Rear Suspension for street application

[HRpartsNstuff]

I could be wrong, but your reply seemed to be trying to tear my post apart. Crazy thing was, I was actually agreeing with several points you made on an earlier post & trying to help the others that seemed confused on the whole issue. If you still disagree with something I have posted on this thread, I guess I can post details & proof to back it up if need be. I have devoted the last 12+ years to suspension development for street/strip cars, and have close to 100 years combined racing/suspension design & tuning experience including my friend & tech person Dave (answers phone line) & my brothers, that help in the design & testing process. I sure don't claim to know it all, but I make every attempt I can to know any info I pass on to be true & backed by facts or proven testing etc. If I hear the same thing 50 times from racers supporting something, I usually pass that on as coming from customer feedback or however I got the info. I don't just take 1 or 2 persons opinion & tell the world that's the way it is.

It's not the size of the bushing that tears up the mounting points. It's the fact that they're bushings and can't twist when the rear end articulates. There is no good bushing.

I just mentioned "small" mainly so people might realize the ones I was referring to. BUT, if they would have used a nylon bushing with a 1/2" cross section vs an 1/8" cross section, it would have let the bushing deform a little and take some bind out of it. That is a minor issue, but has been tested & proven. We are coming out with a new & improved Delrin upgrade for our arms that will work great on street/strip cars down into the 8's. For you to make a general statement that "there is no good bushing" is not a true statement. We have customers running mid 8's on our "old" delrin bushing design, and they work just fine. There are many out there that are NOT fine, so I can see where you could get that idea from.

You say adj uppers don't have any effect on instant center. Of course not. The adjustability of the bar has nothing to do with this. It's the angle of the bar or susspension geometry that changes this.

I just pointed out that adjusting the uppers didn't have any NOTICEABLE effect, for those that were confused in this thread as to the questions of what does what. Technically speaking, shortening the uppers (leaving everything else the same) DOES make a VERY slight difference, but didn't want to confuse the issue. Making a BIG pinion angle change by shortening the uppers only will pull the upper monting point on the rearend toward the other end of the arm. Only thing is, it doesn't pull it exactly straight thru the same instant center lines it had. As it shortens, it pivots/rotates the rearend off of the lower rear mounting point in an arc. If it moved in a straight line (in relationship with all mounting points), then the distance between the upper & lower mounts on the rearend would have to increase, which is impossible without moving the brackets. This is a VERY small amount & shouldn't really be considered for 99% of people out there, but it does effect the instant center (technically speaking). That was another reason we made 1/4" longer lowers, so you didn't have to shorten the uppers so far to get desired pinion angle.

You say spherical rod ends ride rough. This statement couldn't be more wrong.This is a silky smooth ball and socket joint. The ones I use are teflon lined. My care has never had a nicer ride.

This is just 100% of the feedback we get from our customers & what I see from others racing faster cars. It's not a huge issue for most of them, since true 8 and 9 sec cars usually don't go on very long trips & can be tolerated to a degree. It's not the MOVEMENT of the ball & socket that effect the ride quality, it's the lack of some material that can absorb vibrations and to reduce any shock transmitted from the road to the chassis (like rubber or poly). Being that you have teflon lining, that will help slightly to improve ride over non-lined rod ends, BUT as they wear out you will start to feel & hear a lot more than the non-lined ones would be (at same use level). You won't find the teflon in many super fast cars.

You say round is weaker than rectangle,yet every prostock car on the planet uses round.

I said round tube has weaker connections on the ENDS, because there is less area of contact to weld. As I said about the different GRADES of steel, I can buy stronger rectangle than round, and I can buy stronger round than rectangle. It all depends on the type of steel, what grade it is, and the process it was made with, and any process after it was made. Pro-Stock cars use round because they use top grade chromoly tubing that isn't available in rectangle shape, and weight is a critical issue with them.

You talk about the tubes being pulled off the U brackets. When you move the upper arms mounting points to the axle upward with the setup I use you don't have a U bracket.

That is definitely one type of "no-hop" bar that raise the upper mounting point, and you have 1 less "issue" to worry about back there then. I was referring to the more common setup that most upper adjustable arms look like, as pictured in topher455's post towards the end of pg 1.

There's no way that Burger King will ever say that Wendy's sells a good product. That's why I would never ask there advice about Wendy's products. When someone asks you for advice on susspensions you'll always say your products do it better because you sell them. It's not wise to take advice from someone who might stand to profit from you taking it.

In most cases you would be correct on that. BUT, as most that know me would agree, I post info here to HELP people out & answer questions. I am not taking the time to type all this to hopefully sell a suspension kit to someone out there reading it. One of the reasons this board has done so well over the years is that the average (new or old) car nut can benefit from other racers and manufacturers knowledge and experience. That is all I was trying to do here, whether you believe it or not is not an issue for me. We get most of our sales from our own customers passing on their experience to others.

Untill you sell an upper bar with a relocated mounting point at the axle, your bar does very little (in and of itself )to improve traction and is ineffective at preloading the susspension.

We sell upper control arms to reduce the flexing of the flimsy stock arms, and provide a greatly improved bushing, and on the adj ones, the ability to set pinion angle, along with big increase in strength & safety & appearance. We have seen cars get more traction & drop 2-3 tenths by getting the pinion angle set correctly on a faster car. We have seen stock & cheaper uppers tear apart & almost wreck the car & kill the driver. If you call that "very little" then so be it, we all got opinions.

The reason you sell a fat sway bar is because your arms can't be adjusted to preload the susspension. With the setup I've described you don't need a swaybar/bandage.

The swaybar is NOT a bandage at all, not sure where you got that idea from. Using airbags to preload the pass side is a Band-Aid approach, and worked decent when that was all that was available. Last I knew, the Dick Miller setup you described uses an anti-roll setup that goes up into the trunk area. That (and my swaybar/anti-roll system and most others) are what keeps the car level & going straight. You can only do so much with the control arms to prevent body roll during a hard launch. I am not saying that to try & sell you anything, since I see that probably isn't possible & not my concern. You can look at ANY fast car out there running a 10.5 tire, and you will find some sort of system on it to control the body roll and/or torque effects (over & above upper & lower arms).

I am a racer at heart & will support other racers as much as I can. I started my company off of friends & racers that saw what I was doing with my own "homemade" parts & they wanted me to make them a set. I can get just about ANY product currently made or available and offer it as my own (private label) or under their name. After looking at the many different designs out there over the years, we came up with our own design that gave even more benefits without all the shortcomings & negative side effects that many of the others had. Then made it with top quality materials & components with top notch craftsmanship.

I have seen & heard what works & what doesn't, and done 100's of tests to confirm it too. We make stuff that works as advertised, and so far 100% of our customers can confirm this. We make & sell parts to help racers go faster & safer & improve their car's overall appearance & performance, and stand behind every one of them. We do it for the love of racing & the racers, not to get rich. We could always make 1000's of Mustang parts with cheaper materials & parts, and make other parts that don't really work but still sell good, and get rich like many other "big name" companies out there, but we choose not to. We sell our products because we know every customer will be extremely satisfied with the parts, the craftsmanship, and the performance & safety they provide, along with the detailed instructions & easy installation & support before/during/and after their purchase. I personally enjoy going to the events & seeing the happy customer & hearing how our parts helped them out, and knowing they have a better chance at winning & not getting hurt. Soooo, I would really appreciate it if you could refrain from telling me (and everyone reading this) the reason you "THINK" I sell any of my products.

PS- For those installing the big solid swaybars in the stock location (onto the lower control arms) and having to "beat" them into position, here is some feedback that we have seen & heard:

The additional pressure that the bar has pushing the control arms apart will eventually tear up the bushings in the control arms. Of course I could give the "Wendy's" answer & say that you just need our setup, but I just wanted to point out that you should grind some material off the mounting surfaces until it goes in with little effort. This isn't easy or quick to do, but not doing it will eventually tear up the bushings for sure. The flange on the side of the bushings gets cut/ripped off & then things start to move around under power & the car can get real loose.

 

[Ttype6]

Sounds good, 1 3/8 sway bar here I come.

As far as all the other discussions in this thread, I dunno what to think anymore. I really don't see how dropping the LCA mount an inch or two is going to "severely bind" the suspension. The control arm can still move... it's still in the same spot... just at a slightly different angle. Instant center is fundamental to a good launch so I would think it's something worth adjusting.

As I said in my earlier post,it's not the relocation of the lower bar that creates the bind. It's the use of a bushing. A bushing can only pivot. It can't twist. It needs to twist when the axle articulates. The only way to adjust instant center is to change the angles of the upper or lower bars. Moving the point where the uppers connect to the axle upward is the only and right way to do this. Until you do this you can't preload the passenger side to create equal downforce to each rear tire,which is how you get the car to leave straight without twisting.

 

[Ttype6]

I could be wrong, but your reply seemed to be trying to tear my post apart. Crazy thing was, I was actually agreeing with several points you made on an earlier post & trying to help the others that seemed confused on the whole issue. If you still disagree with something I have posted on this thread, I guess I can post details & proof to back it up if need be. I have devoted the last 12+ years to suspension development for street/strip cars, and have close to 100 years combined racing/suspension design & tuning experience including my friend & tech person Dave (answers phone line) & my brothers, that help in the design & testing process. I sure don't claim to know it all, but I make every attempt I can to know any info I pass on to be true & backed by facts or proven testing etc. If I hear the same thing 50 times from racers supporting something, I usually pass that on as coming from customer feedback or however I got the info. I don't just take 1 or 2 persons opinion & tell the world that's the way it is.



PS- For those installing the big solid swaybars in the stock location (onto the lower control arms) and having to "beat" them into position, here is some feedback that we have seen & heard:

The additional pressure that the bar has pushing the control arms apart will eventually tear up the bushings in the control arms. Of course I could give the "Wendy's" answer & say that you just need our setup, but I just wanted to point out that you should grind some material off the mounting surfaces until it goes in with little effort. This isn't easy or quick to do, but not doing it will eventually tear up the bushings for sure. The flange on the side of the bushings gets cut/ripped off & then things start to move around under power & the car can get real loose.

There where several statements in your post that where wrong. Can you prove that a bushing not only pivots,but twists when the axle articulates? Can you prove that the passenger side susspension can be preloaded using upper control arms that use the stock mounting points? The bar that Dick Miller sells is for 8 second cars.

 

[Ttype6]

Paul has a excellent product, and has spent years testing what works and what doesn't. Your bars that you are showing there with heim joints will not last under street conditions period. They will become worn and noisy once the dirt sets in within months.

As I stated in my earlier post,The rod ends I use are coated with Teflon. Because of this I don't grease them. It's the grease that attracts the dirt. I've had this setup for 6 years and it's still silky smooooth. When do you think they will elongate and rattle? How does this disprove my statement that bushings pivot but don't twist when the axle articulates? How does this disprove my statement that upper control arms mounted in the stock mounting points don't allow you to preload the passenger side? How does this disprove my statement that my setup allows me to preload the passenger side and because of this I don't need or use a sway bar?

 

[BlackMetal]

As I said in my earlier post,it's not the relocation of the lower bar that creates the bind. It's the use of a bushing. A bushing can only pivot. It can't twist. It needs to twist when the axle articulates. The only way to adjust instant center is to change the angles of the upper or lower bars. Moving the point where the uppers connect to the axle upward is the only and right way to do this. Until you do this you can't preload the passenger side to create equal downforce to each rear tire,which is how you get the car to leave straight without twisting.

Okay I see what you're saying. But my point that I made earlier in this discussion is... won't the control arm in it's stock location bind anyway then? If the bushing is the problem and not the location of the control arm, then it really shouldn't matter whether or not I decided to mess with these LCA relocation brackets.

 

[Ttype6]

Okay I see what you're saying. But my point that I made earlier in this discussion is... won't the control arm in it's stock location bind anyway then? If the bushing is the problem and not the location of the control arm, then it really shouldn't matter whether or not I decided to mess with these LCA relocation brackets.

I'd use the arms you have with the relocation brackets. At least you'll be doing something that creates downforce on the rear tires. This set-up won't allow you to preload the passenger side so the car will twist when you launch. You'll need the sway bar to minimize this. It will be very effective. If you want to leave with alot of boost on the street you'll need to add weight to your trunk or fill your gas tank. There's just not enough traction on the street without doing this and this is too easy to try ,to not try it.

 

[topher455]

I have read the above posts with interest regarding the rod end debate. We all know that any type of bushing will bind to a certain degree. Rubber bushings being softer than polyeurethane will allow more movement because the rubber will flex. I think we all can agree on that. That is why I chose the rod end type suspension shown in the above pictures. These ends may translate noise through the chassis but the body bushings are there to absorb chassis noise and vibration before it makes it to the body/cabin area. I am afraid I dont understand 2 things

1) How will delrin bushings articulate like a rod end? I understand the center will rotate freely but zero lateral movement will be permitted.

2) How will it be quieter than a rod end with a nylon insert? That is basically what a delrin bushing is correct? Hardened nylon bushings with a greased steel sleve in the center. ( I have delrin bushings on my Global west front uca's)

Im not trying to cause argument here. These are the considerations I made (as well as others) when selecting my suspension system for my car. The car will pretty much be my daily driver/fair weather car. Powertrain is a 5.3 liter
truck motor with T-70 turbo and T-56 manual trans and megasquirt injection.
I just thought I'd give all the details since I'd appreciate some veteran advice on my suspension setup. This is the first G- Body suspension Ive setup that will be putting manual trans turbocharged V-8 power on the rear suspension so I wanted to go a tad overkill. I also added a crossmember that ties into the upper mounting points and the Hotchkis braces as well as going over the factory welds in some places. Input is welcome.

BTW Hope Im not thread jacking Turbo6Chicago. Its rare to get so much knowledge in one place so Im trying to take advantage.

 

[Ttype6]

I have read the above posts with interest regarding the rod end debate. We all know that any type of bushing will bind to a certain degree. Rubber bushings being softer than polyeurethane will allow more movement because the rubber will flex. I think we all can agree on that. That is why I chose the rod end type suspension shown in the above pictures. These ends may translate noise through the chassis but the body bushings are there to absorb chassis noise and vibration before it makes it to the body/cabin area. I am afraid I dont understand 2 things

1) How will delrin bushings articulate like a rod end? I understand the center will rotate freely but zero lateral movement will be permitted.

2) How will it be quieter than a rod end with a nylon insert? That is basically what a delrin bushing is correct? Hardened nylon bushings with a greased steel sleve in the center. ( I have delrin bushings on my Global west front uca's)

Im not trying to cause argument here. These are the considerations I made (as well as others) when selecting my suspension system for my car. The car will pretty much be my daily driver/fair weather car. Powertrain is a 5.3 liter
truck motor with T-70 turbo and T-56 manual trans and megasquirt injection.
I just thought I'd give all the details since I'd appreciate some veteran advice on my suspension setup. This is the first G- Body suspension Ive setup that will be putting manual trans turbocharged V-8 power on the rear suspension so I wanted to go a tad overkill. I also added a crossmember that ties into the upper mounting points and the Hotchkis braces as well as going over the factory welds in some places. Input is welcome.

BTW Hope Im not thread jacking Turbo6Chicago. Its rare to get so much knowledge in one place so Im trying to take advantage.

Everything you say here is true and makes sense,But the facts don't stop people from arguing or defending a position. I like the undeniable facts you stated and all the questions you asked.

 

[HRpartsNstuff]

There where several statements in your post that where wrong. Can you prove that a bushing not only pivots,but twists when the axle articulates? Can you prove that the passenger side susspension can be preloaded using upper control arms that use the stock mounting points? The bar that Dick Miller sells is for 8 second cars.

I think we all need to take a deep breath & relax
Most of what's posted here by all is actually agreeing on the same PRINCIPAL, but some is getting lost in the DETAILS.

Let's say we could do a test, mounting the lower control arm in the chassis, and using a prybar in the opposite end (that would have bolted to lower rearend brackets):

With a stock rubber bushing in the arms, you can easliy rotate it up/down side-to-side etc. This actually has the least amount of bind (of a bushing type). Only problem is, they basically collapse front to back when power is applied, not strong enough.

With most other aftermarket arms with poly bushings, some could move a little side to side & twist, some won't budge at all, just depends on design & parts used. Some have so much pre-load on inner sleeve pressed into the poly that they are even stuff moving in the "normal" up & down motion. Ours have a decent compromise & let it articulate a little bit & move fairly easily, but stiff enough to handle the power down to mid-low 1.4 sixty ft times or so.

The SSM style "delrin" bushing or teflon or any other type that is a thin wall sleeve over the inner steel sleeve will not allow any articulation (like you are thinking). These will definitely bind up. Also, they will "hit" the chassis hard on faster cars that it is VERY VERY common to see bolt holes elongate and brackets to break off.

Our "delrin" bushing upgrade we have been selling for a couple years articulates decent like our regular poly, but is much more solid front to back for faster cars & down to 1.2 sixty ft times. It is a 3 piece design, with a hard delrin center (specially designed to articulate like a ball) & has poly side bushings. Again, this is somewhat of a compromise for guys doing limited street use & going FAST & need to stand up to the abuse.


Our NEW "delrin" bushing upgrade (coming out in about 2 weeks) has similar design as above, but has better material than Delrin & better design for middle piece, and sides are custom too that allow even more articulation.

So again, for a general statement of BUSHINGS won't articulate, we have several styles that can easily prove that they can.
===================================

I have never preloaded the suspension myself using the LENGTH of the arms. BUT, it has been done for years & years, and before airbags or modifications to instant centers or anti-roll systems, it was about the ONLY way to do it. Talk to some of the "old-timers" that have been doing it a while, especially on a budget. I could get more info on this, but would rather leave it alone since it is NOT something we recommend or do or need to do.

As it's said in posts above, the lowering brackets on rearend to improve instant center are not the best way to go. Raising the top mounting point on the rearend is a MUCH better way. The "no-hop" bars out there that bolt on the rearend & raise it up actually go too far (like 2-3"), but it still can help, especially on A-body's. The BEST solution is the aftermarket rear housings like 9" or 12 bolts, because most all raise that point something like 1-5/16" where it gives the best instant center. ANY of these can cause bind with some poly bushings if not installed correctly. Adding any brackets & relocating mounting points need to be right on or will cause more problems than they fix.
===================

Basically we have found there is a place & purpose for ALL types of arms & bushings & rod ends, from 13 sec cars to the 7's. We try to offer options to cover a wider range of use & street/strip instead of race-only. But we are making an insane version with rod ends for the super fast guys that are race only, since there is a few needing it out there. Basically we will have several other options later this year to cover the whole spectrum a little better. No single style will be best for a 7 sec daily driver, but our new "delrin" setup will be very close

======================

Our "swaybar" is actually an anti-roll setup somewhat "upside-down" from the weld-in ones that are out there. It is NOT just for 7-8 sec cars!!!!!!! It works awesome on a 12 sec daily driver, and with a slight amount of preload, it works great on a 7 sec racecar. To say that cars don't need them or slower cars don't need them is NOT right. Look at just about ANY new performance car or truck out there, and most cars from '89 & newer (going 15's to 12's), and there is a good chance it has an anti-roll setup on it. They are NOT just for fast race cars.

Even GN/GS cars with new housings & perfect instant center will still benefit from an anti-roll bar setup. Some FAST ones can't launch straight & level without them, regardless of how you adjust the length of the arms. The engine torque (if high enough) will overpower any anti-squat properties the perfect intant center can provide. At 10.80's & not launching on the slicks you probably won't notice. Get slicks & a 1.40 sixty ft time & you will see a very different story.
=================
I'm sure this can be debated forever. One thing is for sure, everyone that uses our swaybar/anti-roll setup LOVES it & would never go back. This is people with raised upper mounting points (no-hops), people with new housings, and ones with totally stock stuff. This is 14 sec cars to the 7's, drivers to all out racecars. I personally have NOT seen an easier way to gain traction, launch straight/level, improve handling, and gain consistency than our setup. I can't say there may be other ways to do it or get it done, but this sure does the trick. Ask ANYONE using it, don't have to take my word for it. Just because "The bar that Dick Miller sells is for 8 second cars", doesn't mean mine is too. They are COMPLETELY different designs & COMPLETELY different performance characteristics.

Anyway, said my peace, not mad, tried to state the facts, just hope someone got their questions answered & some of this figured out. Watch what works & gets into the final rounds at the Nat's

 

[topher455]

Thanks for the reply guys. I had never heard anything about brackets ripping off or bolt holes elongating. That does concern me somewhat since Im running the rod ends. My car should make about 470-500rwhp should I be concerned? I will be running nitto drag radials on the street and at the track. If Im powershifting and leaving hard with it am I gonna rip someting out? I used grade 8 metric bolts when installing the arms since they fit the holes exactly with no movement so there wouldnt be any slop that could cause the holes to wallow out. What do you think?

 

[Jack Armstrong]

I had never heard anything
about brackets ripping off
or bolt holes elongating.

Ninety-nine percent of

those sorts of stories

appear to revolve around

the antique primitive and

crude "SouthSide" arms.


Global West led the way

on Delrin (Del-A-Lum)

bushings & spherical bearings

on lower arms. Edelbrock

uses spherical bearings

(in the front location)

with their upper arms.

Hotchkis also

makes a terrific light &

strong sway bar for G-bods


No concerns like the above

w/anything from those 3.

 

[MSDGN]

The brackets that lower the rear mounting point will change the INSTANT CENTER.

On faster cars, the drop down brackets will "hit" the tires too hard & usually spin them and/or react violently.

This is so true...my car is/was lowered and I thought using the relocation brackets would help...NOT!!...worst mistake I've made with my car...I couldn't launch worth a crap...anything over 10 PSI launch and it would blow the tires away...what a waste of a run...wait an hour to make a run and then that happens...since then I have cut those POS brackets off and also got rid of the drop spindles and lowering springs in the back...car is now back at stock height...haven't been to the track with changes but I'm positive it will launch better now...many...many guys getting great 60 ft times without relocation brackets...IMO...don't use them!!

 

[TurboDave]

a better alternative than the Southside product? LCA relocation bracket?

Is this design any better as a lift bar?

OMG! NOOOOOOOO!!!!
Take my word for it, that second set of bars pictured are an absolute total waste of money on a 4 link suspension like ours.

Those "slapper" bars (as they were/are called) were designed originally for use on leave spring cars. So with a little "red neck" engineering somebody must have thought it would be a good way to separate even more people from their hard earned cash.

I was one of the poor unfortunate fools that tried a set of these about 10 years ago. They are now in the landfill in San Diego.

How stupid was I for thinking slapper bars were going to work on a 4 link suspension.

The ONLY thinks that they managed to do was bind the suspension on street driving, and when they got hit at the track it was one good bounce, and then the suspension unloaded, spun, bounced, unloaded, spun.... well, you get the point.

I'd like to strangle the idiot redneck that designed those bars.

 

[HRpartsNstuff]

Thanks for the reply guys. I had never heard anything about brackets ripping off or bolt holes elongating. That does concern me somewhat since Im running the rod ends. My car should make about 470-500rwhp should I be concerned? I will be running nitto drag radials on the street and at the track. If Im powershifting and leaving hard with it am I gonna rip someting out? I used grade 8 metric bolts when installing the arms since they fit the holes exactly with no movement so there wouldnt be any slop that could cause the holes to wallow out. What do you think?

Basically, the issues like that mostly stem from the old SSM style stuff that was around for years. There is usually some built-in clearance so that you can actually get stuff bolted onto your car without swearing too much . There are clearances between the different material sleeves (bushings) and from the bolt to the inner sleeve dia, and the bolt to the bolt hole.

With the harder nylon or delrin materials with such a thin cross-section (like 3/4 ID & 1" OD), there is NO way it will flex. If the delrin was 3/4 ID & 1-1/2" OD, it would have a chance to dampen the impact a little bit. WIth the lower brackets, the new instant center gets the lowers to push harder & try to lift quicker. That combination of no flex & harder hits is what eventually gets the mounting bolts to loosen just a tiny bit. Then that allows it to shift forward on every launch, and backwards every time you hit the brakes. The longer this is not checked & retightened, the worse it will mess up the brackets.

Even used on the street & never raced will do this. Every chuck hole, every little bump in the road, basically sends a "shock" right thru to the mounting bolts & whatever they connect to. Whatever the weakest link is, that is what will break or oval out or get damaged.

Because of this, ANY rod end, or solid type bushing setup that doesn't flex like rubber or poly will transmit every jarring sensation right thru, whether it's a hard launch or a bump in the road. If you keep the bolts tight, the issue of ovaling out holes is eliminated. I would say a few launches after install to chech them, and maybe every so often after that just to be safe (like every 500 miles or 20 launches or???). It is less likely to come loose with good newer style arms with better designs & better materials, but it can still happen because there is NO flex to take the initial impact & tone it down on the mating parts.

Usually the first thing to see go (if bolts stay tight) will be the forward mounting bracket for the lowers. Once the weld starts cracking, it can rip it right off the frame. When that happens, I hear the lowers go right up into the car & tear out the floor pan & back seat. Not a pretty site. We make braces #0251 to reinfoce this bracket & keep this from happening. Being not a strong weld & getting some years on them & abuse along the way, even cars with std poly can rip them off. It is more related to lower 60 ft times or loose bolts & moving around. It's a fairly easy deal to beef it up BEFORE things come loose. That is also a very good point to connect each side to the other if the car has been frame notched. Keeping the frame rails & this bracket from flexing around will save the rear quarter panels!!!

If running rod end style (which we will have avail soon), we would recommend bracing up EVERY mounting point just to be safe. On older A-body cars, the uppers pull out of the crossmember pretty easily too. Got to be going pretty fast to do it with G-bodies, but it can happen. If on the street and/or racing a lot, it's more important than if you see the track 3 times a year. BUT, one hard launch is all it will take to tear things up! The frame/brackets are only so strong & only attached so good, not desgned for what we do to these cars Red Armstrong once told me EVERY car with poly bushings should brace up that bracket. It is taking the most abuse & stress, and was designed with a rubber bushing to take the shock out of the equation.

Nothing to really stress over, just shouldn't be ignored. Like lug nuts & stuff like that, should be checked every so often if hammering on stuff.

 

[Ttype6]

I had never heard anything about brackets ripping off or bolt holes elongating. That does concern me somewhat since Im running the rod ends. If Im powershifting and leaving hard with it am I gonna rip someting out?

The elongation happens because the bolts become loosend.The thing that loosens the bolts is the stress put on them when the susspension articulates in cars with solid control arm bushings. When the susspention articulates the bars need to twist but can't because the bushings won't allow this to happen. This is what starts the proccess of breaking the mounts loose from the frame,not the forward linear force put on the control arms during accelleration or power shifting. If you have spherical rod ends this is not a concern of yours because they do allow the control arms to twist when the susspention articulates. The lower control arms mounting points at the frame will always benefit from extra bracing.

 

[HRpartsNstuff]

<snip> This is what starts the proccess of breaking the mounts loose from the frame,not the forward linear force put on the control arms during accelleration or power shifting. <snip>

I guess this is where we will have to agree to disagree. I have seen it happen on cars that never had issues of bolts coming loose or binding suspension. The lowers are pushing forward & trying to lift the car, so they do most of the work & take (or transfer) most of the stress. As you "hit" it harder, whether it be off the line or hard shifts or even hard bumps in the road, it WILL be trying to rip the mounting bracket on the forward end of the lower control arm off.

On a 12 sec car it's less of an issue than a 10 sec car. A 10 sec car isn't as bad as an 8 sec car. A transbrake car is worse than a foot brake car. A 1.50 sixty foot time isn't as bad as a 1.35. Poly hits harder than rubber, rod ends hit harder than poly, and loose bolts or too much clearance with nylon/delrin/rodends will hit the hardest. Nitrous V-8 will hit harder than a turbo car. Shift kits hit harder than regular rebuilds. High stall converters will hit with more torque than stock stalls. A 4 speed car is worse than an automatic. GM in the late 60's & early 70's were bracing up these brackets on 4spd cars from the factory with rubber bushings because the brackets were breaking off.

Bottom line, the brackets were only designed to take so much stress & force & impact applied to them. Every car is different too. Seen a low mile car with mild setup have cracked welds. Seen high mile cars with SSM bars for years & no issues (yet). It DOES happen & should NOT be overlooked if upgrading the control arms to any style.

The lower control arms mounting points at the frame will always benefit from extra bracing.

Now we agree again

I guess it's up to what you want to believe & how important it is in YOUR particular situation, and how safe you want to feel. I just go by what I have seen & the 1000's of customers that give us feedback & the "well respected experts" out there that have been doing this for years & years & seen more than me.

To me it's like trailer lug nuts. Some don't check them for years. Some check them twice a trip. But EVERYONE that has a tire come off checks them more often!!! Just trying to get people to be aware BEFORE stuff comes off the car unexpectedly. Hope it helps!

 

[ITSNOTAGN]

I also run the UMI tubular uppers and lowers. Have 30-40k miles on them, and they look like new yet. Also my swaybar has never moved, the backside of the swaybar has knurles on it, and i put it on with a impact gun so it was really tight. The marks it left in the control arm are still sharp, no movement.

Also for a good streetcar, all you really need is good arms, new springs and a good pair of shocks. I dont have problems putting down 600whp with my setup, nothing fancy. You just have to remember, there is only so much hp you can put to the ground in some areas, doesnt matter what suspension you have.
Gary

 

[buttonfly]

Rear Suspension

I'm not going to debate who's the best, who knows the most. I know there is so much that goes into tuning a suspension meaning everything we do is going to have a result. Whether it be POSITIVE OR NEGATIVE. I chose to go with an ATR bar, UMI lower's, and UMI adjustable uppers. I am still learning the car, and trying to figure out how to launch the car. I know it is very simple for some of you. When your getting out of a stroked mustang where all you did was bring the rpms up enough to load the suspension, then hit the bottom amber and the converter did the rest. It was too simple! I am still learning how to launch this car, because I flat out suck at trying to bring up the boost and 60ft the car. I currently have the pinion angle set to 4 degrees, and this winter I am adding a PTC converter. I hope this year I can get a decent 60 ft, but I love the way the car feels and launches now. I can only hope this year I can get that hit out of the hole these cars are known for!!:biggrin: I just wanted to share what has worked for me so far!! J

 

[topher455]

HR parts and Ttype6 thanks for your replies. I was worried about the mounting points when I started building up the rear suspension that is why I installed the hotchkis trailing arm braces and added the crossbar (1" square stock 14ga) that is welded to the gusseted pinion snubber brace and the top edges of the upper arm attaching points and the inner sides of the frame rail (see pic) also my car does not have a notch. I also welded in a similar crossbar to the front and rear frame horns to square up the front and rear frame sections. What do you guys think?

 

[topher455]

Sorry about all the pics I just figured out how to post them without making them tiny.