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post #7636 of 8099 Old 11-03-2014, 07:18 AM Thread Starter
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Glad to hear you dad is doing better. Outside food should help immensely!
I agree...and the improvement continues, so that's even better news.

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You don't call, you don't write. Shenanigans.
Hey...you're the one that vanished with even more alacrity than I usually exhibit...but since we're not pointing fingers, here, I hope you - and everyone, for that matter - will accept my apologies for being entirely too busy with...well, everything...for quite some time, now.


If it's worth doing, then it's worth overdoing.

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post #7637 of 8099 Old 11-03-2014, 07:54 AM Thread Starter
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Today's Jeeping: Can someone PLEASE answer these questions for me: Why don't link bridges/trusses hug the axle tubes and housings? Why do most of them seem obtrusively large and stand off from the housing itself? Does nobody make something that wraps the differential a bit closer than the common offerings? ???

If it's worth doing, then it's worth overdoing.

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post #7638 of 8099 Old 11-03-2014, 10:06 AM
LA-Sahara
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Not sure what you're looking for, but my Barnes4wd bridge is only about a 1/2" above my 44. And can always be cut down dome more.
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post #7639 of 8099 Old 11-03-2014, 10:11 AM
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If you look at your stock axle, the lower control arms are mounted below axle center line. Most people raise them to axle center line for better clearance. That means the uppers have to move up. Also, axle link separation is supposed to be around 25% of tire diameter, so big boy tires require even more separation. Hence, tall trusses. Of course tall truss + "Low COG" = cutting the floor. Also some trusses are "generic", as in can be used for a variety of diffs.

As said, you can always cut yours down, but that defeats some of the purpose of buying one.


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post #7640 of 8099 Old 11-03-2014, 11:51 AM
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Quote:
Originally Posted by Sundowner
Today's Jeeping: Can someone PLEASE answer these questions for me: Why don't link bridges/trusses hug the axle tubes and housings? Why do most of them seem obtrusively large and stand off from the housing itself? Does nobody make something that wraps the differential a bit closer than the common offerings? ???
my BTF truss hugs my diff really well, the included diff cover is really beady and it bolts the the truss
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post #7641 of 8099 Old 11-04-2014, 07:22 AM
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Quote:
Originally Posted by Sundowner
Hey...you're the one that vanished with even more alacrity than I usually exhibit...but since we're not pointing fingers, here, I hope you - and everyone, for that matter - will accept my apologies for being entirely too busy with...well, everything...for quite some time, now.
What can I say, I hate almost everybody here

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post #7642 of 8099 Old 11-04-2014, 08:17 AM
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I've had the same questions about trusses lately. I'm pretty much decided on the Barnes 44 truss for the rear and Clayton for the front. Seems like the Barnes would be the easiest to modify if you want it to sit lower since it doesn't tie in to the diff cover.

Savvy 3" Springs, 4 Link rear with outboarded shocks, Savvy UnderArmor, 255/85R16 Toyo M/T


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post #7643 of 8099 Old 11-04-2014, 10:06 AM
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Quote:
Originally Posted by clintrivera View Post
If you look at your stock axle, the lower control arms are mounted below axle center line. Most people raise them to axle center line for better clearance. That means the uppers have to move up. Also, axle link separation is supposed to be around 25% of tire diameter, so big boy tires require even more separation. Hence, tall trusses. Of course tall truss + "Low COG" = cutting the floor. Also some trusses are "generic", as in can be used for a variety of diffs.

As said, you can always cut yours down, but that defeats some of the purpose of buying one.
Is the 25% of tire diameter a matter of strength, or geometry?

-Scuzz

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post #7644 of 8099 Old 11-04-2014, 12:17 PM
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Originally Posted by CEScuzzy View Post
Is the 25% of tire diameter a matter of strength, or geometry?

-Scuzz
A tire is basically a large lever trying to force the axle to twist forward and backward. The control arms stop it. The larger the tire, the more force applied to the control arms and brackets, truss, etc.


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post #7645 of 8099 Old 11-04-2014, 12:26 PM Thread Starter
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Okay...roughly in order...

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Originally Posted by LA-Sahara View Post
Not sure what you're looking for, but my Barnes4wd bridge is only about a 1/2" above my 44. And can always be cut down dome more.
My main goal with a link bridge is to just give myself a good mounting surface for the axle end of the driver's side upper link...but I also want to keep the axle looking as "factory" as is possible; I don't have any sort of good reason for that, other than wanting to have a sleeper-esque HP44 front. Given my preferences and with cost as no option, I'd make a truss that essentially followed the contour of the housing and left very little room for daylight to show through; the main bridge would be 3/8" steel with a bend or four in it - actually it would probably have exactly four - and I'd weld on some skirting pieces in order to clean up the look, front and rear. End result: ultra-low-profile link bridge that can't easily be seen.

Quote:
Originally Posted by clintrivera View Post
If you look at your stock axle, the lower control arms are mounted below axle center line. Most people raise them to axle center line for better clearance. That means the uppers have to move up. Also, axle link separation is supposed to be around 25% of tire diameter, so big boy tires require even more separation. Hence, tall trusses. Of course tall truss + "Low COG" = cutting the floor. Also some trusses are "generic", as in can be used for a variety of diffs.
I'm going to keep my lowers about 1" below the centerline on the axle end; any higher and all of my numbers start to get...weird. I hadn't really thought about link separation in terms of tire diameter, but it seems to make sense to me now that I consider it in that way. That would be a good starting point for that portion of the suspension's design.

Quote:
Originally Posted by clintrivera View Post
As said, you can always cut yours down, but that defeats some of the purpose of buying one.
Exactly; if I'm going to modify something to any significant degree, I'd be better off getting exactly what I want custom-made...or making it myself.

Quote:
Originally Posted by 84jeepcj7rock View Post
my BTF truss hugs my diff really well, the included diff cover is really beady and it bolts the the truss
I like the way the BTF stuff bolts in; that's something to consider.

Quote:
Originally Posted by srfnfly227 View Post
I've had the same questions about trusses lately. I'm pretty much decided on the Barnes 44 truss for the rear and Clayton for the front. Seems like the Barnes would be the easiest to modify if you want it to sit lower since it doesn't tie in to the diff cover.
The Clayton is about the lowest-profile that I've found so far, but it's only listed for the TJ44...not an HP44. Regardless, Jankoid has assured me that it will, indeed, work on the latter axle...so it's in contention as either a solution or a starting point.

Quote:
Originally Posted by CEScuzzy View Post
Is the 25% of tire diameter a matter of strength, or geometry?
Link separation is more about transfer of force; that's the easiest way to generalize it.

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Originally Posted by spyder6 View Post
What can I say, I hate almost everybody here
Well, I'm glad you showed back up, regardless.

If it's worth doing, then it's worth overdoing.

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post #7646 of 8099 Old 11-04-2014, 01:00 PM
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Quote:
Originally Posted by clintrivera View Post
A tire is basically a large lever trying to force the axle to twist forward and backward. The control arms stop it. The larger the tire, the more force applied to the control arms and brackets, truss, etc.
Strength then, gotcha.

Quote:
Originally Posted by Sundowner View Post
Link separation is more about transfer of force; that's the easiest way to generalize it.
I expected something along those lines. I used the word strength to refer to the system's ability to withstand and redirect torque through the control arms (perhaps a hasty generalization to sum that up in one word.) Longer mount brackets allow the control arms to exert more resistance to the torque placed upon the system by the tires.

If I had more time, I'd run the numbers.

-Scuzz

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post #7647 of 8099 Old 11-04-2014, 01:26 PM Thread Starter
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Strength then, gotcha.
Sort of...

Quote:
Originally Posted by CEScuzzy View Post
I expected something along those lines. I used the word strength to refer to the system's ability to withstand and redirect torque through the control arms (perhaps a hasty generalization to sum that up in one word.) Longer mount brackets allow the control arms to exert more resistance to the torque placed upon the system by the tires.
...and in turn, take more load, themselves. In the world of suspensions, nothing is free and everything is a compromise...and often, it's a compromise between opposing forces. I'm not doing anything terribly radical with my suspension design - it's actually nothing more than the stock geometry warped into a better configuration for larger tires - and there's a very good reason for it; past a certain point the compromises start stacking up and building on each other. It's not limited to the first-order effects, either; much as Clint mentioned - and as we've discussed before - there are second- and third-order impacts. Floors may need cutting, frames may get in the way, engines may have to be relocated, and the suspension itself may have to be partially redesigned in order to keep from getting in its own way...and that's just the start of it.

If it's worth doing, then it's worth overdoing.

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post #7648 of 8099 Old 11-04-2014, 01:44 PM
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You're staying 4 link with track bar front? Or 3 link with track bar?
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post #7649 of 8099 Old 11-04-2014, 01:46 PM
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Originally Posted by Sundowner View Post
Sort of...



...and in turn, take more load, themselves. In the world of suspensions, nothing is free and everything is a compromise...and often, it's a compromise between opposing forces. I'm not doing anything terribly radical with my suspension design - it's actually nothing more than the stock geometry warped into a better configuration for larger tires - and there's a very good reason for it; past a certain point the compromises start stacking up and building on each other. It's not limited to the first-order effects, either; much as Clint mentioned - and as we've discussed before - there are second- and third-order impacts. Floors may need cutting, frames may get in the way, engines may have to be relocated, and the suspension itself may have to be partially redesigned in order to keep from getting in its own way...and that's just the start of it.
I know this has probably crossed the conversation before, but if you're introducing modifications this extensive, why not just go straight to some manner of tube buggy? Not that I disapprove of your philosophy here, but by the time you complete this design, it seems to me that you will be nearly there already.

That said, I understand that you want to do it, and that's all that really matters here.

-Scuzz

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post #7650 of 8099 Old 11-04-2014, 01:56 PM
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The conversation is getting interested again. I like learning.
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