off to the races. :D Unless of course, something else happens that I didn't consider through too short sighted reasoning. Done that lots. :o

TinManSC92
09-30-2010, 10:50 PM
Re read your question. YES, the LCA's Are deffineatly not designed for the force produced by 5 speeds. Truth is, drive train ressonance has absolutely nothing to do with wheel hop. It comes down to good ol' American tourque.

Remember! Car engineers do the best they can with the money ( time ) alotted to their division. They're design just needed a little more TLC. That's all. The autos just don't have that sudden and direct impact by dumping a clutch. :D

RalphP
10-01-2010, 01:46 AM
Well, I'm only going on basic laws of physics. Especially Newtons third law. For every action there is an equal and opposite reaction.

I've read where people say that the problem is because the wheels spring forward. But, that is only the secondary reaction they're witnessing. My question has always been.....what causes the wheels to spring forward in the first place?? That should and was my starting point.

Actually, look at the thrusts again. The wheels should drive forward and spring back.

I mean, the body is at rest. With traction, the wheels start forward. The body has to catch up to it. The wheel hop is when the wheel pops back breaking traction, right?

RwP

XxSlowpokexX
10-01-2010, 02:42 PM
I can see this as something to use on the track then taken back off for street driving. I cant see the design holding up to daily driven abuse or under normal street driven conditions. Dan Sly should comment more as he had something he was trying out as well.

TinManSC92
10-01-2010, 09:12 PM
Hi ya, Ralph. I did read your post and didn't have time to respond till now. Yes some of that is true. But, the last part I find contrary to popular belief. I say that because the wheels do drive the body just not all at once. our car bodies are not monolithic structures. ( acting as one on it's own ) Good platform and fairly close to it. But, they are basically supported by our suspensions. Our suspensions are all connected together by hinge connections which allow for the neccessary movement. These moveable joints must tighten up first when driven by thrust before the body can move. So, the wheels have to be falling behind the body a little bit at first. then momentum makes it grow every bounce until the joints reach their maximum stress and restrain the movement. ( or until something snaps )

Also my car doesn't wheel hop on ice, which means drive line ressonance must be ruled out. NOTE; harmonic dampers do not balance out driveshafts or anything else completely. only balance shafts out to their normal opperating range of RPMs. Yes, even in engnes. more about backing up in a minute.

TinManSC92
10-01-2010, 09:21 PM
SLOWPOKE! Why aren't you at the shootout. And, to answer your last comment. I haven't got an answer :D I can only say that the grade of stainless should hold up better than the rest of our exposed components under there.

YES! It all comes down to the weather. The whether or not they hold up:eek:
ha ha!

TinManSC92
10-01-2010, 09:31 PM
P.S. Who is Dan. Never heard of him. I don't think. But, yes! that would be nice. Or, anyone else working on this. Of all the 5 speeds out there you would think more than 4 or 5 guys would have some input or ideas wouldn't ya?

TinManSC92
10-01-2010, 09:39 PM
Ralph. can only type for so long before I automatically log out. Stupid router. If what you're saying is true it's still ok. The brackets will restrain that movement as well. More on that later.

seawalkersee
10-01-2010, 10:56 PM
P.S. Who is Dan. Never heard of him.

Dan Sly. Big Daddy.

SWS

Hock
10-15-2010, 11:33 PM
Sooooo, what where the results?

TinManSC92
10-18-2010, 11:34 AM
Sorry! Just getting back to this after changing out my entire front end and brakes. Didn't do the sway bar bushings as of yet though. But, while I was getting the alignment done I noticed that the nuts on the lower shock mounts had backed right off ( never tightened them ) causing the shocks to move far ahead.

It's important for me to recognize how firm or tight I can have these arms without changing the caster on the rear end. ( caster is how far ahead or behind the wheel sits at center line - to avoid any confusion)

I'm at the point where I can eliminate the front nut on the eye and snug up to the base of the eye for a standarized application. Also, to what extent it will effect the firm ride sensor if at all.

More on this tomorrow. I hope!