• Welcome to the Contour Enthusiasts Group, the best resource for the Ford Contour and Mercury Mystique.

    You can register to join the community.

Daily driveable/track ready front arm concept developement

K

KAOS_3.0

Hard-core CEG'er
Joined
May 16, 2008
Messages
2,997
Location
SE / CLT,NC / ATL,GA
just starting off the thread. so far from what I can gather the most applicable options would be:

A) a 4 bolt swap with the LCA's boxed in and delrin bushings pressed in.

B) press out the oem bushings in two bolt LCA's and the reinforce them somehow, either by boxing with a plate welded on the bottom, or with small dom tubing welded against the outer rolled edge of the triangle as bracing, and then welding or pressing in steel adapters for spherical joints.

option B would be more widely applicable and would probably be the best solution for most cars since 4 bolt subframes aren't widely available and would be more labor intensive for anyone attempting to install the new arms...

on the other hand, option b would clearly be the easiest to produce and would require the least custom work in the development of the arms...

I'll just leave it here for discussion, maybe some experts will join in...
 
I dunno man. Seems kind of a waste.

I autocross REGULARLY on OEM 2-bolt control arms, and I have no complaints. There are plenty more weak links in the system before the A-arms become an issue.
 
well if we build strong enough arms then the only wear part would be the ball joints and possibly the delrin bushings if we went that way. hard to know what your missing if you havent driven a car with track control arms. I thought the contour handled nice untill I drove a prelude with double wishbone up front... slow as hell, but it turnes in like a slot car....

also, for autoX everybody runs enormous swaybars, which take a fair bit of the load off of the flimsy stamped control arms. I'm going to be running the smallest possible sway bars because I like to go fast on actual road surfaces...

this is all of course subjective and off topic. the point of the thread is to discuss improving upon what was available stock...
 
Reason 1 why solution A is more involved than you think:




Because of their shape, both shafts on both arms would have to be re-made from scratch without the dip and bulge to be able to make a urethane/delrin bushing solution.
 
Pole120 said:
Because of their shape, both shafts on both arms would have to be re-made from scratch without the dip and bulge to be able to make a urethane/delrin bushing solution.
Click to expand...
What is the Shore hardness equivalent of delrin ? too hard to compress ?

KAOS_3.0 said:
just starting off the thread. so far from what I can gather the most applicable options would be:

A) a 4 bolt swap with the LCA's boxed in and delrin bushings pressed in. ...
Click to expand...


do you think for road/track use in a group buy;

make a urethane bush 1 or 2mm oversize, by pouring in to an oversized mould with the OEM shaft running thru it. Remove mould, press in to the OEM collar. These could be returned to guys to press in to their arms.

I'm thinking, if it were made with the urethane compressed inside the collar, it would perform better than just pouring it in to the arm. I'm also thinking it would resist walking better.

Being harder than urethane, would delrin rattle once it began to wear ? ...G.
 
delrin wears a bit fast, but it's about the hardness of a golf ball. I'm going to have delrin subframe bushings made. it they make me happy, I can get a group buy together... the stuff is mainly for track use, but it's also wicked cheap to have machined. in the subframe bushing location they wont see much motion, so they should be ok for daily use. in a control arm, you might have to replace them every year or two depending on what you do with the car...
 
KAOS_3.0 said:
I'm going to have delrin subframe bushings made. it they make me happy, I can get a group buy together...
Click to expand...
One thing to keep in mind with Delrin, it will cold flow (creep) under compression. Long ago and far away, someone made some Taurus SHO front subframe bushings from Delrin, and they were forever loosening up due to compression creep. You'd set the torque, and a month later, they'd need re-torqued. The only way to do this right is to make the bushings with an internal steel or Aluminum crush sleeve that allows the thru bolt to keep itself in tension and not go loose.

If the full Aluminum subframe bushing are too immediate, perhaps machining Ultra-high-molecular-weight polyethylene (UHMW) washers to capture the subframe between the Aluminum bushing surfaces would soften up the interface. I use UHMW washers between the spring ends and spring preches of race spring coilovers, it makes them a bit more tolerable on the street.

I've wanted to build some press-in spherical bearing carriers for the 2-bolt A-arms for some time, but the low cost of new LCA's and the fact that I neither track nor autocross the car makes it a non-starter for me. One could design a steel carrier that pressed in and would be secured by a few tack welds, then retain a good 12mm bore spherical bearing with a shoulder and internal snap ring, but at four per car, this isn't going to happen under your $300 target unless we can make 20 or more sets (80 pieces), I'd wager.
 
gmorrell said:
One thing to keep in mind with Delrin, it will cold flow (creep) under compression. Long ago and far away, someone made some Taurus SHO front subframe bushings from Delrin, and they were forever loosening up due to compression creep. You'd set the torque, and a month later, they'd need re-torqued. The only way to do this right is to make the bushings with an internal steel or Aluminum crush sleeve that allows the thru bolt to keep itself in tension and not go loose.

If the full Aluminum subframe bushing are too immediate, perhaps machining Ultra-high-molecular-weight polyethylene (UHMW) washers to capture the subframe between the Aluminum bushing surfaces would soften up the interface. I use UHMW washers between the spring ends and spring preches of race spring coilovers, it makes them a bit more tolerable on the street.

I've wanted to build some press-in spherical bearing carriers for the 2-bolt A-arms for some time, but the low cost of new LCA's and the fact that I neither track nor autocross the car makes it a non-starter for me. One could design a steel carrier that pressed in and would be secured by a few tack welds, then retain a good 12mm bore spherical bearing with a shoulder and internal snap ring, but at four per car, this isn't going to happen under your $300 target unless we can make 20 or more sets (80 pieces), I'd wager.
Click to expand...

good info here, didn't realize delrin crushed down so fast. how long was it in between retorques? I'll also have to take a look at the cost of some spherical joints to get a good idea on pricing...
 
KAOS_3.0 said:
could something like this simply be welded onto the end of the control arm with the lip where the rubber bearing is ground down?


http://int.rsdelivers.com/product/igus/efsm-12/4bolt-flange-spherical-bearing-12mm-bore/4779384.aspx

seems like It would reduce some of the cost in machine work...
Click to expand...

The maximum static radial load of the 12mm bore part (EFSM-12) is barely 600 pounds, wouldn't want that locating control arms in a 3,000 pound car. 1G of lateral loading from a sticky tire would finish it.

To give you a comparison, an Aurora COM-M12T, a 12mm bore, Teflon lined spherical has a max static radial load of 25,360 pounds, this is a part that is easily up to loads seen in vehicle suspensions.

I need to make some measurements to see if a normal 13º bearing can be used, or if a high mis-alignment bearing is needed, I don't know offhand what the movement freedom of the Contour LCA is.
 
Pole120 said:
I already make them out of AL. Not sure why you'd bother with delrin.
Click to expand...

at least a small amount of vibration dampening was the idea...

gmorrell said:
The maximum static radial load of the 12mm bore part (EFSM-12) is barely 600 pounds, wouldn't want that locating control arms in a 3,000 pound car. 1G of lateral loading from a sticky tire would finish it.

To give you a comparison, an Aurora COM-M12T, a 12mm bore, Teflon lined spherical has a max static radial load of 25,360 pounds, this is a part that is easily up to loads seen in vehicle suspensions.

I need to make some measurements to see if a normal 13º bearing can be used, or if a high mis-alignment bearing is needed, I don't know offhand what the movement freedom of the Contour LCA is.
Click to expand...

I didnt mean those exact bushings, just that something already set up in a plate might make them easier to implement. posted those from work in a hurry, obviously those wouldnt work, they are dry self lubricating plastic parts. at this point my mind is wondering about drilling out factory lower ball joints and bolting them into all three laces on a reinforced arm... can't remember off hand what the bottom side of a factory ball joint looks like on these... isnt it just a plastic cup covering the other side?
 
Pole120 said:
You won't notice the difference...
Click to expand...

I'll have to get a set of those then. right now I'm trying to imrove turn in on what's effectively a daily driver and I dont want flakey stamped rubber bushing arms in the front. I haven't been out under the cougar in a few days, but I'm liking the idea of basically a boxed in oem two bolt arm with ball joints at all three corners...

how much do you think something like this would cost from PRT?

from what I can tell a good solid LCA with solid mechanical joints and poly filled roll resistors should have only the wheel hop allowed by the tire's side walls...
 
KAOS_3.0 said:
I'll have to get a set of those then. right now I'm trying to imrove turn in on what's effectively a daily driver and I dont want flakey stamped rubber bushing arms in the front. I haven't been out under the cougar in a few days, but I'm liking the idea of basically a boxed in oem two bolt arm with ball joints at all three corners...

how much do you think something like this would cost from PRT?



from what I can tell a good solid LCA with solid mechanical joints and poly filled roll resistors should have only the wheel hop allowed by the tire's side walls...
Click to expand...

Would have to price parts. Ball joints at all three corners? Stock LBJ and (2) spherical bearings.
 
any developments on sourcing the spherical joints?

I think I may have come up with a novel way to box/reinforce the oem arms...

also, is there any reason the spherical joints couldn't be located in the arms with 94a poly poured into the space between the joint outer collar and the inner opening in the arm? would be much simpler than machining steel adapters and welding them in...
 
KAOS_3.0 said:
any developments on sourcing the spherical joints?

I think I may have come up with a novel way to box/reinforce the oem arms...

also, is there any reason the spherical joints couldn't be located in the arms with 94a poly poured into the space between the joint outer collar and the inner opening in the arm? would be much simpler than machining steel adapters and welding them in...
Click to expand...

They'll pop right out of the urethane. Sourcing the joints was never an issue, I can get them at any time.

You're talking about boxing the arms and installing the spherical bearings to tighten things up, then you want to encase them in urethane to soften them up again. Just install a pair of brand new arms and be done with it then. I hate that I always come off rude when addressing your questions, but rarely do any of the extra steps offer any real benefit over a simple, tried an true, solution. I daily drove the track car more than a few times with solid everything. My tooth fillings are all still in place and anyone who drove it can tell you that it's entirely street-able. My Cougar had solid tubular Stangkiller front LCAs. You got better road feel, and that's it. There was nothing annoying about any of it. Go all the way or don't bother in this instance is what I'm saying.
 
You must log in or register to reply here.
Back
Top