Long arms conversion

[ponyracer1]

What do you guys think of these?

http://www.suicidedoors.com/4-LinkRoundAdjBarwithSuperPivot.php

I know for lowers you want 2" not 1.5 but for the money do you think they would stand up to some mild abuse and alot of road miles??

I have the re 5.5 short arm kit now and I'm thinking of changing to a radius arm set up, modding the re uppers to work.

Thanks

[vetteboy]

Looks decent enough, I guess...and 1.5" x .25" is good enough for the street.

Two things though:

For a radius arm setup, you want the flex joint on the frame end. The axle lower control arm mounts have a 2-5/8" spacing. They don't offer bushings in that spacing, so unless you put the flex joint on the axle (not recommended) then you're kinda stuck with figuring out how to fit a larger bushing in the axle mount.

Also...what are you doing for a crossmember? Is it really going to be worth it to maybe save some time by buying arms, only to be limited by them in your overall design?

[xDUMPTRUCKx]

I like the part in the ad that says if they bend they will replace them for free.......

[ponyracer1]

I'm looking at doing some of these, regardless of the arm choice. I'll prob do the poly's chromo arms as well. That way I'd NEVER have to worry about them.

http://www.polyperformance.com/shop/product.php?productid=699&cat=158&page=1

Anyone using these?

I figured this way I can make the arms independedt of the skid. That's the one thing I hate about T&T's set up.

[Ghost]

I could be wrong but I would think that they would rip the thin sheet metal. Will you be mounting them on a plate then welding it to the unibody? I hope someone chimes in on this bc I really dont "know" but that is what I would guess.

[vetteboy]

I'm looking at doing some of these, regardless of the arm choice. I'll prob do the poly's chromo arms as well. That way I'd NEVER have to worry about them.

http://www.polyperformance.com/shop/product.php?productid=699&cat=158&page=1

Anyone using these?

I figured this way I can make the arms independedt of the skid. That's the one thing I hate about T&T's set up.

You're not planning on just welding those to the unibody rails, are you?

Where were you planning on putting them to make them seperate from the crossmember? Any closer to the front axle and you're really eliminating any advantage of the setup (you want the arms to be as long as possible). Any longer...welll...there's a crossmember in the way. That's why it usually ends up being part of the same piece.

It's really not that big of a deal to remove that stuff if you have to get to the transmission, which doesn't really happen too often anyway.

[Phil]

It's really not that big of a deal to remove that stuff if you have to get to the transmission, which doesn't really happen too often anyway.

x2 100%

http://www.liracon.com/ron/post/intern03.jpg
http://www.liracon.com/ron/post/intern08.jpg
http://www.liracon.com/ron/post/intern09.jpg

[ponyracer1]

You're not planning on just welding those to the unibody rails, are you?

Where were you planning on putting them to make them seperate from the crossmember? Any closer to the front axle and you're really eliminating any advantage of the setup (you want the arms to be as long as possible). Any longer...welll...there's a crossmember in the way. That's why it usually ends up being part of the same piece.

It's really not that big of a deal to remove that stuff if you have to get to the transmission, which doesn't really happen too often anyway.


Well after some measuring tonight I can use the full 36" peice of the chromo. As far as the "frame" goes, I've plated the outside and the bottom with 3/16, I'll clean off the inside of the frame and plate it to the sheet metal with edge welding and plug welds. I figure a 24 inch piece of plate will distribute the load enough so no problems arise.

Thanks for the thoughts

[ponyracer1]

x2 100%

http://www.liracon.com/ron/post/intern03.jpg
http://www.liracon.com/ron/post/intern08.jpg
http://www.liracon.com/ron/post/intern09.jpg

Is it me or does this last pic look painful????

Well I made a nice list with poly, .250 wall dom, jonny joints, rubber bushes etc, now they won't send it to me!! They WILL NOT deal with USPS as they have been burned in the past. Anyone know of any other good suppliers for fab parts? Or do I have to do the send it to family, they send it to me crap??

Thanks

[Danno]

what's wrong with FedEx or UPS? They all ship to Europe. Or you trying to ship via the APO which in that case it goes to the USPS and then turn it over to FedEx to ship (no joke!).
You guys flying anything good out of Mildenhall?

[Danno]

[QUOTE=Phil]x2 100%

How in the heck did you break the bell house?! I'd really like to know! Whew!:wierd:

[Kittrell]

You guys flying anything good out of Mildenhall?

I have a buddy stationed there IIRC, mechanic. Keeps them birds in the air

[ponyracer1]

what's wrong with FedEx or UPS? They all ship to Europe. Or you trying to ship via the APO which in that case it goes to the USPS and then turn it over to FedEx to ship (no joke!).
You guys flying anything good out of Mildenhall?


I have a buddy stationed there IIRC, mechanic. Keeps them birds in the air






I checked UPS, sure they'll ship it FOR $375 DOLLARS!!!!! The order is only $399!!!!

Na nothing good ever comes out of Moldyhole. Just a bunch o heavies.

[ponyracer1]

Is there any benefit to using this type of set up in a radius arm suspension?

http://www.ruffstuffspecialties.com/catalog/antiwraptraction-plates-p-165.html

Would this help or hurt you as far as flex and tearing up bushings vs using the stock mounts? What about using the above with these bushings?

http://www.ruffstuffspecialties.com/catalog/bushed-sleeve-p-148.html

Luckily I just got 3 peices of 2" .250 wall DOM locally so that's one less this to ship!!

[Russ Pottenger]

x2 100%

http://www.liracon.com/ron/post/intern03.jpg
http://www.liracon.com/ron/post/intern08.jpg
http://www.liracon.com/ron/post/intern09.jpg
Phil, its gettin close to Christmas. Gona put a good word into Santa for ya, for some rail protection. :D

[crasy1_69]

looks like it tooooooooooooo late for rail protection.

[ponyracer1]

OK, after reading on here for 6 hrs yesterday I've got the design narrowed down. It seems to me that the easiest design that works the best is a radius arm 3 link. Looked at the URF 3 link design but there's alot more design input into that type, (read-trial and error) esspecially for a first time suspension builder.

Can you guys look at this and see what you think? It's going under a DD with 35's and a dana 30.

1. Arms, 2' .250 wall straight.
2. Ends, JJ at all 6 intersections
3. Will be plating the frame and mounting the lowers inboard of the frame in high clearance mounts independent of the Xmember.
4. Removing the stock lower axle mounts, replacing them with flush mounts on the rear/bottom of axle.
5. Removing the stock pass side upper mount, replacing it with a braced mount, prob. the ones sold by poly perf.
6. Lowers will be between 36-40 inchs long.

Now here's my questions, I know in this design there's alot of force on the upper so I'm using the .250 wall for that as well.

1. Any problem going that thick on the upper? (It's what I have, also have dom 1 3/4 .120 wall)

2. How high does the upper mount need to be (ballpark) for this design. I read 9" of vertical seperation is a good place to start. Does that still hold true?

3. How far back would you mount the upper on the lower arm? As far back as possible and still clear everything or closer to the front? I read the flatter the angle the better which leads me to think farther back and raise it up as high as possible in the mount.

4. How do you think the street manners will be on this design? Should be similar to a standard radius arm set up right?

Thanks guys

[vetteboy]

5. Removing the stock pass side upper mount, replacing it with a braced mount, prob. the ones sold by poly perf.

Are you only using one 'upper'? If so, why bother doing anything with the passenger side?

6. Lowers will be between 36-40 inchs long.

Still curious how you're going to fit this past the crossmember without stretching the wheelbase up front. Don't forget the fuel lines and brake lines run inboard of the frame rails there as well, and it's not a flat surface to begin with (there's a pinch seam that comes out perpendicular to the frame rail).

Also you need to consider interference from the frame rails at the area where the old LCA mount used to be. I had this problem, and my mounts were even more triangulated than yours, and lower.

Look at the area right where the frame rail starts to curve up to the spring mount:

http://www.phatserver.net/~chris/la/lafinal%20018.jpg

That's not at full stuff, and like I said, you can see how much lower those arms mounted. The axle mounts are not a straight shot from the LCA bracket, they're triangulated outwards, which is why this clearance becomes an issue.

A little different view here:

http://www.phatserver.net/~chris/la/lafinal%20015.jpg

Now here's my questions, I know in this design there's alot of force on the upper so I'm using the .250 wall for that as well.

1. Any problem going that thick on the upper? (It's what I have, also have dom 1 3/4 .120 wall)

Nope. Use the thicker stuff and you'll be fine.

2. How high does the upper mount need to be (ballpark) for this design. I read 9" of vertical seperation is a good place to start. Does that still hold true?

No. Axle mount vertical seperation on a radius arm suspension changes nothing as far as dynamic response. What it DOES change is the amount of force the 'upper' link will experience, and also how much binding there will be when articulating (not an issue with only 1 upper). Typically mounting the upper to the factory UCA mount on the axle gives decent results.

Changing the vertical seperation on the axle has a much larger effect on 3- and 4-link setups, where the instant center doesn't remain constant and there are a lot more considerations to be made for pinion angle change etc.

3. How far back would you mount the upper on the lower arm? As far back as possible and still clear everything or closer to the front? I read the flatter the angle the better which leads me to think farther back and raise it up as high as possible in the mount.

Correct. The longer you can make that upper, the less binding and the less leverage on the upper link. The specific angle of the upper link in a radius arm setup again has no effect on the actual dynamics of the thing - that is more specific to the 3- and 4-link setups as mentioned above. However keeping the main radius arm (the lower) flat is highly beneficial.

4. How do you think the street manners will be on this design? Should be similar to a standard radius arm set up right?

Really depends on a few things. With a single upper you're doing the right thing in not using bushings, as this will keep the axle rotation during braking at zero. It also depends a lot on the angle of the arms - radius arms work best when they're as flat as possible, and if you're trying to tuck them up inside the frame rails, you may end up with some angle on there depending on lift height. What you'll see from that is increased anti-dive, which can give an interesting feel during hard braking (the front won't dive as much as you're used to) and also lead to increased unloading when climbing steep hills (= loss of traction under the front wheels, more weight transfer to the rear, less steering control, more likely to backwards roll). Again, this depends on your specific angle and it's likely that it'll be 'decent', and it's a simple solution that will help increase articulation and improve ride quality over short arms...but there's a reason why most guys on here graduate away from radius arm configurations.

My opinions on the setup I built/ran - it worked. The brake dive thing took some getting used to and got a little squirrelly in situations where I had to maneuver during heavy braking. The front end did tend to unload while climbing (this is REALLY obvious in videos I have of it) but the shocks were too short to allow full travel at the time, so that kept it under control (same thing a limiting strap would do, but less.....elegant?). Crossmember hung too low but I knew this when I built it and the whole thing was really a design experiment anyway, as it was the first one I had built.

Take a look/search for Timmay's recent buildup - he just did a nice radius arm setup on his DD XJ.

Does that all make sense?

[Phil]

Are you only using one 'upper'? If so, why bother doing anything with the passenger side?
Running the single upper on the passenger side reduces any clearance issues for the front driveline.
Still curious how you're going to fit this past the crossmember without stretching the wheelbase up front. Don't forget the fuel lines and brake lines run inboard of the frame rails there as well, and it's not a flat surface to begin with (there's a pinch seam that comes out perpendicular to the frame rail).

Also you need to consider interference from the frame rails at the area where the old LCA mount used to be. I had this problem, and my mounts were even more triangulated than yours, and lower.
You can move the brake and fuel lines, and remove part of the pinch seam if necessary. I don't have framerail clearance issues, and my mounts are even more triangulated than yours, and higher. My lowers are 40" long. You can see how we did my transmission mount and arm mounts in my pictures.

[GSequoia]

Phil, its gettin close to Christmas. Gona put a good word into Santa for ya, for some rail protection. :D

Rails are soooo last year.

The boy needs to boatside it.

[ponyracer1]

WOW!! Thanks for the info guys, I may move the rear lower mount to the edge or just below the frame rail if needed to keep the lower as flat is possible.

Thanks again for the info. I'll post up again when all the ends turn up and the sparks start flying.

[vetteboy]

Running the single upper on the passenger side reduces any clearance issues for the front driveline.

Alright, I can see that I guess, although I didn't have any driveline clearance problems with mine. I would recommend doing a truss or something though if this is the case.

You can move the brake and fuel lines, and remove part of the pinch seam if necessary. I don't have framerail clearance issues, and my mounts are even more triangulated than yours, and higher. My lowers are 40" long. You can see how we did my transmission mount and arm mounts in my pictures.

Having the arms be more triangulated would help the clearance, not hurt it, no? Are you still on a D30? On the 3-link I'm doing now, the lowers are inboard about 3" on each side from the frame rails, mounted up even height-wise with the inside of the frame, and go out to the outer ends of a D60 front, and it's looking like I'll still have some small issues at that same area.

http://www.phatserver.net/~chris/XJbuild/100306/spring3.JPG

Guess it depends also on total lift height too. I'm trying to stay at around 4.5 - 5" or so.

[vetteboy]

OK, I see how you did yours...

http://img101.imageshack.us/img101/2554/pdrm08600nz.th.jpg (http://img101.imageshack.us/my.php?image=pdrm08600nz.jpg)

(I like that design, by the way)

but pulling the arms in close like that will definitely help clear the frame rails. It seems like Ponyracer1 wants to mount them directly off the inside of the frame rail, putting them a few inches further apart on each side and making it harder to clear the rails.

[ponyracer1]

Well the original ideas will/may change once I actually start mounting stuff up and flexing it to check clearance. My goal was to mount them to the frame rail so the cross member could be removeable. But then again, how often do you need to pull your crossmember?? Thanks for all the info and pics.

[vetteboy]

But then again, how often do you need to pull your crossmember??

Hopefully not often, because I'm totally screwed if I gotta do this again. :roll:

http://www.phatserver.net/~chris/XJbuild/092306/under2.JPG

[ponyracer1]

HAHA, holy god man that's nuts!! You've got more steel in your cross members than is in most import cars!!!

[vintagespeed]

I could be wrong but I would think that they would rip the thin sheet metal. Will you be mounting them on a plate then welding it to the unibody? I hope someone chimes in on this bc I really dont "know" but that is what I would guess.

Plate the framerail where you're going to weld them, and then weld them to the plate. Done deal.

The unibody isn't as weak as alot of webbies will tell you it is.

[Ghost]

Plate the framerail where you're going to weld them, and then weld them to the plate. Done deal.

The unibody isn't as weak as alot of webbies will tell you it is.
Umm well maybe you can explain to me why my factry LCA mounts ripped most of the way off? It is quite thin ty very much and I have been under there welder in hand fixing it! :sure: Oh yea I have some pictures but lost the digi! Go FIgure!

[vintagespeed]

Umm well maybe you can explain to me why my factry LCA mounts ripped most of the way off? It is quite thin ty very much and I have been under there welder in hand fixing it! :sure: Oh yea I have some pictures but lost the digi! Go FIgure!

Cause you smacked them on shit until they ripped off?

I said plate the framerail & then mount to it.

[Ghost]

Cause you smacked them on shit until they ripped off?

I said plate the framerail & then mount to it.
Nope actualy it was DW and an old heep!

[vintagespeed]

Nope actualy it was DW and an old heep!

Welp, I hate to argue something stupid so thanks for dragging me into it and ruining this guy's thread.

Anyway, it most likely had to do with your geographic location (ie: RUST) or some kind of previous damage. Death Wobble isn't going to rip off your control arm mounts off.

My Junk was hit while parked on the street by a Cadillac doing about 40-50mph. It tore the axle end CA mounts from one side of the tube, folded the other side over and moved the axle over about 2" by bending the trackbar and draglink, knocked the Jeep back about 10ft.

But it didn't hurt the frame end brackets at all. So I'm not buying your statement.