Cast Arms w/Stamped Double Pivot K-Member?...

[zin]

Just wondering if anyone knows if the stamped-arm double pivot K-member will allow one to bolt-in the cast arms from the newer cars?

I seem to recall them not being compatible, but didn't find the thread to verify it, and my K-member has the 1 1/8" bar in it, so I'd like to keep it if I can just swap out the arms...

I imagine I could modify the bar to work with the cast arm K-member if I had to, but I'm trying to do this as easy/cheap as possible, you know, the T-M way!

Thanks for any help!

Mike

[Reaper1]

They are interchangeable. The problem lies with the balljoint position, which is determined by where the hole is bored in the cast control arms. It's been found that the position of the balljoint hole in the cast arms can vary and that is most probably where some of us have run into an interface issue with the front of the wheel well.

[Force Fed Mopar]

I've swapped between stamped Lebaron arms and cast 93 Shadow arms w/ no problems.

[zin]

That's what I was wanting to hear!

I want the cast arms for the added caster, but wasn't enthused about dropping the K-member.

When using the cast arms, did the stamped anti-roll bar still work, or?

Mike

[cordes]

That's what I was wanting to hear!

I want the cast arms for the added caster, but wasn't enthused about dropping the K-member.

When using the cast arms, did the stamped anti-roll bar still work, or?

Mike

I believe the bars are different, but I'm not sure if one could be used with the other. I'm sure if you did the end link mod it wouldn't matter at all which you used. Why not add some caster with Rich's plates?

IMO the advantage of having the lower ball joint in relation to the axle with the cast arm knuckle/stamped arm combination is worth any of the potential down sides.

[Force Fed Mopar]

That's what I was wanting to hear!

I want the cast arms for the added caster, but wasn't enthused about dropping the K-member.

When using the cast arms, did the stamped anti-roll bar still work, or?

Mike

Have to use the cast swaybar.

I believe the bars are different, but I'm not sure if one could be used with the other. I'm sure if you did the end link mod it wouldn't matter at all which you used. Why not add some caster with Rich's plates?

IMO the advantage of having the lower ball joint in relation to the axle with the cast arm knuckle/stamped arm combination is worth any of the potential down sides.

Balljoint is in the same place regardless of whether you use stamped or cast arms. Maybe vans have it located further forward in the arm, but the vertical position is determined by the knuckle.

[Reaper1]

Balljoint is in the same place regardless of whether you use stamped or cast arms. Maybe vans have it located further forward in the arm, but the vertical position is determined by the knuckle.

You mean vertically, correct? The fore/aft position of the balljoint on the cast arms versus the stamped arms has been shown to be different, and they have to be in order to alter the castor of the later cars. There's pictures of a tracing on paper showing the difference. Recently somebody also brought up that the holes in the cast arms do have a tolerance and can vary from arm to arm.

[zin]

I like Rich's plates, alot, but for now it's j/y upgrades which the arms seem to be a good candidate, though I think I'll try modifying the bar rather than replace it, as I'm enjoying the handling an 1 1/8" bar provides, unless I find a cast version, but I'm not holding my breath on that one!

Disappointing to hear the cast arms seem to have sloppy tolerances, I'll have to look closer than normal so as to be sure they are a good, matched pair...

Thanks for the Intel guys!

Mike

[Force Fed Mopar]

You mean vertically, correct? The fore/aft position of the balljoint on the cast arms versus the stamped arms has been shown to be different, and they have to be in order to alter the castor of the later cars. There's pictures of a tracing on paper showing the difference. Recently somebody also brought up that the holes in the cast arms do have a tolerance and can vary from arm to arm.

All I know is that my wheels did not change in fore/aft position between stamped '89 Lebaron arms and cast '93 Shadow arms. This was on my '87 Shelby Z that I swapped a '89 dual-pivot k-frame into.

[Reaper1]

Yup, and I've heard of others having good luck as well as having the same situation I had. When I swapped in '93 Shadow K-frame, cast arms, and knuckles into my 1990 Daytona, the wheel clearance did change. The same happened when that set-up got moved to my 1988 Shelby Z. Once I swapped back to the stamped arms the problem went away.

[Force Fed Mopar]

Weird...

[rbryant]

Disappointing to hear the cast arms seem to have sloppy tolerances, I'll have to look closer than normal so as to be sure they are a good, matched pair...

Thanks for the Intel guys!

Mike

Mike,

I think they did it on purpose to add caster rather than it being a tolerance issue. Just look at where the hole was machined for the ball joint. If you want one with more caster look for one where the ball joint was drilled in the very front of the boss rather than the middle. This can add almost 3/8" or so from my measurements. I think I posted pictures of it somewhere.

If you want to adapt the stamped swaybar then you should be able to do it with rod ends. Either by drilling and tapping the end of the bar or by welding a threaded piece to them. I did actually convert a few cast bars to work with rod ends on the stamped bars when I did the dual pivot lbody kframe work.

-Rich

[zin]

Mike,

I think they did it on purpose to add caster rather than it being a tolerance issue. Just look at where the hole was machined for the ball joint. If you want one with more caster look for one where the ball joint was drilled in the very front of the boss rather than the middle. This can add almost 3/8" or so from my measurements. I think I posted pictures of it somewhere.

If you want to adapt the stamped swaybar then you should be able to do it with rod ends. Either by drilling and tapping the end of the bar or by welding a threaded piece to them. I did actually convert a few cast bars to work with rod ends on the stamped bars when I did the dual pivot lbody kframe work.

-Rich

Thanks for chiming in Rich, I was hoping you would. And I'm happy to hear that there is some caster to be had with the cast arms, which is really the only reason I'm interested in them, otherwise they are way too heavy!

What I'd really like to do, and hopefully will is install your caster/camber plates so I things can be set "properly"... whatever that turns out to be!

Mike

[cordes]

Have to use the cast swaybar.



Balljoint is in the same place regardless of whether you use stamped or cast arms. Maybe vans have it located further forward in the arm, but the vertical position is determined by the knuckle.

You're right. I wasn't thinking. It's the lighter weight of the stamped arms that cause me to stick with them.

[Reaper1]

I thought someone weighed them and there was only 1# difference between them?

[rbryant]

I thought someone weighed them and there was only 1# difference between them?

Stamped arms were 2lbs, 4oz lighter each when I weighed them.


Info added to the KC article: http://www.turbo-mopar.com/forums/kn...01&redirect=no

I did have a friend who took a step drill/hole saw to the cast arms in some strategic locations and removed some weight from them but don't do that unless you know what you are doing. The steering stops could be removed with no major concerns to save some weight since the wheels will stop when they hit the transmission anyway.

-Rich

[Force Fed Mopar]

Cast arm setup rides better.

[zin]

Holy crap! They are actually lighter?!! For some reason I had the distinct impression that they were about that much heavier! I would have made the switch some time ago had I had my facts straight!

Mike

[cordes]

Holy crap! They are actually lighter?!! For some reason I had the distinct impression that they were about that much heavier! I would have made the switch some time ago had I had my facts straight!

Mike

He mistyped that. If you read the KC article he states that the stamped arms are 2.25lbs lighter.

[Pat]

I am positive cast is heavier.