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Long travel front suspension


Rallyru
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I've read plenty of other "long travel" threads and they all seem to end in "the axle limits travel, without $$$ custom axles you wont achieve anything." Well lets say I had some high angle axles, what would limit travel then? I seem to remember a few threads about super beetle front struts for more travel. Did any tangible results ever come from this? image_zpscdjujqt4.jpeg

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Found the answer to my question in another thread. The axle hits the lower control arm mount. Lucky for me I'm still using the ea81 subframe witch has the control arm mount farther forward so the axle won't hit anything. So what else limits travel?

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There just isent any traval to be gained in the stock set up every thing is so short unless your going all custom your just chasing your tail you might gain an extra inch at best the selling point of those axles is that the joints are stronger 6 ball instead of 3 on the trans side and beafy slip yoke and something like 45* working angle or something crazy so if you did build a crazy custom set up they will work great and provide the extra traval if needed

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I think the angles are around 45 at the wheel and 40 at the trans or something close to that. I don't mind crazy full custom stuff. I like the challenge. I never expected anything stock to be a direct swap. I think even with a 2 inch lift the tie rods are pretty maxed out so that will also need to be addressed. I'll also need to look at how much angle the ball joints can take because that might also be an issue.

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If your lifting over 2" then you drop the crosmember to address those issues the stock control arms are short and will be the biggest limiting factor it wheel traval they swing in a ark the longer the arm the less of a ark in there line of traval the less of a ark you get the less stress on the componits and less binding stock arms travaling 6" moves the top or bottom of the tire in and out around 2" through out its swing thats where your binding come from in the stock set up longer arms reduce the stress because the same 6" of travel will have less in and out movement and your tire will traval in a straighter line and have less bump steer

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You got me thinking about this last night and i had some ideas use hyme joints on both ends of a rod conect one end directly to the lower ball joint and other to the cross member that would give camber adjustment to the system same on the radius rods i found some fox coilovers that would bolt to our top hats and on the bottom fabricate a base and spring perch to fit out ea knuckles and bolt the shaft in to that basicly inverting the shock the shocks i looked at had around 10" of traval for alittle over $300 a piece i also looked at rancho 9000s basicly the same but they only have a 5/8 shaft there only 110 each and would need to fab up a top mount im sure i could do it but again the biggest gain would be 4" of traval and most of that would be on the droop side and i dought any set up is gona reach the full 10" of traval but i could be wrong so this set up would cost around im guessing 500 to 1000 for miniscule gains you would be better off puting a solid axle in the rear way more articulation for the money spent and as a bonus you would have locker opptions and more parts availability and would increse the durability of the rig over all

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Part of the goal for doing this would be achieving more then 2 inches of suspension lift. I'd like to see how much I can get out of the "stock" control arms but lengthening the axle to accommodate longer control arms is possible. I guess it would help if I gave a little more info on my setup. I have a 4 inch SJR lift with the 3 inch transmission so the control arm and radio is rod at at the same level. I extended the radio is rod 1 inch, swapped to ea82 control arms, bent them back to meet the radio is rod, and extended the subframe 3/4 inch on each side.

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I'd rather stay away from solid axles. They just arnt my thing. If I wanted that I would just get a Toyota like everybody else out here in St Helens. How does the size of the Rancho compare to stock struts? The heim joints would also allow me to fine tune the caster.

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You dont need heim joints if you revise the radius rod mounting. The biggest problem with the stock suspension is a geometry problem rather than a component problem.First the radius rods pivot point is not linear with the control arm so the only amount of flex possible is what you can get by deforming the rubber bushings.Once you fix that the strut only has 4-6" of travel with most that being down travel.After that the next issue is the fact that the control arms mount outboard of the inner Cv axle joint  centerline,this causes axle plunge.With EA81 suspension 1.5-2" of suspension lift causes the CV balls to be rammed into the back of the inner DOJ cup,at max up travel the Balls are at the very outer edge of the DOJ cup.The CV axle being under compression is what kills EA81 CV axles with suspension lift.Ideally the control arms should pivot on an imaginary line that goes from the top of the strut through the middle of the inner DOJ,As long as the control arm pivots are on that line below the axles you wont have much axle plunge (+/- .25" vs +/-2").

 

Finally after all that is sorted out the steering rack pivots are also outboard of that ideal imaginary line so they induce alot of bumpsteer and toe as the suspension cycles after the narrow factory travel range.Finally,the tie rod and control arm ball joints will bind up at the extremes of travel.Once you fix all of that the CV axle is the problem,but by that point you will have over 12" of suspension travel.

 

 

I have been trying to address all those issues in the brat I am building but between work and plain old lazyiness its taking a while.

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Are those Heri axles?  Curious to see how they hold up when you start beating on them.

 

How much travel are you trying to get?

 

We got 11-12" of travel out of a custom built strut setup.  There are a lot of limitations beyond that unless you're making all new arms and links or making major body modifications/lift.

Edited by pontoontodd
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They are Surtrack/Trakmotive that I actually found on rockauto surprisingly. I have high hopes but low expectations. Last time I had some I blew them up within 100 miles but I believe that was my fault so Im giving them another try. Id be happy with anything in the 10-12 inch range. I would just like the front to be able to flex as much as the back. Care to divulge your strut recipe? Im quit intrigued.

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Full build thread:

http://www.ultimatesubaru.org/forum/topic/144953-long-travel-outbacks-or-making-subarus-faster-and-more-reliable-offroad/

 

The start of the long travel build starts on post 81:  http://www.ultimates...-4#entry1266961

Fairly current pictures of the long travel struts on post 218:  http://www.ultimates...-9#entry1307908

 

Reader's digest version, we made inverted struts for the front and rear.  It is a fair amount of work and expense.  If someone wanted to buy a set I'd probably have to charge about $5000.  You'll probably find this to be the case for any set of rally struts and springs that are well regarded.  The axles were sort of a limiting factor in droop, but various other things were binding up at that point also, it would take a fair amount of additional work to get more droop.  Bump travel more limited by spring height (solid height vs travel) and tire to body clearance.  A body lift would help both of those factors.

 

Hotbits I think sells 10" front / 12" rear travel struts for about $2000 with springs.  I have heard they bend when pushed hard, so we've never tried them.  I know a guy with a used set he'd probably sell, PM me if you're interested.

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Dont be sorry your the man you have a kick a$$ set up that most people would be jealous of for sure and who would know better than you guys who have done it and redone it till you got it im just guessin but in general long arms = long traval and short arms = short traval if you want more traval get longer arms the inverted strut are definitly the way to go but not cheap some custom cups and purches and its on but on to what 2 extra inches not worth it unless your gona race it weld up the rear end and call it a day forget about articulation your roo will never be a rock crawler with out a but load of work and money

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Dont be sorry your the man you have a kick a$$ set up that most people would be jealous of for sure and who would know better than you guys who have done it and redone it till you got it im just guessin but in general long arms = long traval and short arms = short traval if you want more traval get longer arms the inverted strut are definitly the way to go but not cheap some custom cups and purches and its on but on to what 2 extra inches not worth it unless your gona race it weld up the rear end and call it a day forget about articulation your roo will never be a rock crawler with out a but load of work and money

 

Thanks, just meant I don't know much about the EA cars.  You're probably right, a lot of work to get an extra couple inches of travel is probably not worth it for trail riding.  Being able to tune real offroad shocks for higher speed use is good even without increased travel, but not worth it for crawling.  Seems like it might be possible to get 10-12" even with short arms with enough body lift.  If we did a 4-6" body lift on an EJ we could probably get 14"+ travel with the stock links/arms.  Following to hear how the axles work out.

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  • 3 weeks later...

I have Heri axles on my '97 Forester since 2+ years. The inner boots are very fragile and the inner cv's now have some play but still do the job. Its not super quality but the design helped a lot for the long travel coilovers  (10"front, 11"rear, no body lift).

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  • 1 month later...

Did you check to see if the axles were hitting the crossmeber mine did was it the inner joint that blew or the outer mine the inner failed in just a few hundread miles but it was hitting the crossmeber and blew up the inner cup i droped my crossmeber another 1/2" to fix the problem but i have other issues to fix befor i can see if the spacers worked or not.

Edited by ferp420
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