Coilover Build Question-

[99xj4x4]

Im getting all my parts together for my axle swap. I have the hp king pin 60 front, 14 bolt rear w disc, 38.5s TSLs on 16.5 H1 wheels. The rear I plan to stretch slightly with a longer main leaf, but leaving the gas tank stock. I plan to keep the XJ right around 8” of lift.
So my question is what coilovers should I go with in the front? I was thinking fox/king/sway away 2.5 14”. 14+8.25= 22.25” collapsed length. My question is with 38s how much up travel am I actually going to be able to use? I can get a pretty sweet deal on dual rate 16” 2.5 Kings, but that makes the collapsed length 24.25”. Am I going to hate loosing those 2” of up travel? The other option to offset the loss in up travel is make brackets on the back of the 60 and try to get the coilovers down 2” off the axle tubes, but running the stock style 4 link w/ T&T arms space may become an issue.
Also for anyone running coilovers on their XJ what springs are you running?

Ideas for anyone running coilovers and big tires???

 

[99xj4x4]

Well thanks for all the responces :gee: LOL
So im getting a good deal on the 16s, they will just need a 205 or 180 spring, so ill have maybe 700 into them total. Im driving down to socal to get them friday.

 

[Darky]

Sorry, I am of no assistance, but figured I'dpost so you didn't feel as though nobody was paying any attention.

 

[Monster XJ]

i would check up on pirate in the cherokee section they typicaly have more knowledge on the the hardcore tech http://pirate4x4.com/forum/forumdisplay.php?f=83

 

[redneck23ms]

just run them up thru the hood if you want to use all of the uptravel on the 16"

 

[2001XJ-32]

Im with the Red Neck, you dont have to go "through" the hood but you can easily get a few more inches modifying your upper mounting location.

 

[XJ_ranger]

I can only use 12" of travel in the front of my rig - 4" up and 8" down. If I modified the trackbar, I ought to be able to get ~2" more up...

16" coilovers are REALLY long...

I'd set it up with as much uptravel as you can get, and the rest down with whatever shocks you end up with...

the brand of shock doesnt really matter all that much - they all function the same, putting the time into tuning will really make the difference...
(between the big 3 that is - Fox, King, Sway-a-way)...

as for spring rates - might want to shoot a PM to Goatman - he had coilovers, and might be able to give you a starting point? he also lives in Bako.
I'd give you the numbers off mine, but I run airshocks...

some 'good' pics of front coilover / airshock mounts -
http://www.rockhardxj.com/viewtopic.php?f=2&t=2423&hilit=air+shocks

 

[Jimbo_1321]

look at 53guy's build on pirate.
he was using 14" coilovers and was at about 6 inches above stock, so if you use his same method and use the 16" you should get just about the 8 inches over stock you want.
HTH

 

[Goatman]

I wouldn't get the 16's, they'll be too long and you'll be fighting clearance and uptravel with them. You also can't use that much travel, and you don't need that much travel. For example, both my XJ and my XJ buggy, Dave Taylor's rig, and Paul S's rig all work very well, and all have 12" shocks in the front.

Call me if you want, 706-1600.

 

[Goatman]

The other issue about having an extra long shock is getting the spring rate right. It can be done, but it's more complicated. Normally, you use longer springs with longer shocks, which means you need a softer overall spring rate to compress the longer shock to the same ride height, as spring force at ride height needs to be the same. You can use a shorter spring, and run the top coil adjuster down, but then you need to make sure you don't hit coil bind when it's compressed all the way. Not too big a deal, but it makes the calculations different as you need to check overall coil bind. And you might not like the softer spring rate if you use the longer coils.

Also, since you're limiting your uptravel with that long a shock, you'll work to get the same uptravel that you'd have on a 12" shock, that will leave you with more downtravel which will hurt you on climbs. You won't be happy with the big axles and meats if it won't climb. This means you'll need to limit strap the front end to control push off, so will never use the xtra down travel. You'll work extra hard to fit a shock that you'll never use the longer travel.

 

[vetteboy]

What are you looking to gain by going with coilovers?

 

[99xj4x4]

Well right now I have 13" of travel and I use every bit of it, so I totally disagree that more than 12 is pointless.
Im also sure I can stuff 16s under the hood, because Ive seen it done a few times.
I was planning on 14s but there are more deals on used 16s because they are more common on the trophy trucks.
Im planning on higher vavling and slightly softer springs.

Im looking at coilovers, for ride quality, getting the height lift I need, ez install, and they will end up costing almost exactly as much as setting up my 60 for stock XJ lift coils.


And Rich I may give you a call after work today.

 

[RCman]

Are you planning on recentering the H1s? What kinda uptravel do you have now and what are you looking for?
I know with my stock H1s, 39" Pitbulls, and HP D60 there is no way I could use all the uptravel a 16" shock would get me if setup correctly. The tires would just plan screw up the inner fender and the D60 would uppercut the oil pan.
I could cut it up similar to Goatman's in order to use them and I still don't think it would work very well, nor have all the travel. Or I'd need some ridiculous amount of lift just makiing it unstable.
I just finished my front 3-link and while I havn't had it off the jackstands, nor have I finished trimming. I am set with the 12" travel, just under 5" of uptravel and 7" of down should work very well up front. Shocks that is, I'm still using separate shocks/coils in the front for now; coilovers are just going in the rear.

Don't take what I typed above to harshly, just trying to make sure you don't jump into anything to quick and end up buying 16" coilovers you can't use. Goatman, XJ_ranger, Vetteboy and a few others really know what they are talking about. I learned more than a lot in the early stages just reading their posts.

...and they will end up costing almost exactly as much as setting up my 60 for stock XJ lift coils.

No way I am believing this, unless you are getting the coilovers for next to nothing.

 

[JeepFreak21]

Well right now I have 13" of travel and I use every bit of it, so I totally disagree that more than 12 is pointless.
Im also sure I can stuff 16s under the hood, because Ive seen it done a few times.
I was planning on 14s but there are more deals on used 16s because they are more common on the trophy trucks.
Im planning on higher vavling and slightly softer springs.

Im looking at coilovers, for ride quality, getting the height lift I need, ez install, and they will end up costing almost exactly as much as setting up my 60 for stock XJ lift coils.


And Rich I may give you a call after work today.

Easy install?

Billy

 

[99xj4x4]

No way RC Id never ask for advice and have someone give me their opinion/ experiences then get up set over. This discussion is exactly what I was hoping for.

So being able to use all the travel on the 16s isn’t that much of an issue, only reasons for the 16s over the 14s is because I can save $600 which means I can have and ARB from my front end within a month. Ive definitely ruled out 12”s because I like my rig flexy. If I need to suck up the axle on an obstacle Ill through the winch on it.

I would probably run a similar set up to the last build we did on a 93 k5.

The spring at the top sits completely compressed. I really like the way it floats going fast and how well it flexes in the rocks. It minimized the lift height and gives a great ride. I could just run a shorter and softer top coil and run a slightly stiffer spring under it and have them valved correctly for this and keep the lift height down and keep them functioning the way I want.

I want to recenter the H1s but right now it hasn’t been done, and since it will still be hwy driven I don’t want to do it my self, and fab shops here suck, so if I have it done Ill probably end up driving 2 LA to have it done, or just sell mine locally for a profit and buy some from the guy off pirate already re-centered (which is what I should have bought in the first place). Wheel spacers and offset steering arms to try and keep it close to the width it is now is the plan for now.
Ive thought about getting out the sheet metal brake and fabbing some new inner fenders, but really Id only gain an inch or two. Im just not sure its worth that much work yet, but its a possibility.
Clearance with the 60 and the oil pan is definitely one of my biggest concerns with this build. But I have definitely ruled out an over the axle truss because of this. And Ill definitely be running some good hydraulic bump stops.



Its a lot simpler to bend up 2 shock hoops and weld them to the already plated anybody and weld 4 tabs on to the 60 than it would be to fab/buy coil buckets, make solid shock mount, buy new 8" coils (bc my RE 7.5s are way too soft), buy external reservoir shocks, and move the upper coil bucket/mount (whatcha-ma-call-it) forward to correct spring angle.

 

[Goatman]

Well right now I have 13" of travel and I use every bit of it, so I totally disagree that more than 12 is pointless.
Im also sure I can stuff 16s under the hood, because Ive seen it done a few times.
I was planning on 14s but there are more deals on used 16s because they are more common on the trophy trucks.
Im planning on higher vavling and slightly softer springs.

Im looking at coilovers, for ride quality, getting the height lift I need, ez install, and they will end up costing almost exactly as much as setting up my 60 for stock XJ lift coils.


And Rich I may give you a call after work today.

Call me. Just because you use more travel doesn't mean it's giving you better performance. I've seen many examples of longer travel trail rigs getting spanked by shorter travel trail rigs. Big tires and heavy axles provide so much traction that flexing through obstacles is nothing, every rig can do it. What seperates a rigs capability is how it handles the really technical climbs and obstacles where stability is king and flex is barely an issue. You might be able to get the 16's to work and be happy, so who can say, but you don't need them to get the best performance, and 12's or 14's will be easier to mount and tune.

Just an FYI, I just bought new shocks for the front of the buggy, high end ORI air shocks, and they're 12". Dave Taylor just bought (partial sponsorship deal) King triple by-pass air shocks for his buggy, and he also kept the 12's in the front. We both could have gone to 14", but we just don't need more travel.

Just talking here........you have to get what you think will work best for your situation.

 

[99xj4x4]

I got tied up with school stuff today, I should be free tomorrow.
Oh and I met your new neighbor Flem with the blue YJ, he was at HRE, seems like a cool guy.