LCA caster mod question

[Hindsight]

I did what several others did for the caster mod: Sandwich a piece of 3/8" thick aluminum between the LCA and the rear LCA bushing. However, now that I have done that, the rear bushing won't fit onto the mount. I had a "duh, what did you think would happen?" moment when I realized this, but what I can't figure out is: What are people doing about this? I don't recall reading anything where someone mentioned how they got everything to fit right after doing this. There really isn't enough metal on the frame bracket to drill another hole, especially not where it needs to be. I could make everything bolt up by just forcing the control arm over, but doing that would be a ton of stress on the front bushing which can't be good.

http://i.imgur.com/9yvJm4o.jpg

[Jaime]

If you move the mount in 3/8 of an inch, it defeats the point of the mod. You have to push the rear tip of the LCA outboard so that it pushes the outboard tip forward.

[Samiam1017]

mine fell right into place no problems????

[Hindsight]

If you move the mount in 3/8 of an inch, it defeats the point of the mod.

lol, yeah, duh, that makes sense. But what I'm still confused about is if doing that is ok for the front bushing. That bushing gets really twisted when you push the rear LCA outward. I imagine it's very hard on the bushing and could cause premature failure or some other possible issues. Any idea?

[Ironhydroxide]

if you're worried about bushing life, buy a stock car.

my solution to this would be to find a Heim style bearing and replace the bushing with said bearing and spacers to make it work.

Something like page #32 in this brocure http://www.rbcbearings.com/literature/pdfs/Heim.pdf

Looks like with the right spacers you could have anywhere from 7 to 34 degrees of misalignment depending on the bearing you choose. Sounds perfect to me, as we're dealing in single digit degrees here.

you're welcome.

[Hindsight]

Thanks for the reply. Regarding bushing life, I don't care if it only lasts like 10k miles on a car like this. I just worry about it failing much sooner than that and being all mushy. If someone who's done this before on a WRX or 818 says it's nothing to be concerned with, then that would be good enough for me.

Cool idea about the heim bearing though!

One other thing: In google searching for this issue, I found posts on various subaru forums where people are rotating the rear bushing 180 degrees (effectively moving it upside down) to get half a degree more caster. If you look at the pic above, you can see how the black portion of bushing bracket is offset, and flipping it 180 would push the rear of the control arm out a bit in the proper direction. I may just do this instead of running the spacer....I guess. It won't give as much caster but maybe it would be enough.....

[Ironhydroxide]

for a car like this, for me, I'd do the bearing.

on my daily I have the Whiteline RCA kit and have done the "free caster mod" on stock bushings for 15K when I pulled them and went to Poly front bushings.

[C.Plavan]

You dont need the 3/8" aluminum. Just flip the black stem mount 180 degrees so the "rounded edge" is towards the control arm. its offset. Then just make it fit. :)

See your picture: Ditch the aluminum and just flip the stem.
http://i.imgur.com/9yvJm4o.jpg

[Hindsight]

Thanks Chad, will do.

[JeromeS13]

Yeah, I didn't worry about the front bushing either. No ill effects so far.

Also, I rotated my mount AND put a small block in there.

[tmoretta]

My entire suspension is assembled. What has to be removed to accomplish this mod? Is it worth it? Would bolting the stem mount to the outer holes instead of the 818S prescribed inner holes accomplish the same caster improvement?

[Goldwing]

I added my spacer after the LCA was installed while fussing with my tire rubbing issue. I never loosened the rear wing mount. The bushings are compressed, and is a valid concern. With wrx guys doing it, I was figuring no reports of problems on daily driven cars, with far more weight being supported, I should be alright, but figured I'd keep an eye on it to be sure. If I didn't need it for tire fitment...

[metros]

I was looking at the same thing the other day. Any reason for the s builders not to use the r mounting holes in the above pictures? That would essentially add the castor without flipping the bushing or adding a spacer.

[Bob_n_Cincy]

I was looking at the same thing the other day. Any reason for the s builders not to use the r mounting holes in the above pictures? That would essentially add the castor without flipping the bushing or adding a spacer.
Hi Metros'
good observation, but the outer holes on the LCA rear bushing mount are the for wagon donors that have shorter LCAs.
Three methods;
1. flipping rear bushing pin on the alum. (free caster) LCAs.
2. Adding spacer block to alum LCAs.
3. Using outer mounting hole in bushing mount.

All three put stress on the front bushing. Bad or not, I don't know.
All three change the change the intended arc of the lower ball joint, so this might cause some bump steer.

Has anyone at ffr made any of these recommendations?

Bob

[Jaime]

It should be fairly easy to relieve the stress on the front bushing. Just open up the front hole a bit - it shouldn't take more than 1/32nd or 1/16th.

[Ironhydroxide]

It should be fairly easy to relieve the stress on the front bushing. Just open up the front hole a bit - it shouldn't take more than 1/32nd or 1/16th.

The problem with that is the flanges are still in a perpendicular line with where the rear pivot normally goes. When you tighten the bolt down the center of the bushing moves back to parallel with where the rear pivot should go. Therefore, Widening the holes just gives you variance in the mounting which is never a good thing.

[tmoretta]

I am also thinking that using the outer (wagon) mounting holes for the rear bushing mount will move the front hubs/wheels forward a bit. Will the wheels then sit awkwardly in the front fenders?