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Discussion Starter #1 (Edited)
Version 2.0 is on page 6 with some other cool stuff too http://www.fjcruiserforums.com/forums/suspension-steering-tech/154893-superflexy-cheap-more-expensive-if-youre-into-bigthumb-6.html

"Bilstien 5100 #24-186711 front shocks on first/second setting for the old "FJ lean" with stock springs[for easy compression to the bump-stops] and a 0.5" top plate spacer for the extra extension[see explanation in thread].
Lightracing upper control arms to clear the spring at full droop[see alignment tips in thread, but basically zero everything after shifting the wheel forward for 35s]
Metaltech 19.25" medium rear springs
Pro-Comp 29.77" long shocks with 12.68" of travel at the shock out back. ES9000 #929510 mounted as seen on page one with pro-comp 600020 lower bushing, these do contact the lower link and axle housing under full articulation.
1.5" rectangle tube bump stop spacers out back, this and the Spidertrax spacers keep the top of the tires off the top of the wheel well at full tire stuff.
Extended rear brake lines,
Extended: wheel speed sensor lines, diff lock actuator lines via existing slack in lines and brackets, pulled existing slack down on the front lines
Removed: both anti-sway bars, both e-brake line frame side brackets.

A set of 1.25" Spidertrax spacers set the track width out further to help a little too.[offset and alignment are the key to 35s]

all in all, about $1250 + tires[315/70r17 Hankook MT]"


thought the first page needed a better picture to look at and quicker access to the parts list, great to see people taking numbers!

stock springs and little to no lift up front, bump-stop contact on the front A-arms is key.



Old initial post starts again>>>

so i noticed most of the kits out there are sold with rear shocks that are 2 inches shorter than need be and i've never been one for kits anyway. I should say some of them are pretty damn good, like if you want to run 35s then just go get the metal tech long travel rear kit that ****s perfect for 35s. if you're running a smaller tire then adding three inches to the rear bump stops is a pretty heavy price to pay for a 28.5" shock.

speaking of travel only, The front doesn't really matter much beyond matching the spring rate or preload to the weight of the vehicle. I'm running Bilstein 5100s on the 4th setting with the stock spring and no swaybar. $200.

The Rear is a Toytec super flex spring(many of you have this already) with a Procomp ES9000 #926514 , 26.79 inches long with 11.23 inches of travel. no rear sway bar. extended rear brake lines. no need for a limit strap. $180 spring + $100 shocks +$70 brake lines

for better quality the OME LTR shock at 26.23 inches and 11 inches of travel, can be used with very similar results. These have remote reservoirs and run about $250 apiece, IIRC they are designated for the 80 series land cruiser as are the pro-comps i'm using.

about $550 and no sway bars is enough to cover a 2.5" lift and lots of flex.






The rear fully extends with all stock arms and compresses to the bump stop, the front is just onto the bump stop here also, i'll have to see about getting it there sooner later this year.

good luck and go hang a tire below the body of you FJ :bigthumb:

and i just wanted to post these again, two of the best posts on this forum...

http://www.fjcruiserforums.com/forums/suspension-steering-tech/56511-flexing-ome-extra-heavies-ltr-rear-shocks.html

http://www.fjcruiserforums.com/forums/how-technical-articles/57523-ome-suspension-kits-option-guide.html
 

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Discussion Starter #3 (Edited)
you mean the free length? 16.875 inches
 

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Discussion Starter #6 (Edited)
About one more coil than stock springs, 5/8th inch per coil at 8 coils is 5" at coil bind, but you'll get to the bump bump stops before that. whats interesting is I could potentially use a longer shock with a rear coil spacer, but i'd have to look into axle and trailing arm contact and other more difficult questions.
 

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Discussion Starter #7 (Edited)
The other side of that is to measure the space between the bump stops and the space between the shock mounts and verify that there is less space between the bump stops than the difference between the partially compressed shock and compressed length of the shock. Then you have numbers for full compression and a rough number for checking articulation clearance, you need to check the same measurements at maximum angle of articulation. That's the part I assumed was ok and checked on the RTI ramp. I'll have to look at the numbers again to see how much further I can go.

^that's taking measurements four wheels down on level ground.
 

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Discussion Starter #8 (Edited)
mounting the Pro Comps:

Top stem mount:
new bushing come with the pro-comps i only used the top ones, i used the stock bottom mounts as pictured below.





The bottom eyelet mount: use two washers per side
There is a 3/4" bushing provided with the shocks, you'll need to grease it inordet to mount it in place of the smaller bushing that's per-installed. I also picked up a two large washers ID 3/4", OD ~2.5", width ~3/8", i ground the OD down to about 1.25" and used it as a spacer installed first, in order to spacer the shock out from the mount bracket on the axle housing. The Pro-Comps are a little portly and the lower mount is a little small, the small spacer took care of both issues very nicely.

^looking at the picture now, two spacers would probably be better than one, that bolt is tight.
 

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About one more coil than stock springs, 5/8th inch per coil at 8 coils is 5" at coil bind, but you'll get to the bump bump stops before that. whats interesting is I could potentially use a longer shock with a rear coil spacer, but i'd have to look into axle and trailing arm contact and other more difficult questions.
Interesting I would have thought the compressed height of the spring would have been more. 12" travel out of the spring is nearly identical to the metal tech spring.

Keep in mind your bump stops will fully compress all the way at a significant load. That's why they don't tell you much, just that they should stop the axle before coil bind. Just the point that they engage. Also need to make sure your tires don't make friends with the fender well before bump anyways.

The other side of that is to measure the space between the bump stops and the space between the shock mounts and verify that there is less space between the bump stops than the difference between the partially compressed shock and compressed length of the shock. Then you have numbers for full compression and a rough number for checking articulation clearance, you need to check the same measurements at maximum angle of articulation. That's the part I assumed was ok and checked on the RTI ramp. I'll have to look at the numbers again to see how much further I can go.

^that's taking measurements four wheels down on level ground.
You'll need to work back through the triangles though cause the axle 1" from the bump stop does not equate to 1" left of your shock due to the motion ratio. Just thought I'd clarify that for anyone reading.

Spot on though and really good insight for some decent articulation. Great writeup :cheers::bigthumb:
 

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Discussion Starter #10 (Edited)
Interesting I would have thought the compressed height of the spring would have been more. 12" travel out of the spring is nearly identical to the metal tech spring.
the Metaltech spring is suppose to be 19" and it has 10.5 ~ 11 coils, its the proximity of the top coils that reduce it compression so much. Shocks are of parallel unequal design when comparing extension and compression alone. It would take quite a bit of force to get it to 5 inches, IIRC its like 285lbs/inch.


Keep in mind your bump stops will fully compress all the way at a significant load. That's why they don't tell you much, just that they should stop the axle before coil bind. Just the point that they engage. Also need to make sure your tires don't make friends with the fender well before bump anyways.
I disagree about the ability of those bump stops to compress, i can't imagine them compressing 50%. < and most of that from the slit cut in the bottom of them, those things are little rocks and i feel it every time i come down on them.

The coils location inside of the shocks makes sure that the maximum compression of the spring can only occur while the axle is compressed evenly from both sides. Under articulation and on the bump stop the springs compression is a trigonometric factor of it perpendicular compression, ensuring articulation compression of a shock always results in less spring compression than equal compression of both shocks to the same level.

You'll need to work back through the triangles though cause the axle 1" from the bump stop does not equate to 1" left of your shock due to the motion ratio. Just thought I'd clarify that for anyone reading.
I want to work back through the angles as i was expecting to have to run about a 1" bump stop extension, so i want to figure out where i was wrong there. The angle of the axle to truck in the RTI ramp picture isn't very much, maybe 30ish degrees so the extra compression on the shock will be pretty small since it mounts so close to the location of contact with the bump stop.

I need to get it onto an RTI ramp that is more stable, my help was afraid for his life LOL, but seriously that **** moved and its leaning in the picture...

Definitely appreciate the conversation, I'm not one for writing this stuff down its more fun talking through it all :cheers:
 

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the Metaltech spring is suppose to be 19" and it has 10.5 ~ 11 coils, its the proximity of the top coils that reduce it compression so much. Shocks are of parallel unequal design when comparing extension and compression alone. It would take quite a bit of force to get it to 5 inches, IIRC its like 285lbs/inch.
They are either 19" or 21" I can't remember. I posted the free height and compressed on here somewhere. Too long ago though and don't remember where.

All depends on what type of offroading you do. Not that hard at all to fully compress the suspension if you are going at speed, slow not as easy.


I disagree about the ability of those bump stops to compress, i can't imagine them compressing 50%. < and most of that from the slit cut in the bottom of them, those things are little rocks and i feel it every time i come down on them.

The coils location inside of the shocks makes sure that the maximum compression of the spring can only occur while the axle is compressed evenly from both sides. Under articulation and on the bump stop the springs compression is a trigonometric factor of it perpendicular compression, ensuring articulation compression of a shock always results in less spring compression than equal compression of both shocks to the same level.
Agree to disagree on that one. If you are only going slow then sure its not easy to compress the bumps (sounds like what your thinking based on your rock comment). Going at speed its quite easy to compress the rubber bumps stops.

Yes, I haven't been refering to articulation in my posts above. Only verticle axle travel as I was interested in the shock sizing question. On articulation you've essentially got a lever and your comments are accurate


I want to work back through the angles as i was expecting to have to run about a 1" bump stop extension, so i want to figure out where i was wrong there. The angle of the axle to truck in the RTI ramp picture isn't very much, maybe 30ish degrees so the extra compression on the shock will be pretty small since it mounts so close to the location of contact with the bump stop.

I need to get it onto an RTI ramp that is more stable, my help was afraid for his life LOL, but seriously that **** moved and its leaning in the picture...

Definitely appreciate the conversation, I'm not one for writing this stuff down its more fun talking through it all :cheers:
I did the math for the OEM motion ratio somewhere on here, but I'm not sure if I left the post up. Can look when I get home later this week and send it to you to confirm your numbers against.

Why not pull the springs out and cycle the suspension without them to see where bump needs to be for the shocks. Can pull your bump stops out so they aren't limiting anything. Cycle the axle vertically and that will set most of your max bump points. Can articulate it as well and confirm your bump points are sufficient and your tire isn't hitting the inside of the wheel well on an angle or anything. :cheers:
 

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Discussion Starter #12
Agree to disagree on that one. If you are only going slow then sure its not easy to compress the bumps (sounds like what your thinking based on your rock comment). Going at speed its quite easy to compress the rubber bumps stops.
I would have to say that to compress the bump stop completely would require displacing it completely and thus cutting it in half. The material will compress logarithmically to a limit before failure, so most of it is there for the sake of it's own structural integrity, but there are only two ways forward from here, to either put a camera in front of one and go blasting or get lots of material properties, charts and really boring equations that I'm not familiar with. hahaha i wish i had the time to run the camera

I did the math for the OEM motion ratio somewhere on here, but I'm not sure if I left the post up. Can look when I get home later this week and send it to you to confirm your numbers against.
I'd be happy to see what you worked up :cheers:

Why not pull the springs out and cycle the suspension without them to see where bump needs to be for the shocks. Can pull your bump stops out so they aren't limiting anything. Cycle the axle vertically and that will set most of your max bump points. Can articulate it as well and confirm your bump points are sufficient and your tire isn't hitting the inside of the wheel well on an angle or anything. :cheers:
Eventually yes, I also want to look at how much longer of a shock can be installed before the lower links start to contact the axle and when the e-brake cables are stretched too far. I would really like to get a 31" Bilstein 5165 in placed with an upper eyelet mount welded in place 2.4" higher and leaning into the wheel well, I'm sure bound bushings would be a real issue then if they aren't already and that would probably require a custom spring, etc, etc...

I went out and did a couple follow up measurements and the shock will allow for the bump stop to compress about an inch out of its two inches of thickness before they bottom out by the numbers. :bigthumb:
 

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the Metaltech spring is suppose to be 19" and it has 10.5 ~ 11 coils, its the proximity of the top coils that reduce it compression so much. Shocks are of parallel unequal design when comparing extension and compression alone. It would take quite a bit of force to get it to 5 inches, IIRC its like 285lbs/inch.
Just wanted to clear up that it is the Metal Tech LT shocks, not the springs, that require the bump stop extension. The shock body is longer than normal, and without the bump stop extension you'd bottom out the shocks well before hitting the factory bump stops.

Coil free height is 19.25", the shock has 11.5" of travel.

LT coil vs. ICON 2" lift coil


LT shock vs. ICON 2" lift shock


Full bump on the driver's side (passenger is not fully extended). The spring has plenty of compression left, it is the shock body length that requires the bump stop extension.
 

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Considering the length and amount of travel from that Pro Comp shock, are you sure you're not bottoming out the shock before hitting the bump stop? I know on mine once I hit the bump stop I have maybe 0.5" of travel left in the shock.
 

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Discussion Starter #15
the Metaltech spring is suppose to be 19" and it has 10.5 ~ 11 coils, its the proximity of the top coils that reduce it compression so much. Shocks are of parallel unequal design when comparing extension and compression alone. It would take quite a bit of force to get it to 5 inches, IIRC its like 285lbs/inch.
Just wanted to clear up that it is the Metal Tech LT shocks, not the springs, that require the bump stop extension. The shock body is longer than normal, and without the bump stop extension you'd bottom out the shocks well before hitting the factory bump stops.

Full bump on the driver's side (passenger is not fully extended). The spring has plenty of compression left, it is the shock body length that requires the bump stop extension.
Sorry but, what your quoting isn't implying what it looks like you're thinking it's implying.

I was mostly talking about inefficiency in shock design and inefficiency of spring design, with some reference back to spring binding height. Earlier, I was saying that the spring would bind with OEM bump stops. Your picture here helps, it shows 11.25 coils, assuming 5/8 inch per coil as well that's 7 inches of height at coil bind, and there isn't that much space once you start getting into the OEM bump stop.

Some where along the way i did loose the measurements of their Vs 2.0 shock, and everything I have is off by 1/2" or so. Do you know if 28.5" is the correct length between mounting points?

I do like Metaltech's kit very much when used with 35" tires, Its a very efficient collection of components that give a lot of travel, very easily, I dare say more than any other. I don't care for it with 33" or less tires, as now every time the suspension is full compressed to the bump stop, your tire has to start lifting the back of the truck 3" soon than it would have with OEM bump stops and without the benefits of a 35" tire. A good question is, even with a 35" tire, do the costs out weigh the benefits on that particular rock? all of that could be a whole other thread and subsequent argument with lots of fun angles:cheers:
 

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I would have to say that to compress the bump stop completely would require displacing it completely and thus cutting it in half. The material will compress logarithmically to a limit before failure, so most of it is there for the sake of it's own structural integrity, but there are only two ways forward from here, to either put a camera in front of one and go blasting or get lots of material properties, charts and really boring equations that I'm not familiar with. hahaha i wish i had the time to run the camera

Honestly I think the bumps dispalce a lot more than you are thinking. You'd be surprised at how much that durometer rubber can move. I've seen aftermarket ones which are stiffer than OEM compress all the way to the frame. We used to do the load cell vs displacement testing on various durometer bump stops for a passive x/y system on a suspension seat trying to target a specific profile. This varied from linear dampening stops to variable dampening designs. You'd seriously be surprised how much the stuff compresses and still maintain its structural integrity. Anyways, just my opinion that they displace a great deal.

Anyways, getting offtopic, as I said nice writeup.
 

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Discussion Starter #20 (Edited)
lots of pictures lots of measurements and good results. I also edited that crap out of post #8 for mounting the pro-comp shocks.

rear springs:
stock 15.125"
OME 16.25"
toytec 16.875" (pictured below)
metaltech 19.25"


dust boots = mud holder grinding mill, maybe just don't ziptie the bottom?
also, check out the parking brake cable bracket, if you bend it so that it points parallel to your lower suspension link and pull it out about an inch so its no longer above the lower suspension link it will slid freely with any shock at least up to 29 inches long. as is ir binds with the stock rear shocks before full articulation.


the toytec 16.875" spring unseats here:


1/4" away from full compression on the shock and i'm holding the truck up on the axle and the bumpstop, no spring. Motion ratio is working well for the shock.(i'm measuring from the back side of the bushing mount where the shock body would impact the upper mount)


interesting side note, Toyota doesn't know how to place a bumpstop...


interesting side note at full articulation bump


 
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