Opinions on offset rear control arms
#51
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Re: Opinions on offset rear control arms
since we are on the topic of aluminum, i was looking at the prices of 6061-t6, and it would run about 165 bux for a 4' long piece, 4"x6", not really as bad as i would have thought. The aluminum would be the item of last resort, like sonix said, there is always steel, but the weight. The aluminum would be sweet, and i know a very good machinist who can make them. As far as the fatigue rate, people on here run aluminum control arms made of 1"solid and they seem fine, would the aluminum fail with just a compression load?
Anyway, i have to wait till next week to see what Spohn has to say, and we will go from there.
Anyway, i have to wait till next week to see what Spohn has to say, and we will go from there.
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Re: Opinions on offset rear control arms
$165 for SOLID 4"x6"x48", or square/round tube? Seems low for solid (but I haven't dealt with any since '96/'97, and high for tubular.
#53
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Re: Opinions on offset rear control arms
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Re: Opinions on offset rear control arms
I was going to build me one 1 piece billet valve covers. Milled out of a solid piece. Sure, it woulda been a HUGE waste of material, but I wouldn't have had to pay for the machine time. I coulda just come in early, late, or a Saturday to do it, or if another machine was idle, I coulda used it. That's how I milled the derby Camaro. I used an idle machine!
Makes me wanna build some 1 piece ones now. Imagine having WS6 or GTA, or Z20 or FIREBIRD or CAMARO, either machined INTO the top, or the excess material being machined off, leaving them "embossed"!
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Re: Opinions on offset rear control arms
If you really want to build your own try using flat stock and tracing the basic shape to it making 2 pieces, for the top and bottom, take to more pieces that are cut to the height wanted and longer to accomodate the bends, then weld all pieces together to basically create a box. Hopefullly this makes some sense to a few people. I will try and draw up exactly what I am talking about.
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Re: Opinions on offset rear control arms
If you really want to build your own try using flat stock and tracing the basic shape to it making 2 pieces, for the top and bottom, take to more pieces that are cut to the height wanted and longer to accomodate the bends, then weld all pieces together to basically create a box. Hopefullly this makes some sense to a few people. I will try and draw up exactly what I am talking about.
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Re: Opinions on offset rear control arms
the pieces that are standing on end would not be all the way to the outside, move them inboard ~ the width of your weld fillet (3mm). BTW how much are you planning on "beating" on the car...ie...drag racing, autocross, or just a show/go toy?
#59
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Re: Opinions on offset rear control arms
im trying to use a rod end on one side, so a boxed design isnt really where im heading.
Its a street car, built to handle and may see some autox in the future
Its a street car, built to handle and may see some autox in the future
#60
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Re: Opinions on offset rear control arms
Steve over at Spohn told me he was planning to start these things yesterday, so thats good news. I dropped the wheels off at the Wheelworks to be widened, and should have them back late this week, then i can pickup the tires and start cutting, should keep me busy for a little while. Its just a shame i need to pull out the rear interior again.... I guess practice makes perfect
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Re: Opinions on offset rear control arms
I can't believe how long this thread is. I autocross and have been wondering what it would be like to have fat tires like that on my car but wow... thats a lot of work to get an extra inch of rubber to the ground (two inches total right? 1in for each tire?). I don't know much about the forces that would be applied to the LCA, but wouldn't it want to twist any time you hit the gas? I know thats why you want to have the rod ends, but I would think it would still want to twist way more than a normal straight LCA if you would accelerate out of a turn.
Anyway, I cant wait to see it installed.
Anyway, I cant wait to see it installed.
#62
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Re: Opinions on offset rear control arms
i dont think they would want to twist, by the design, just looking at it, if any movements would occur it would be bending inboard, but its such a short piece that i dont think it will happen.
It is a bit of work but, but i get bored in the winter time, my mind starts wandering , and things like this happen....
I cant wait to see what steve comes up with for the final piece
It is a bit of work but, but i get bored in the winter time, my mind starts wandering , and things like this happen....
I cant wait to see what steve comes up with for the final piece
#63
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Re: Opinions on offset rear control arms
I got a call from Steve Spohn to day, and the arms are done! just need to be powdercoated, and i should have them next week. He seemed very interested in them and mentioned that he may use the design for a catalog item, so thats pretty cool . Cant wait to see what he came up with and see if they fit like they are supposed to.
#64
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Re: Opinions on offset rear control arms
they showed up today and here they are, they even fit
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Re: Opinions on offset rear control arms
Hmmmm....I'd prefer to see the 2 tubes attached, then a plate over the "valley" boxing them together, than rely on the 2 curved tubes touching.
With such big tires, those points are gonna getting a lot of stress from launches and cornering.
Those may be perfectly fine. But in my building experience, I wouldn't trust those FULLY.
My
With such big tires, those points are gonna getting a lot of stress from launches and cornering.
Those may be perfectly fine. But in my building experience, I wouldn't trust those FULLY.
My
#66
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Re: Opinions on offset rear control arms
ick, scary !!!
you wouldnt catch me with those on my car !
good luck with that, and i hope it lasts
you wouldnt catch me with those on my car !
good luck with that, and i hope it lasts
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Re: Opinions on offset rear control arms
Please explain to me why you can't use square or rectangular tubing and rod ends.
#68
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Re: Opinions on offset rear control arms
ive never heard of a square tubing adapter .
All i know is, the guy who built these things builds suspension and chassis parts for a living and saw no issues with strength with the design. I may be naive (spl), but that gives me some comfort in their construction. I'll just have to keep an eye on them and see how the hold up
All i know is, the guy who built these things builds suspension and chassis parts for a living and saw no issues with strength with the design. I may be naive (spl), but that gives me some comfort in their construction. I'll just have to keep an eye on them and see how the hold up
Last edited by //<86TA>\\; 02-06-2008 at 10:18 PM.
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Re: Opinions on offset rear control arms
ive never heard of a square tubing adapter .
All i know is, the guy who built these things builds suspension and chassis parts for a living and saw no issues with strength with the design. I may be naive (spl), but that gives me some comfort in their construction. I'll just have to keep an eye on them and see how the hold up
All i know is, the guy who built these things builds suspension and chassis parts for a living and saw no issues with strength with the design. I may be naive (spl), but that gives me some comfort in their construction. I'll just have to keep an eye on them and see how the hold up
#70
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Re: Opinions on offset rear control arms
I truly hope you do not have problems with these ever but even if Steve made them (as opposed to myself) I would not use them on my car
Make sure you post pics when they are on the car! They still look nice
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Re: Opinions on offset rear control arms
They don't look strong, but sometimes your eyes don't tell the whole story.
If Spohn himself is willing to brand it with his name, knowing you frequent forums, knowing you are fully willing to post pictures of a destroyed Spohn product and the carnage that happened to your car - i'm guessing he has a decent idea how strong that will be.
If Spohn himself is willing to brand it with his name, knowing you frequent forums, knowing you are fully willing to post pictures of a destroyed Spohn product and the carnage that happened to your car - i'm guessing he has a decent idea how strong that will be.
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Re: Opinions on offset rear control arms
it looks like using off the shelf double rod ended offset LCAs would have given you essentially the same offset and been stronger. I wonder how well those will live with potholes and everything else a street car will encounter.
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Re: Opinions on offset rear control arms
The only off-the-shelf offset ones, that I've seen, only give about 1/8" offset. Not a couple of inches like his.
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Re: Opinions on offset rear control arms
I know it would be expensive but. I would like to see the same shape made out of one bent pice of tube. It can be done just not on a standard bender. Or one piece billet LCA. Like this but with the curves.
#76
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Re: Opinions on offset rear control arms
as for the off the shelf spherical ended offset arms, they dont have quite enough clearance, the tire will at least touch them, things are very tight in there.
actually, xpndbl3, you have those arms on you car dont you? when you get a minute and want to make a measurement for me, what the measurement form the face of the rotor/drum to the arm?
the negative vibes are unreal......
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Re: Opinions on offset rear control arms
Sign me up for a set if they work. I bet they will!
I would love to tuck my 315's a bit more.
I would love to tuck my 315's a bit more.
#78
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Re: Opinions on offset rear control arms
found this while searching, search does work!
Any way, i've beaten on these arms pretty hard for almost 2 years now with no issues at all. Still dead straight. Working like a charm.
Any way, i've beaten on these arms pretty hard for almost 2 years now with no issues at all. Still dead straight. Working like a charm.
#80
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Re: Opinions on offset rear control arms
yes, and? 1 year, 9 months
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Re: Opinions on offset rear control arms
I'm suprised at the negatives as well, I plan on doing the same to fit 335s as well. The welds will be as strong as, if not stronger than the tubing IMO. I'll be using ER70S tig rods, which have a 70,000 PSI tensile strength. With the welds on both sides of where the tubing meets, it's basicially 1" thick solid weld. When welding 1/2" solid plate for my AWS certification, we grind a "V" into the plate and weld in multiple passes, weaving one bead into another (MIG). we then then bend the plate at the welds 180* on a 3/4" radius in either direction, and if it was gonna fail, it would fail then. And when bent, it's almost impossible to see the actual weld area without an untrained eye. You are essentially creating 2 "V's" welding it solid. Capping the ends of the tubing pretty much eliminates the weakest portion of the design. I'm just the welder/machinist, so I have had the Mechanical Engineer at work run the modeling to check my theory, he said in typical suspension cycling, assuming I don't put it in a wall, it'll still be less likely to fail than stock.
#82
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Re: Opinions on offset rear control arms
Searching around again and dug this back up.
its 2015 and I'm still alive and these arms are still holding up well.
amazing how time flies though, I can't believe its been almost 7 years
its 2015 and I'm still alive and these arms are still holding up well.
amazing how time flies though, I can't believe its been almost 7 years
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Re: Opinions on offset rear control arms
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Re: Opinions on offset rear control arms
I asked about 5 months ago if I could get a set, spohn said no problem. I did not order them since I don't need them yet, but they say they have the drawings to make sets if need be.
#86
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Re: Opinions on offset rear control arms
It's great to see a long term evaluation on a product such as this. Good Job!
Where are all the naysayers now? If more members would post long term results the community would be better off than many members reporting on the same product in the short term. Great to hear those worked so well for you and am really surprised Spohn didn't catalog them.
#87
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Re: Opinions on offset rear control arms
Sounds like he can make them real easy, prolly such a low demand that it doesn't pay to make them and have them sitting though. That's cool that he keeps schematics for things to build to order like this though.
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