ecotec swap (Page 69/98)
wftb FEB 07, 07:21 PM
So after about 2 hours of marking , measuring , erasing and re-marking , putting the bracket on and off I finally went for it and drilled the hole that holds the rod end .I just figured if I got it wrong , I can make a new bottom for the bracket .Put the bracket on with the arm bolted in and made some marks so I could see if It moves out of position while the suspension goes up and down .It stayed put , so that was a big relief .I used the mock up arms and bracket to keep it all lined up as the assembly went up and down .So they are good for something after all . Now I can reinforce the area around the rod end and start figuring out the upper arms . I have decided to buy some ready made SPC arms that utilize a Chysler style screw in ball joint .They are adjustable from 7 - 9 inches and available offset and angled or straight ball joint mount , whatever you want .
wftb FEB 14, 01:42 PM
Except for some cleaning up and painting , the bumpsteer arm assembly is now done .I also purchased some Heidts Mustang 2 tubular A arms .I was going to use SPC arms but 7 " was the shortest they make and that is about 1/2" too long .The Heidts are 8" but very easy to cut and shorten .Final finished length is 6.5 " . It would have been nice to use the arms as is but there just is not enough room .Bumpsteer stuff:
wftb FEB 14, 01:54 PM
Arms , showing difference in length . Other than the length , these arms have a great shape with lots of room for the coilover .Camber adjustment will be by slotted mounts , similar to a Mustang 2 custom suspension .
wftb FEB 15, 10:18 AM
I spent some time last night catching up on DonP's racing fiero thread and I was trying to figure out how to make the strut stub stay where it needed to be and I did what they did : welded in a temporary brace .A small floor jack is still maintaining the height and a piece of tubing was ty wrapped in place to simulate a strut .At this point , camber is sitting at +1 .A good enough starting point to make the bracket that hopefully will give an adjustment range of +1 to -3 degrees .

[This message has been edited by wftb (edited 02-15-2015).]

wftb FEB 15, 04:54 PM
Spent today coming up with something to attach the ball joint to the spindle .I think I have something workable and it puts the A arm in the area I want .Doing a little more research in to upper arm angle and how much anti squat I want .A new ball joint lets me angle and tilt the arm any way I want to take measurements and it will hang there without support.Some measurements need to be taken so that the mounts are oriented in relation to the frame the same as the lower arms .
wftb FEB 16, 02:10 PM
So now that the spindle to ball joint adapter is complete , I need to start thinking about the geometry aspects of this build .The book I am using is Herb Adams Chassis Engineering and it has a lot of examples of right ways and mistakes and models drawn out of suspensions that work .Mostly devoted to racing suspensions but the dimensions give me a staring point anyway .The things that can't change :
1-the lower control arm length (12") and the way the inner pivots are angled to the chassis
2-unless I hack off the top of the strut hub and do something radical , the king pin inclination is around 15 degrees .For strength purposes , not an option for me .
3-6.5 " is the upper control arm length
so I can pick the angle of the upper arm and the amount of anti squat and type of shock and spring rate .Not liking the idea of picking a setup and being stuck with it , I am planning a setup that will be adjustable as to arm angle , camber and anti squat .I have a couple of designs in mind , just no time to do anything for a couple of days .I have a coilover ty wrapped at ride height and it looks like it can be mounted to the spindle adaptor and angled back to a mount on the shock tower .
Lunatic FEB 17, 05:34 AM
I see what you're trying to do. Now, if using an 88 upright be more beneficial for your application, I have a spare set if needed. Looking at the these two photo's, from Dave's build, (I hope he doesn't mind), one can see the advantage of using spherical joints to make the upper ball joint unnecessary. Thus providing greater travel (without binding) in the spherical joint's design properties. The mounting points of the rod ends could be placed in a variety of locations making mounting easier. Just adding another option to your design.
wftb FEB 17, 02:33 PM
I have thought about using the 88 spindles but for now I am going to see if the direction I am going pans out .It is looking really promising right now , I am really getting enthused about the project and the only thing slowing me down is work and the freezing weather .That being said , I am always interested in other directions and a set of 88 spindles would be nice to play with .I could trade you the strut coilover kits I won't be using if you want .I can take the other side off any time now .Thanks for the reply .
wftb FEB 18, 06:14 PM
With the stub locked in place , I needed to find the angle that the inner bushings of the lower control arm run at .So I tacked together a frame work of 2 verticles spaced the same distance from the cradle where the lower arms mount and got the angle I needed up near where the upper arms will be mounted :
By a minor stroke of luck , the front edge of the plate that is part of the frame rail reinforcing is on the angle that the upper arm needs to be at .This will make everything really easy to square up for mounting the arm .
Lunatic FEB 18, 08:25 PM
It appears as though you've finalized a way to mount the upper control arm to the Fiero upright. If not, I quickly drew up a little bracket that you could easily replicate for your project. (I used 1/4" for my design). It bolts over top of the upright and there's a hole in the top that would allow for the upper ball joint. (Provided one used a tapered reamer to make the hole). You could also angle the top of the bracket so that the ball joint will be in the middle of the stroke when the car is level. That should give you all the movement that you're looking for without binding on compression or rebound.





[This message has been edited by Lunatic (edited 02-18-2015).]