Mustang II chronicles, failure abounds

Here is what Im talking about shaving down probably 3/16''

 

I would trim down the crossmember bushing in this case. He is correct in the control arms shrinking when they weld them, they should however take that into account when they designed the fixtures. If your attachment bolt slides through the bushings as they are, spreading them will put one or both slightly out of alignment and will cause premature wear on those tiny bushings.

Carry on!

 

So triming the inner tube down will not give me any alignment or geometry issues?

Thanks.

No more hei@@s products for me!!!!

 

Wow! 5 pages and over 90 post about a completely non-traditional modification. What's the H.A.M.B. coming to?

Bob

 

Check and see if the bolt will pass all the way through the arms.

 

Yes, Im using the same bolt that is supplied with the arm

 

Greatthread and info here for all... just one thing I want to add for folks... when welding, becareful when you approach the end of a joint and material... when wrapping an edge becareful your not actually weaking the joing when wrapping the material, as this will be a area prone to cracking due to the thinning, undercutting of that edge. Sometimes its best to stop 1/8" short of the end of the material. Hard to explain, wish I had pics... do you El Polacko?

 

I've only seen what you are describing on automated or assembly line weldments and have considered them a mistake. I have always fully welded tabs and wrapped the ends.

In fact I have seen more weld cracks or failures from incomplete welds than due to undercutting. It really depends on how the tab is designed to be used and fitted.

 

If this is something that has been on the road and you are not seeing any cracks forming, chances are things are sound. However! Powdercoating can hide small cracks in the foundation.

Outside of stripping the frame there really is no sound way to tell if you have cracks forming. I do highly suggest adding the brace from the rear of the lower control arm to the frame. It can be bolted on, heck there are steel "nut serts" that can be installed that would be up to the task.

 

Thank you, I took a look at your work, nice stuff, I sure am glad to be able to get some insight from you. I'm off to making a bolt on unit based upon your example. Before I commit by making any holes I will show them to you and see what you think. I'll post them for the forum and see if any flaws can be spotted.

 

Researching like a mad man now, Too little too late maybe. Found some info regarding the bolts being grade 5. This would be the bolt that is the focal point for all of the load spreading duties being absorbed by the attachment. Various opinions have been bantered about regarding it's composition, I am leaning towards grade 8, others have cited shear issues and tensile strength arguments. What would your preference be?

 

The grade 5 bolt being superior to grade 8 for suspensions is one of those wives tales that just keeps getting promoted as truth.

Something about the 5 yielding or bending before failure and an 8 would just snap. Pure crap, grade 8 bolts are superior for suspension components. Almost every OEM I have put my eyeballs on have had Grade 8 or higher on all the suspension attachment points.

Check this out, he explains if very well: http://www.rockcrawler.com/techreports/fasteners/index.asp

 

Something about the 5 yielding or bending before failure and an 8 would just snap. Pure crap! Sounds like a crooked politician speak. won't raise taxes but gives away money at record pace.
Bolts are graded 8 because they can meet grade 8 standards, grade 5 bolts can't. tt

 

Elpolacko, are Mustang II strut rods bar stock or tube stock?

I found some on the net listed as tube stock, so I'm wondering.

Thanks for any help, this has been an interesting thread and made me realise i need an upgrade in my strut mounting system.

 

Stock struts are forged solids. Threaded for shoulder joint style bushings.

Aftermarket stuff is almost always tube. Four bar sleeve end should be concentric with the control arm bushing.

 

Thanks, if you look at post 62 on page 2 of this thread you will see what I've found, you stated there that they looked fine to you.
Presently have the type that basically attach at end of pivot bolt, which you've stated are not good, and when i think about it it makes sense to me as well that, that type doesn't offer much rigidity to forces on control arm.

Concentric? not just parallel? Is that possible wouldn't the pivot point or axis of both control arm and strut rod then need to be the same?

 

OK. Lots of great info on this thread. I appreciate it in it's entirety. I too, have a question. I have a customer with a 61 unibody ford. THe suspension if rom Full tilt engineering in Grand junciotn CO. Not a bad kit from what I have seen. As stated, the problem isn't always the kit, but the installation. Seems what I have in front of me. In this case, when the vehicle is on the ground, the lower control arm travels upwards from the crossmember the the spindle. The vehicle is also too responsive to bumps in the road. When it hits one, it jerks all over. The tie rods from the rack and pinion, also angle upward. Now from my understanding, the lower arms should be level under vehicle weight? So should the tie rod ends? Is that right? The only time it should be at that agle it cornering or bumps in the road right?

 

These guys? http://www.fulltiltstreetrods.com/frontsusp.htm

Sorry, I had to break up your paragraph. Makes it easier for me to follow along.

First off, I'm not a fan of putting the MII on anything like the F100. The track width had to have bee widened to make it fit. The Roll center is reasonably low on a stock MII, widening it will make it lower and more prone to body roll.

What many manufacturers of these kits do to mask the problem, either indecently or coincidentally is to spread the upper and lower attachment points. If they did it on purpose, it was to lengthen the instant center of the control arms to slow to slow camber gain and raise the roll center. If they did it for rack and pinion clearance (most likely) they basically get the same result.

The downside is the altered camber curve. Most of the time if the increase is in attachment point distance is minimal, the slight loss is not going to greatly affect the drive. If they really increased the height the camber curve is lost and drive is inconsistent.

Couple that with a suspension bottomed out, the instant center would not go to the opposite side of the car but outside the same side further dropping the roll center subterranean.

I did a post http://www.jalopyjournal.com/forum/showthread.php?t=70073 that gives you all the stock dimensions for stock Ford MII geometry.

For this situation, the higher the better if you want it to handle better.

But let's get to the meat of the situation. What you are describing is a sacked out suspension. The control arms should be lower at the ball joint end in reference to the crossmember. This means of course replacing the coil springs with taller or stiffer units. This will raise your ride height and you may need to compensate with a dropped spindle if you want to retain your current ride height. If the suspension is bottomed out and you have no usable travel it could cause this.

Alternatively, with the suspension in this sacked out position you get a pretty high amount of camber change under compression. High negative camber causes a fairly hard on-center feel because of the way it is loading the tire and effects the scrub radius.

I also suggest is to pull the springs out entirely and cycle the suspension to check for bump steer. Depending on how they widened the front suspension track to fit this truck determines if you have bumpsteer or not. Typically the MII would need to be widened 4" to get close to the 61" track the truck had originally. Some companies did use longer control arms and longer tie rod ends to achieve this. Others would screw on a 4" extension to the passenger side, others would add 2" to both ends of the rack. All of those are valid but all have draw backs, wear, complexity etc..

If the rack has been lowered out of position and the tie rod is not close to parallel to the lower control arm, it will also cause this.

If you can shoot some pictures and post them, I would be willing to give them a look.

 

Yea, who doesnt want nice shiny new chinese re-pops of pinto parts under thier car?? All the bubble-pak billies around here are trying to talk me into putting this shit (not a swear word,acronym for "super hot interesting tech") under my off-topic '60s ride. NFL!

 

I thought that looked wrong. I will do my best to get some pix. He had some other work fixed by me on the same vehicle, and had aleardy taken it home to enjoy it for the remainder of the summer.

From the explanation given, the crossmember was wider to provide the correct track width you are speaking of. The rack does have extensions but looks like it sits to low as well. If i read what you typed correctly, the rack should be level to the lower arms? Correct? If so, I have a bit to fix from what I recollect. Thanks for the assistance. I unfortuanately have not been able to take chassis/suspension classes and am soaking up all I can. I appreciate it.

And BTW, how did you drop your truck? I am doing my 63 f100 soon. So I am curious

 

Parallel, not level on the tie rods and rack.

I have dimensions on that thread I refereed to. It should put the centeline of the rack above the lower control arm pivot bolt by 2".

You should be able to squeeze the bellows covering the inner knuckle of the tie rod. Try this trick, tie a string or use a piece of thin masking tape to connect the upper control arm pivot to the lower control arm pivot. That inner knuckle should land dead center on that string or tape.

One of the more common mistakes we have seen in set up is not getting the rack centered properly before alignment. You should have equal turns from center to lock in both directions. If it's not centered, those inner knuckles are out of alignment and the front suspension will bumpsteer while traveling straight down the road.

My truck has one of my former products on it. Based on 1987-1996 Dodge Dakota pickups. I have a custom set of tubular control arms and 2" dropped spindles, uncut coils, Bilstien shocks and I Z-ed my frame 2.5". When my partner and I split, he took possesion of the crossmemer kits. Someday he will produce them, I just don't know when.

http://s206.photobucket.com/albums/bb93/ELpolacko/My 63 Ford F100/

 

what year dajota? I have that front end is why I ask. Is it all new contolarms? Or how do you have it? If you do not mind me asking that is? More pix of it maybe? If that is cool.

 

If they are concentric, wouldn't that mean a straight piece of stock could pass thru control arm sleeves and strut rod mount both.Is that what you mean? I'd like to know the answer to that one before i screw things up.

 

You must have missed it in text just above the picture:

The control arms are custom, by me, for me. I made about 6 sets of these total. I do not have the jigs to build more. If I did, they would have to be custom made and expensive. Sorry. You can use the stock Dakota arms, there is nothing wrong with them.

I also included a link to my photobucket album for my truck. It has just about every picture I have take in it.

 

Yes, that is correct. If the bushings on the same arm were not concentric there would be considerable bind as the arm moves through it's range of travel.

 

Thanks, that clears that up then.
By the way where are you located?
If i ever get near your area i could use one of those front opening stude hoods that's caused so much goings on over on the SDC site.

 

Shit! Sorry bout that! MY fault. I should pay better attention.

 

Pretty much in the Northwest corner of I-10 and I-17. If you go to my website I have Bing and Google maps detailing it.

Gawd, ain't that the truth. That Tom character is a tad sensitive.

No problem man. We all miss it sometimes.

 

Say are there any make of tubular lower A arms you would recommend?

 

I shy away from making recommendations. There aren't any out there I can promote.