heel2toe

iTrader: (41)

Well, I always enjoy pressing out the ball joint on those arms; sometimes it's simple and other times the thing wont line up straight which is annoying. I don't know much about machining but figure there must be a way to clamp said piece, but perhaps you'd be forced to make a jog. If thats the case then perhaps there is a simple business in providing this service. it just seems so simple and a silly problem to have.

As far as your 2nd statement about the sleeve getting out of round assuming the sleeve is made out of a stronger material relative to the LCA then why would it distort once pressed inward? It seems pretty simple, make hole round then press in bushing. That's all the PSRS is anyway.

Dallas J

iTrader: (1)

I think this is where I'm settling. I'm going to slightly change directions with a similar architecture but fixed length and 7075 for the main body. I did some quick FEA on my current setup using 2000lbs of braking force and was able to easily pull out a 1lb from the main arm.

So now it'll be about making the best arm for my setup which is pretty aggressive and then maybe looking at longer version for the few people that want it. The most important goals are reaching 8deg of caster and removing stiction on that inner bushing, everything else is gravy

heel2toe

iTrader: (41)

Sounds like a plan but what I don't understand, or should I say one of the many things I don't understand is how can you add caster without changing the position of the wheel?

Dallas J

iTrader: (1)

You absolutely move the wheel, but in my experience theres more room on the front than the backside. I'm going to also be tilting the top back further than I already am to get that full 8deg.

Right now with about 6deg I need the wheel to move forward because of rubbing on back liner. My liners are cut on the front and Ive relocated the bumper bolt to trim that space for clearance as well.

So another 1-1.5deg from the control arm moving wheel forward, and 0.5 deg from top moving back should give me the caster I want and more clearance on the wheel. Getting the full 8deg may require some bumper trimming but when shooting for over 2x the stock setting I figure its going to take a bit of work for anyone trying to fit the most aggressive setups.

That is also why I'm making it adjustable. Everyone is going to want more than stock caster so setting min to 1deg would be great. Then adjust forward as far as you can tolerate.

LetsGetThisDone

iTrader: (1)

PSRS has a boat load of material around the bearing bore, not the case in the front location. Cusco makes a spherical bearing kit for it, but it's about $300...

Dallas J

iTrader: (1)

And that's what I think is stupid. $300 + install and it only fixes one of the joints and leaves everything else unadjustable. I figure for under a grand we can have lighter and more useful arms for racing.

LetsGetThisDone

iTrader: (1)

Exactly. That $300 + $250 for the whiteline KCA400 you're at $550 already. A shop will charge you $100 to install those parts in arms that you took off the car yourself. So you're well over halfway to a legit set of arms like what you're currently designing.

Dallas J

iTrader: (1)

Add in the WL RCK (which is honestly a waste of money IMO, only corrects like 5mm) and it gets worse. I'm obviously biased and most wouldn't ever be worried about a perfect solution.

heel2toe

iTrader: (41)

Ahh gotcha I was sitting here scratching my head pondering how that would be possible. I saw pictures of the pates you made and Im wondering if you can actually squeak out any more caster out of them. Im sitting at around 6.1 degrees myself with the PSRS and CDR plates and my wheels are just about perfectly centered and have minimal rubbing of what left of the liner with a 285/30 on my 18x10.5 +30 wheels and 17mm spacer.

Id imagine your plates probably give just about the same amount of caster and to that end I dont see how you could possibly move it inward anymore. With my setup I'm out of space where the allen bolts that adjust for camber are hitting the top of the strut tower. Myself probably like many others compensated by installed 3 allen bolts on 1 side and 1 on the other to make some space. But the thing is maxxed out now. You're a creative guy so perhaps you have something up your sleeve but I cant fathom how you get over that hurdle without notching into the tower.

I do agree however that mowing the wheel forward is the better route vs backwards as trimming the bumper and lip is simple relative to trimming that steel by the pinch weld. But once again it can only go so far forward and ideally with movement forward you compensate at the top to dring it back again but youre limited there.

Yes, totally agree but was just making an analogy in that it shouldnt be that hard to design.

So what is it about the Cusco piece that allows it to work then? I get that the holes are out of round but theres gotta be a point where close enough is just right. This shouldnt be rocket science. Make sleeve press spherical into sleeve press bushing into LCA make spacers for inner race profit.

I have the WL horizontal bushing and its always bothered me in that position. $300 for the spherical is sily for what it is but I've got everything else so it's an easier pill to swallow relative to new arms. But hey if you can come up with something for <$1000 I could always sell my arms to offset the cost. A set of arms stock arms with all the fixin's should yield at least $500 I'd imagine.

What is your plan for the ball joint and fixing the roll centers? Or is that all taken care of already with your uprights?

Im all about bang for the buck. Unfortunately, my car is at the point where everything easy is done and now its gets expensive really quickly and much more creativity is needed. If you keep coming up with these sweet parts Im going to have a tough time deciding what will be the best bang for the buck. Ill have to come up with a time saved on 60 second run vs dollar spent ratio

LetsGetThisDone

iTrader: (1)

Will this arm not need to use the RCK?

heel2toe

iTrader: (41)

I've seen you say that before but what's the alternatives? I've yet to find a kit that offers more correction and is readily available. I have nothing against WL as a company and have pretty much every bushing they make for our cars but for some reason the RCCK doesnt seem to hold up too well. Mine failed after 2 seasons however I will say that they send a a new kit so at least its a company that stands behind their products.

Dallas J

iTrader: (1)

Don't get me wrong, I think the WL RCK is a great solution for replacing the stock ball joint if it goes back since I don't think there are any other options. I just think the actually correction amount is so minimal that doing it by itself will yield far to minimal of a gain. Getting back to that $/time gain, I would say its pretty low if you have to pay for it to get pressed in and alignment.

I originally wanted to use the WL ball joint but I cant find a source for it by itself so I'm just planning on having my own stud made. that will fit on a 19mm spherical with a threaded hole in the end for a bolt to capture it all.

I think making that part adjustable is the wrong move though. At around 2000lbs braking force, the stock part is right at the yield strength of steel and going longer is just too risky IMO. That 2000lbs braking force limit of the stock part is also why I'm designing mine around a 2000lb load limit along with looking at deflection <1mm.

If you search for the moonface ball joint, its actually longer then the WL but people have been bending them on track. I think we're really close to the functional limit of length without risk which I'm guessing most people would like to know and stay within the safe range.

alpinaturbo

iTrader: (5)

Robi charges modest amount for front spherical, perhaps little more than $100.
Indeed there has been fit issue:

The spherical bearing "insert" sleeve that sizes spherical bearing bore to bolt OD was undersized.
But that easily sorted by measuring before installation and honing as required.

With GC Top Mounts, Evo X arms, WL RCK, PSRS & Robi front spherical, I am at 5 degrees or little more caster.
Can gain maybe 0.5 more for when 6..6.5 max.

My wheels are as close to front bumper as possible without major surgery - I would not want to do to a nice car.

I run good amount of rake, but even with flatter ride and pushing tops full back with little customization, I'd say 6.5 max caster while still respecting bodywork.

Dallas J

iTrader: (1)

Moving the top back more is definitely going to be the trick I think. So my personal plan is this, since I am shooting for less camber due to max caster I'll max out camber at the strut and remove it at the top hat. This will do two thing, one good one not great. The good is decreased SAI, the not great is decreased slider axis. But moving the strut top back means I can tilt it over much further back.

Pictures I have of my offset plates are 15mm offset. I can get another 5mm there using the single rear (relative to the car) bolt, or if I do some tricky stuff I can move it another 10+. I'm thinking I may just make a non-adjustable plate to really max out the angles up top.

There are clearance issues on the bolts that hold the camber plates in place (the ones coming thru the car to the top) but that will be fixed by moving to a 3/8" plate and Flat head socket screws so its just flush on the bottom side. Ill core out the plate in low stress areas to decrease the weight of course

I also think I might already be a little further back than others (my plates being 15mm where others are using 10mm offsets like Vorshlag) and I'm rubbing a lot on the rear fenders well with my 295s. So I feel I have lots of room in front of the tire.

So moving the bottom forward about 20mm will give 2deg and top back another 10mm will give another 1 deg. That's how I go from 5-6deg to 8+. Ill be at around 3deg of camber static and adjust it probably from the strut bolts and not strut top (which is how I do it anyways).

Make sense? It may be a pipe dream but I know in the end I will find the caster that caster limit.

heel2toe

iTrader: (41)

This is exactly what Im talking about in regards to those allen bolts hitting the strut tower. So I think I get what you're saying here about countersinking the bolts however that leads me with one more question for you sir. If the heads are countersunk that eliminated the issue of the bolt heads hitting. However how do you then adjust for camber at the top assuming the bolts that would be hitting are now under the strut tower?