GENE :Jim, I think Norval took about 3-4 posts to hammer home that we need to extend the TOP of the spindle, effectively, by getting longer stems on the ball joints, not just raising the arm position...have to raise the top PIVOT CENTER, not just the control arm angle....

Jim, that’s why I was saying lets order the spindles that will incorporate everything we need to perfect our front suspensions, I would like Taller Spindles not extended Ball Joints or Spacers if possible. It’s the same theory just different approaches. Did you see where Norval said we need to find a suitable tall donor spindle? If there is not one then as someone earlier said “Why not make one?” G-body cars use Impala spindles and shorter upper a-arms to accomplish this as well.

Marck, what we need is to make the spindle longer so that the ball joint on the upper arm is in a plane ABOVE the cross shaft, only THEN will the lines you draw through them (and lower arm) meet inside or just outside the opposite side of the suspension. Dropping the suspension will put the wheel center higher on the spindle, which makes the roll center sit higher above the ground.

Jim, What I meant was that the hub could be positioned as needed to lower the car and not affect the geometry of the suspension.
Marck, as for bump steer, bump steer is caused by different geometry between the steering linkage and the control arms and steering knuckle on the spindle.

Jim, my thoughts were the same and as I was saying the steering knuckle could also be positioned appropriately to help address the bump steer issues while we are asking for a spindle. VBP sells a bump steer block set that does what you are saying. Why not just order a taller spindle with all of our applicable needs such the steering knuckle located where it does relate to the geometry between the steering linkage and the lower control arms and steering knuckle on the spindle. Then allow the hub to be located at a good position for ride height.
If your friend used S-10 spindles and front steering, then the Impala spindles will work for our Corvettes as a taller spindle. The G-body guys and the S-10s are both using them to accomplish a taller spindle. The only problem is I would have to look at the front steering and the steering box relationship or look at a front steer rack. I was looking at a Dodge Dakota front steer rck the other day with this thought.
I was referring to all of this earlier when I spoke of a donor spindle being used with the custom a-arms. I can adapt any type of ball joint to them that bolts in and use a spindle that is better suited to our Corvette. Jim
:smash:

 

It would be cool if the C5 stuff would bolt in... with some cutting and welding it wouldnt be to hard.... do almost a subframe job.

Would nascar a-arms help? Theres a place down in mooresville... i think, website used to be Bid Racer, they were in one of the mags a few years back... they used to stock all sorts of em. That and whopper brakes!

TTT! (incase i didnt add anything :lol: )

 

Twinney, this is very interesting to me, but also I find my own situation very limited with the information you are providing, and Pete 79 not sure of his handle....at any rate, I still have to finish acting on his suggestion of raising my tie rod centers.....I do notice the Steeroids system has a plate on the center rack with the tie rod ends upward of MY position(s) and also the position is much wider, further apart than mine......so I wonder about how much torque is applied to that rack center output trolley, and if the forces would cause problems/weird wear over time....I am willing to raise the tie rods about 2 inches higher than the bolts, and so on...but making the separation any wider also.....well....I just dunno...and I am wondering if I want to remake the tie rod collars yet again....
I wonder just how much that would ultimately buy me....

GENE

 

Cough... may have found some spindles for us... customs for stock cars
http://www.stockcarproducts.com/susp18.htm

 

This is good stuff. :thumbs: :iagree: with chris o. I'm still considering the possibilities.

 

heres the link to the main page for the lazy... ME!!
http://www.stockcarproducts.com/

 

Hi guys. I am on holidays Thursday and Friday so I don't spend time here. I aligned the vet this morning and with the caster camber gage it is easy. I ended up the caster 5 degree positive and camber .5 degrees and toe 1/16-1/8th. The gage can also be switch from side to side to show the difference. If one side is 5 degrees and you move it to the other side which is only 4.5 degrees the gage with read .5 difference, It is really a usefull tool. Any one who works on suspensions should have one.
Anyway back to the taller spindles. Why don't we make our own?
They are made of cast steel stock which welds beautifully. The stock car guys do it all the time. I work in a research department in welding and I work with so very very knowledgable guys and they say it is not problem.
It is no problem to build a jig to hold the stock spindle and then after cutting extend the jig to the new length and add a piece. Well not exactly.
I would cut the stock spindle off near the top taper and take a donor spindle from another full size car, cut it off leaving the extra length that I want for my new spindle then graft the two together.

Both cut surfaces are sharpened like pencils and the two points are put together and with a mig welder you start filling in slowly. This way you get 100 percent penetration with not crack in the middle.
I built my own pitman arm with welded joints, 2 of them to be exact.
By using a donor spindle you reduce the welding to one joint.


I know this would work. I would take the original spindle off the car, build a jig to align the tapers by using the studs that coleman sells for my take apart ball joints, I then extend the fixture say 2 inches and cut and sharpen to a point the original spindle then take a donor spindle , leave the extra on it, cut it , sharpen it and place it in the fixture on the taper stud that aligns it.

I have faith in a proper welded spindle and Roger my friend the stock car racer who has a special car just for Watkins Glen does this all the time. He showed me a few welded spindles that he has in the shop. He uses oldsmobile spindles and has them welded with different extensions. You can just add a piece but that doubles the work of welded 2 joints per spindle. He goes the donor route himself.

Since my car is ready to run today I will not touch it again until fall, but this fall I will take the spindles out and do this, adding at least 2 inches right away or maybe more after I think about it.

I will be back to work Monday so I will not be on the forum much before then to defend my thinking.

With the modern mig welders and no flux this is very easy to do. Maybe this comming winter we can get and little business going of helping each other get these modified spindles. I know I could do it quite easily if I want to.
And I do but not until next winter. It is another project to look forward to.
As for bump steer that is a whole other problem and I might start working on that soon.

I too am enjoying this discussion but when I am on holidays it means working on the yard, working a little on the vet, going for a ride each afternoon on Strider and little time here.
I will be glad to get back to work so I can spend time here.

 

ZD75blue. Those would be great spindles but who could figure out exactly what we need? I certainly could not. The price per pair is about $500 Cdn and that is getting pricy. I am still convinced that I could weld up a pair for next to nothing and once the jig is made it would be no problem producing them for others.

 

Norval, thats a great idea. The crucial question is 'how much to add?'

If you move the roll center to close to the center of gravity, the front will not roll at all in a corner and will ride hard as a rock. Someone has to break down and buy the suspension analyzer program. I myself am saving up for a tig welder!

Chris.

 

Hmm... anyone proficient in a solid modeling program? Maybe if you used something like solid works, you could look at the angles if it's a floating drawing...

Unfortunetly, I can't finish the second learning stage... the second demo drawing! Dont feel bad for me... I'm just not an artist nor mathematician :cheers:

 

Norval, When we were kids we used to build them for our old shoe box chevys '55-'57s and weld two together as you stated and believe me we had tall spindles. We would jack the front end up about 3-4" with them.

Still scares me to think about them, but I never did break one.

I would like to think that with a well designed set we could use them for a core and have someone make several sets for us first class.

Marck, I would like to look at the Impala spindles and see if I could go front steer with a Dodge Dakota R&P. I still am not sure it will work.

Here is the Fab Sheet from Stock Car Products, They are $250 and another $79 for the steering arm, PRICEY!

http://www.stockcarproducts.com/susp18a.htm


[Modified by PROSOUTH, 9:41 PM 5/8/2003]

 

You know, guys the donor spindle thing may not work, as our vettes have the lower ball joint inverted from the usual position....the arm is above the lower part of the spindle.....most cars I have seen have the arm below the spindle...consequently our ball joint studs point down to the ground, making the taper in the spindle go the opposite direction , therefore making another car spindle to fit is even MORE complicated than cutting/welding ....
I think to go to my local Auto Zone which lets me into the bins....and go looking for a matching LONG stem ball joint for the top a arm and find a way to mount the damn thing to the arm....
I know ball joints like tie rod ends have 2-3 differant tapers to them, dunno why, just do....

GENE

 

Chris. If I was ready to do it I would talk to Roger and get his opinion. It is alot of trial and error. I would probably go for 2 inches. Our roll center is below the ground, which is where Indy cars are. I work with people that really know suspensions and design Indy try cars every year. The university has a team with a very large buget and they start from scratch and build an Indy car. They are pulling 1.5 G in the parking lot going around cones. They are always will to talk.
Roger has alot of books on the subject plus 30-40 years experience. 20 years ago he figured this out on his own and it gave him an edge that kept him number 1 but now with specialized shops setting up the suspension for others he has fallen behind or at least equal.
I will not do it until next fall so my then I will have to figure out how much.
You will enjoy the tig welder. I have one and use it on stainless exhuast systems and roll cages. You need argon gas also.

 

Prosouth. If I welded up a set of spindles and worked on them a few minutes with a grinder and then a little filework and paint you would be hard pressed to tell they were modified.
To me the easiest way around our problem is cutting and welding. To have someone design a spindle or try to adapting another spindle is alot harder then taking a spindle we already know fit and just extending the top.
It does not have to be any harder then that.

 

You know, guys the donor spindle thing may not work, as our vettes have the lower ball joint inverted from the usual position....the arm is above the lower part of the spindle.....most cars I have seen have the arm below the spindle...

mrvette Who cares about the lower ball joint. It has nothing to do with our problem. We have to extend the top ball joint, leave the bottom joint alone. I would cut off the upper taper and add a new longer piece with the upper taper . I would only be working with the upper few inches not the lower part.
If the donor didn't work I could add a piece but I prefer a donor idea better.

 

?/ what do you mean here? Are you trying to minimize bump steer on your rack and pinion setup? You have a center steering one (whole rack moves) like the steeroids one right? If so, the BEST way to minimize bump steer is to position the steering rods so that they are absolutely horizontal when the suspension is sitting with full load on it. When the rods are horizontal they will have the least "length" change. Look at it as the center of a cricle, the part of the circle closest to the 90 & 270degree points are the oens w/ the least change.


Here, look at my little pic (again ;) ) the green is ideal, the other ones are not. With the same amount of vertical movement of the suspension red and blue will give MUCH more "length" change and therefore a toe change.



Marck

 

nice.. that resize thing is haunting me again, it's not showing the picture.




[Modified by Twin_Turbo, 4:15 AM 5/9/2003]

 

Marck, I see and understand that detail on the bump steer now, something I overlooked in my initial install, under correction proceedures pretty soon, again....#2 attempt also failed, can't get whole car to welding buddies, on account of he had neighbor troubles, so we sneak parts in and out of his garage, makes things hard to visualize in spite of my best attempts, but THIS time is a charm....;-)))

OK Norval, I was referring to the useage of 'other' spindles from other cars, and thought of that inverted ball joint, that's why we can't do any other spindels....I know you want to lengthen the spindle, I have no troubles with that my buddy can do that too, but the obvious troubles are much greater than IF I spend some time to find a long stemmed 'rose' of a ball joint at say Auto Zone....

GENE

 

850 posts [100%]
Fremont, ca, us

Re: Norval, A arms (norvalwilhelm) 9:11 PM 5/8/2003


Norval, thats a great idea. The crucial question is 'how much to add?'
If you move the roll center to close to the center of gravity, the front will not roll at all in a corner and will ride hard as a rock.


Chris Ride quality has nothing to do with where the roll cente is located. It only affects how the car behaves in a corner. There is an center of gravity which I haven't a clue where on our cars but lets say it is the center of the crankshaft, we have the roll center which is blow the ground under the center of our cars. The distance from the center of gravity to this roll center is like a length of pipe or a bar, an imaginary bar. When we corner this bar is prying on the center of gravity causing the car to lean into the corner.
Take the bar away and the car rides flat around the corner with soft springs. Roger told me to move my roll center 3 to 4 inches above the ground. To do this the line drawn through the lover A arm pivot points and the upper A arm pivot points must fall inside the opposite tire.
Twin Turbo explains it best with is pictures.
The ride quality will not suffer from raising the roll center.

mrvette bump steer is a whole different problem not solved with the longer spingdles. Even the attachment points on the spindles need to be CURVED. The acherman effect causes it's own problems, the curved sprindle attachment point cause another problem. Between the 2 problems they cancel each other getting rid of pump steer. Without the curved sprindles you are always subject to ackerman.

To those that don't know what Ackerman is it is WHAT? I know what it is but when I come to explaining it I run into problems. Twin Turbo?
The alignment of the rack with the outer mounting points suddenly change as the wheel is turned causing a sudden jump in toe out. The spindles mounting points for the steering is moving in an arc and when everything lines up perfectly the toe out suddenly jumps up to 1/2 inch then when you turn back to straight the alignment goes back to less then a straight line and the toe jumps back to normal.
Curved spindles cause a toe in condition, Ackerman causes toe out. The 2 cancel each other in a turn and that is how the factory gets around Ackerman.
Don't know if that help anyone but that is what it is.

 

Pooh, Ackerman is pretty hard to explain if you've never seen it before. Brittish Cabs all use ackermans, that's why they can turn the tight corners in London so easily.

Lemme do a drawing, and if you don't get it ask away

In this drawing, the black rectangles are the wheels in a corner with conventional steering, the inner and outer wheel are parrallel and want to take tk same semi circular path, however the inner wheel circular path has a smaller radius than the outer one. This is where ackermans comes in in the right , the inner wheel is NOT parallel to the outer wheel so they each take the best route.



Whenever the steering knuckles are at an angle to the lengthe axis of the vehicle you have ackermans, the C3 corvette steering system does not have this feature. The steering joint (center link to knuckle) has to lie closer to the center of the car than the spindle balljoint center.

It is NOT true ackermans. True ackermans is when you draw a line through the stering knuckles and their crossing point is right in the middle of the rear axle, this results in 0 toe on cornering. Less Ackerman is when the steering knuckles are at a shallower angle towards the length axis (crossing point behind the rear axle). This gives Toe in on cornering. More Ackermans is the opposite, and gives toe out on turn in

zero toe:




toe in:




toe out:





shootIT!! I HATE THIS RESIZING THING!! IT irritates the hell out of me, it's not user friendly, sometimes the pics don't show and now they are resized like crap. UGH :mad :mad


[Modified by Twin_Turbo, 8:26 AM 5/9/2003]


[Modified by Twin_Turbo, 8:34 AM 5/9/2003]


[Modified by Twin_Turbo, 2:05 AM 5/10/2003]