One of the suspension/handling upgrades for my 88 Fiero is to replace the poly bushing lateral links with some rod end lateral links. This will eliminate any lateral deflection and provide a more consistent toe setting (important for good tire wear for the width of tires I plan to run). Several vendors already sell this upgrade, but I wanted to see if I could build a set using available off the shelf components (no custom spacers required).
The key to this conversion is the QA1 rod end that essentially has a built in spacer shaft. This is a teflon lined, chromoly, rod end that is rated for 24,000 lbs. The hole is 1/2" and it nearly fills the length of the mounting pocket on the cradle.
A test fit showed that finding a couple of washers the proper thickness could close up the gap quite well. In this pic, the washers are the washers from the lateral link bolts, but they are slightly too thin.
To put the lateral link assemblies together, you need the rod ends, swaged tubes, 5/8" jam nuts, and some spacers to close the gaps in the mounting pockets on the cradle.
Due to manufacturing tolerances, you may need to slightly widen the lateral link pocket. I used a wheel bearing bolt and 2 nuts. Thread the bolt into the nuts and install the closed end of the wrench as shown. Once the nut it tight to the head end of the bolt, tighten the other one to push the wall out slightly:
Then install the links with the thick washers on both sides:
The rear pocket is a little short to allow the rod end to stand up. You could use a pry bar to push the top of the pocket up, or just leave the rod end at an angle:
The links mount to the upright with thick washers on both sides of the rod ends:
Here is a list of part #'s, quantities and prices:
The QA1 rod ends and Afco tubes were purchased from Summit Racing - it did take about 1 month for the QA1 rod ends to arrive (they were back ordered at the time). The rest of the nuts/bolts/washers came from McMasterCarr.
As you can see this project will set you back about $205 + shipping which is less than most vendors are charging for this upgrade. You might be able to save some $$ on the jam nuts and spacers, but I wanted the nuts grade 5 and zinc coated and a single thick washer on both sides.
I am sure these components are not DOT approved, so this should be considered for off-road use only (and no, I will not be selling these kits).
[This message has been edited by fieroguru (edited 06-22-2013).]
darkhorizon and i were just talking about this. i have the heims and it makes a very nice improvement to the feel of the suspension, but what do you expect the life to be? i will not use them anymore on the street just because they wear out so quickly. maybe 5000 miles or so. maybe i just cheaped out on quality ends? (maybe i am just cheaping out now?) do you have boots for yours? those helped some. (thanks for the part numbers!)
[This message has been edited by ricreatr (edited 01-30-2012).]
I have the heims and it makes a very nice improvement to the feel of the suspension...
As someone with experience then, can you comment on ride noise, vibration, harshness? On an '88 chassis, if you do this mod there is nothing between the road and the cabin to absorb any NVH. Seems to me this would be fine for those wanting to trade off some comfort for all out handling, but maybe not for everyone. What are your impressions?
As someone with experience then, can you comment on ride noise, vibration, harshness? On an '88 chassis, if you do this mod there is nothing between the road and the cabin to absorb any NVH. Seems to me this would be fine for those wanting to trade off some comfort for all out handling, but maybe not for everyone. What are your impressions?
Since this is just the lateral links there shouldn't be much if any change in NVH while driving in a straight line. If the NVH is too much to handle just reduce the steering input
darkhorizon and i were just talking about this. i have the heims and it makes a very nice improvement to the feel of the suspension, but what do you expect the life to be? i will not use them anymore on the street just because they wear out so quickly. maybe 5000 miles or so. maybe i just cheaped out on quality ends? (maybe i am just cheaping out now?) do you have boots for yours? those helped some. (thanks for the part numbers!)
The teflon lined rod ends are supposed to be good for 2-3 years... probably all depends on what conditions you drive them in. I do not think the seals would work on the extended sleeve portion, but who knows. Might be able to use some poly ball joint/tie rod sleeves to seal up the area.
Since this is just the lateral links there shouldn't be much if any change in NVH while driving in a straight line.
Perhaps, but I believe that some of the engine/transmission vibrations would be transferred from the axle shafts to the hub bearing, hub, lateral links, cradle, and then to the chassis.
Man... where was this last year. I spent over $600 buying the HT Motorsports set up. I do like what I got, but it would seem that I could have dont it cheaper this way. Oh, well, thats why we all follow the "guru" threads so we can learn how to do this stuff to our cars.
I would be curious to see your parts list and total cost for the conversion.
I have about $250 in it as well, the swagged tubes were $18 each x6 My rodends are teflon some 1/2" some 5/8" at $14 each x12 spacers were $2 each x24 I used all grade 8 bolts which needed only a slight reaming thru the holes to fit All from smileys racing
I definately like this idea. Makes me wonder if I could reduce my width in the rear a little to be able to fit a wider wheel back there. Maybe use different axles to accomplish another inch or onch and a half of fender clearance.
I definately like this idea. Makes me wonder if I could reduce my width in the rear a little to be able to fit a wider wheel back there. Maybe use different axles to accomplish another inch or onch and a half of fender clearance.
can you comment on ride noise, vibration, harshness? ?
blooze, it has been a while, and of course my comparison was to worn rubber bushings, but i noticed the rear tracked much better in corners and under accel (about 250hp). i did not notice any harshness from the modification at all. i have 17" wheels and 45 series tires.
we need to convince guru to apply these all these mods to a mule fiero one at a time, to give experience with each one!!! (ill do the wrenching!)
And probably a few more before it is done... Unfortunately, all these are happening together, so it will be difficult to speak to the benefit of each individual upgrade.
Awesome write up. Its going on my to-do list. I thought all the stock lateral links were the same length, but I see that you have two 8 inch and two 9 inch. Am I wrong about that, are the rear stock links longer?
Yes, they're different lengths. The rear link measures 324 mm (plus or minus) eye-to-eye, and the front adjustable link measures 297 mm (plus or minus) eye-to-eye.
The key to this conversion is the QA1 rod end that essentially has a built in spacer shaft. This is a teflon lined, chromoly, rod end that is rated for 24,000 lbs. The hole is 1/2" and it nearly fills the length of the mounting pocket on the cradle.
A test fit showed that finding a couple of washers the proper thickness could close up the gap quite well. In this pic, the washers are the washers from the lateral link bolts, but they are slightly too thin.
I built rod-end links for my Formula, but I didn't know about these parts. I used 5/8" rod ends and had to turn shouldered spacers that would both fit the rod ends into the pockets on the cradle as well as adapt them down to the 12mm pivot bolts. Obviously that's a lot more labor intensive than this way.
I'm curious to know what the service life of "unbooted" rod ends is. I have Pro-Werks boots on my rod ends, but they won't work on the ones you found.
As someone with experience then, can you comment on ride noise, vibration, harshness? On an '88 chassis, if you do this mod there is nothing between the road and the cabin to absorb any NVH. Seems to me this would be fine for those wanting to trade off some comfort for all out handling, but maybe not for everyone. What are your impressions?
Very small increase in NVH, if any at all. Most of the compliance of the car's ride comes from the trailing arm bushings. The stock rubber bushings in the lateral links obviously don't give much cushion, while the stock trailing arm bushings are much larger.
I'm curious to know what the service life of "unbooted" rod ends is. I have Pro-Werks boots on my rod ends, but they won't work on the ones you found.
I am curious too. I might just leave them exposed to the elements to see how long they last. If the last 2 years before needing replacement, then I will probably just leave them exposed going forward. I could probably cut down some poly tie rod end cups and use them as seals, but not sure if it is worth the effort. This car will be a fair weather only car, but it will sit outside year round.
Could you tell me how wide your rod ends are? I'm looking at doing a similar setup with different components and want to know if these will fit with a couple washers like yours do. Thanks
Could you tell me how wide your rod ends are? I'm looking at doing a similar setup with different components and want to know if these will fit with a couple washers like yours do. Thanks
The inside target width for the cradle mount pocket is 1.60". The rod ends I used are 1.25" wide.
I already looked there and didn't find "rod end spacers".
Jegs sells some. They have then with a 1/2" ID and an overall length of 1/4" and 1/2"... but not sure how difficult it would be to find a rod end about .600" wide. As I looked into my solution, I didn't want to have to pull the mount box inward (making it difficult to return to the stock lateral links). http://www.jegs.com/i/JEGS+...s/555/64201/10002/-1
Ballisticfabrication.com has good stuff too. The setup I'm thinking of doing will use a 5/8" rod end with two 5/8" to 1/2" high misalignment spacers. The width of the rod end with the two spacers is 1.5". I'm thinking I should be able to shim it to fit with one or two thin washers. Then I plan to get a 5/8" tube adapter to weld in to make my own links.
[minor rant] Since you know what you bought, I figured it would be a lot easier for you to spend 30 seconds on the site to find your part... You could also type up the part number from your invoice...
I can imagine how the conversation would go if I called them and said "This guy on the internet said I should call you about rod end spacers, but I don't know what they look like and don't have a part number."
I've done my share of part number posting on this forum... it's not hard. [/minor rant]
quote
Originally posted by fieroguru:
Jegs sells some. They have then with a 1/2" ID and an overall length of 1/4" and 1/2"... but not sure how difficult it would be to find a rod end about .600" wide. As I looked into my solution, I didn't want to have to pull the mount box inward (making it difficult to return to the stock lateral links). http://www.jegs.com/i/JEGS+...s/555/64201/10002/-1
McMaster 60745K261 shows a 1/2" rod end that's 5/8" across the flats... but I don't think I'd want to use a joint that small in this application. Although the 1/2" rod end is only rated 10% lower than the 5/8"...
Also, a big part of the need for spacers is for concentricity of bigger rod ends around smaller bolts... I have 5/8" rod ends and 12mm bolts, but the spacers I made keep the rod ends centered on the bolts. Any off-the-shelf spacer would have to do something similar.
[This message has been edited by Will (edited 02-03-2012).]
Also, a big part of the need for spacers is for concentricity of bigger rod ends around smaller bolts... I have 5/8" rod ends and 12mm bolts, but the spacers I made keep the rod ends centered on the bolts. Any off-the-shelf spacer would have to do something similar.
That's the main reason I stuck with the 1/2" rod ends (thread size on the end is 5/8-18 but the hole in the ball is 1/2"). I could have machined the needed spacers/shims for a larger rod end, but wanted to keep it simple enough that the combo could be replicated by others.
I am keeping rubber bushings in the trailing link, that is the key to a near stock ride, but improved lateral control.
That was my plan as well, but I ended up replacing the trailing link bushings with poly. Honestly, I couldn't tell any difference in harshness or noise. It does make the car easier to control when the back end starts to come around, tho (auto-crossing).
[This message has been edited by sspeedstreet (edited 02-03-2012).]
I'm curious, fieroguru, if the "high misalignment" feature of those rod ends was a consideration you made in choosing them. I ask, because I was playing with some rod ends earlier today (non-high-misalignment), and they have a fairly high range of motion in them (around 30 degrees). I would think that's plenty for the rear suspension. Or did you recommend them only because of the built-in spacer?