Tubular Front control arms - Discussion

[CSI_MuNkY]

Yeah, its that topic again, and yes, I feel this deserves a new thread.

 

I found a company locally that does all the framework for Legendary Motorcar (don't know them? look them up!) as well as the powder coater that LMC uses.

 

I have contacted them about the possibility of making front tubular control arms for our cars, and maybe even rears

 

My reason for starting this thread is to determine a general consensus on what everyone here would like to see in a tubular control arm and what you think it would be worth. Or better yet, what you don't want to see.

 

 

My usual supplier of formed materials put me on to this company when I asked to get some material formed that was outside their capabilities. After checking out their website I thought they would be a great source for this sort of thing.

Right now I have asked him for a price for a one off set, I figure that will be a worst case scenario. I sent him a picture of our stock arms, and told him that I have a spare set I could send them.

 

Some things to consider;

What would you want them made of?

What kind of joints would you want to see?

How much would you want to pay, max?

Edited April 16, 2012 by CSI_MuNkY

[White93z34]

What I want to see is simple:

 

 

• stock balljoint location
  
• poly bushings that fit into stock location on the subframe
  
• good swaybar mounting point
  
• can take or leave adjustable turnbuckles, not a big deal to me either way
  

 

don't want:

 

 

• helm joints that require spacers to properly fit subframe
  
• helm joints period.
  

 

as for what its worth... not really up to me to decide. Not like I'd have much input anyhow as I'd prefer to pay as little as possible but with a 100% custom item that probably not even a dozen people will buy in the end its going to be pricy, not any real way to get around that. All said I am interested.

Edited April 16, 2012 by White93z34

[xtremerevolution]

Made of something that doesn't rust quite that easily. Something that you can bolt up to stock balljoints, stock everything.

 

It might be nice to have the option for a balljoint spacer built into the design for obvious reasons.

 

Poly control arm bushings would be preferable. Solid is nice, but you'd increase the number of people who would want a set if you made them just a bit more comfortable.

[CSI_MuNkY]

I would get everything powder coated by the same guy that LMC uses. I had him do my batch of engine bay parts and they turned out fantastic.

Crappy Cell phone pic is all I have with me right now

[RobertISaar]

man, this is like the 60V6 aftermarket roller rocker thread, just keeps coming back from the dead.

 

for those of us that are less suspension tech inclined(myself being one), what kind of benefits are we talking about? the 90GP had both control arms rust through and break at roughly the same time.

 

i get the feeling that these are only going to be REALLY helpful for the track friendly cars?

[CSI_MuNkY]

Depends on what you do, would I recommend them for someone that DD's there car and nothing more? no. They are definitely more gear towards the people that race their cars, or push their cars hard in corners just for shits and giggles.

 

They are more rigid that OEM arms. Just like doing the Poly bushing swap in your OEM arms, you will notice handling gains because of the stiffness. But there is no way of knowing how much, without actually doing it.

Depending on how they are made, you also gain adjustability for bringing the suspension into more ideal angles. This would benefit us when lowering our cars by giving us a means to correct ball joint angles as Andrei mentioned.

Alternatively, these would most definitely be heavier than stock.

 

I'm not going to turn this into a sales thread. I understand that the people interested in these are few and far between, and advantages are limited. I am definitely not trying to make money on this idea, I want them for myself, and if a few other people can benefit from that, great.

[skitchin]

Need new control arms here, tentative based on price. Wants: Direct bolt in replacement

[rich17]

I'm sorry but if we were to go this far why wouldnt we make them fit 2nd gen knuckles and struts? The benifits of it would be amazing. AGX's. Fbody or even GXP brakes. No alxe issues on HD trannies. It'll be harder to get the geometry right would be better IMO

[AWeb80]

I'm with Chris. If they have a stock BJ location and come with poly bushings and a good sway bar mount. I'm interested. If they are lighter than the stock ones, I'm even more interested. That's the biggest plus right there. It would lead to better response over bumps (less weight being thrown around leads to being easier for the spring/strut to control it). I'm no engineer, but I think our stock ones are plenty strong for even the little some of us track our cars. The biggest gain I'd look for is lighter weight. So that right there, determines the material and I'll leave that up to you.

 

If you start to get too fancy with them ex: helm joints, different BJ angles and such - the more, I think, people will turn away from this. Plug and play would be your best option. Poly across the board is the way to go, no solid mounts. Sure poly is a bit more stiff, but I'd DD a 'stiffer' suspension like mine any day.

 

Now for the kicker, my interest in my car has slowed a bit (not going to sell it) so spending lots on certain things doesn't appeal as much....but if these were $400 or under and I can plug-and-play them, I'm pretty sure I'd be in.

Edited April 17, 2012 by AWeb80

[jman093]

We'll I unfortunately sold my old autox GTP, so I don't really have a vote here, but I can't help give my $.02 as this interests me immensely. I bet most members are going to want basically the stock lower control arms in a tubular form w/ the poly bushings. This makes no sense at the price point these are going to run. You can just put poly bushings on the stock arms and it would be just as well. The small weight savings of the tubular pieces will provide next to nothing performance wise. If you're going to spend the money get something that's going to increase performance. That leaves 2 options as I see it.

 

1. Going with a stock style arm, but moving the ball joint (outward and forward) to get more caster and more negative camber. It doesn't have to be a lot, or provide crazy autoX alignment angles, but just something better than stock. These cars need all the help they can get here. Stock alignment is horrible from the factory. Camber is positive and there's very little caster. On my GTP, I was grinding on the subframe and strut towers to move stuff around to get better specs, but you can only get so much without really going bonkers with the grinder. Even with that, I was still running way too much on the outside of the tires at AutoX. Also, a tall ball joint option would help the camber curve some and/or undo the damage lowering the car does to the curve. I would have loved to have seen this, but I'm guessing most members would probably want factory ball joints, but I could be wrong. At the very least do something about the alignment specs. Something street friendly, but more performance oriented. It's a waste of money if left stock other than to just say, "OMG I HAVE TUBULAR CONTROL ARMS!"

 

2. The other way to better handling is go 2nd gen compatible as Rich pointed out. I would have loved this as well, but again, I bet it only interests a few of us racing-minded members. AGX struts and other performance parts, more easily adjustable camber, C5 Z06 brakes. and it's probably lighter as well with the aluminum knuckle. I'm guessing ABS would have to be ditched if going this route though, and I'm not sure what the compatibility with gen 1 CV shafts or hub & bearings is.

Edited April 17, 2012 by jman093

[Mach 5]

I would be down for a set of heim joint front arms and a set of poly bushing arms as well. one for my daily tgp and one from my drag tgp. What we looking at as far as pricing is concerned?? I remember DOHC V6 had these up a while back but I guess that ddint really work out. I also like having the option of possibly integrating a ball joinjt spacer maybe around 1inch thick to get the arm back at proper height. I have a set on my ae86 and is totally needed when you lower you car. Im sure the problem with that is going to be that you need larger than 16inch wheels..

[CSI_MuNkY]

I think the way I am looking at doing this is with options. If the arms have threaded bungs in them then you could select heim joints or poly bushings.

 

Could someone show me a pic of a ball joint spacer installed? I'm intrigued... I'm guessing this would keep all the drive line components in place along with the strut knuckle, but would effectively lower the end of the control arm, therefor correcting the angle? How thick would such a spacer have to be?

 

I will not be going 2nd gen. If someone else wants to, all the power to you. In my case, I have no interest in the biggest thing people seem to go gen 2 for, bigger brakes. I'm running cross laces and its staying that way, I can't fit much more brake in there.

[CSI_MuNkY]

Ok so his budgetary number is in the range of $390 per set if we sell 10 sets. $500 a pair for a one off set. That would be with Poly bushings. I am going to e-mail him back and bounce some ideas off him, see what his thoughts are.

[Mach 5]

I think the way I am looking at doing this is with options. If the arms have threaded bungs in them then you could select heim joints or poly bushings.

 

Could someone show me a pic of a ball joint spacer installed? I'm intrigued... I'm guessing this would keep all the drive line components in place along with the strut knuckle, but would effectively lower the end of the control arm, therefor correcting the angle? How thick would such a spacer have to be?

 

I will not be going 2nd gen. If someone else wants to, all the power to you. In my case, I have no interest in the biggest thing people seem to go gen 2 for, bigger brakes. I'm running cross laces and its staying that way, I can't fit much more brake in there.

 

 

An inch should be fine. basically just need to make sure the arms arent level or below level. also since the tie rods mount of them strut that would have to be lowered as well to keep the angles the same.

[White93z34]

that price point is not unreasonable, I'd pay that for something that just works how its supposed to. I do not think you'll find 10 people total to go in, that said, I'm in.

[Schurkey]

I bet most members are going to want basically the stock lower control arms in a tubular form w/ the poly bushings. This makes no sense at the price point these are going to run. You can just put poly bushings on the stock arms and it would be just as well. The small weight savings of the tubular pieces will provide next to nothing performance wise. If you're going to spend the money get something that's going to increase performance.

 

<SNIP>

VERY, VERY smart post.

 

It will be pointless to go through that much work--for a part selling for big bucks--and not see a performance difference that can't be matched by a simple bushing swap into non-rusted stock arms.

[gtp237]

No offense but there's no point in tubular control arms when you can just put urethane bushings in the stockers.

 

And for the record f-body brakes fit under crosslaces, weigh half as much and stop you like 3 times quicker than stock brakes ever could with any pad/rotor configuration.

[jman093]

Could someone show me a pic of a ball joint spacer installed? I'm intrigued... I'm guessing this would k

 

An inch should be fine. basically just need to make sure the arms arent level or below level. also since the tie rods mount of them strut that would have to be lowered as well to keep the angles the same.

 

No, no, no, no guys. Do not "space" the control arms. That will not change a single thing. The change in control arm angle and the subsequent loss of negative camber gain is due to the shorter length between the lower ball joint and the center of the upper strut mount point. The control arm is following the arc it makes between its subframe mounting point and the lower ball joint. The ball joint mounts onto the knuckle pointing downards so spacing the control arms will not change the pivot point (which is the center of the ball joint). Hypothetically you could make the arms zig-zag, loop around, space them 10 inches, whatever; it actually would change absolutely nothing since the mounting points on the subframe and the ball joint attached to the knuckle are in the exact same spot. The only way to correct the angle would be to put a spacer between the knuckle and the lower ball joint. If you lowered the car three inches, a 3 inch spacer would restore proper angle. Obviously a 3 inch spacer isn't feasible, so we just have to live with the limitations of a MacPherson strut suspesion.

 

I'm not really sure how of much a loss in the camber curve there is from stock on a car lowered a couple inches. It could be completely negligible, it could make somewhat of a difference. I don't know. It would take some measuring and geometrical calculations to know for sure. Either way, the way to better handling is to design the arm to provide more caster and more negative camber.

Edited April 18, 2012 by jman093

[BXX]

Its not so much as correcting camber curves, as much as it is correcting roll centers.

 

 

And tubular arm's are feasible based on the packaging constaints of the arm design. I went over it with my welder.

 

Hence I started working on modding the cradle for use with Gen 2 control arms.

[Schurkey]

f-body brakes fit under crosslaces, weigh half as much and stop you like 3 times quicker than stock brakes ever could with any pad/rotor configuration.

Photos and a parts list???

[jman093]

Its not so much as correcting camber curves, as much as it is correcting roll centers.

 

Well maybe, but even that is still going to be determined by the suspension's pick-up points. Roll center, instant center, and camber curve will all be unaffected by "spacers" on the control arm. That was the point I was trying to make.

[gtp237]

You guys shouldn't worry about the balljoint issue so much. Yes when you lower 3-4" the control arm points upward but it does not affect camber the way you guys are thinking. I've had my car as low as you can possibly go on a w-body and my tires wear perfectly even. In fact before I lowered and installed urethane control arm bushings my car would slide forward in a straight line around hard turns.

[gtp237]

Photos and a parts list???

You need second gen knuckles which require custom made control arms.

[Mach 5]

what happens when car is lowered is that it creates bump steer. It may be more noticeable on lighter cars I know my ae86 felt like it was tracking all over the place and felt like it was going to spin till I installed the rca's as long as the arms arfent level it will keep the car from being at the center of the arc which allows the toe to become screwy constantly changing with travel. problem is with rca's it doesnt also correct the steering arm angle so a spacer of the same size would have to be made for that as well. I would be down for just a set of heim joint arms, tubular or not just so when I ppump all the power I plan to put down I wont really have wheel hop and it should hook better overall. but even for my daily a stock set that doesnt flex will def help a ton I know the poly inserts did a number.. much tighter and less understeer on the stock supsension

[gtp237]

Mach 5, I don't have bump steer issues. W-body's seem to have very forgiving suspension. Do you have stock control arm bushings and strut mounts? That may contribute to your bump steer. There's also a ton of heim joint bump steer "fix" kits out there to solve this problem.