Don't swap the Med for Heavy OEM Springs

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my 863s got me 4" of lift with truck empty.
A bunch of recovery stuff in the back, I'd say at least 200 lbs, more like 300 lbs gave a 1/2" drop. A trailer in the back did about the same.

Ride is just fine and it's great to have the extra clearance and not drag the butt any more. Need to adjust LSPV but trivial and there is a bit of rake when unloaded but I don't care. Sure glad I went with 63s and not meds...
 
alkaline747trio said:
Here is what I am gathering from this..

Mediums: 2.5" lift no load
Heavies: 3.5" lift no load, 2.5" lift loaded 200#
J's: 4.5" lift no load, 3.5" lift loaded 200#, 2.5" lift loaded 400#


Sound about right?
Click to expand...




No.
 
So I wonder what springs I should get? Can anyone help?

I was thinking Heavy/heavy.

Up front:
ARB bumber
Warn M8000

Back:
big roof rack
rear ladder
tire carrier and 258/75/16 BFG AT
plus I carry about 100-150lbs of gear.

Getting:
Sliders (as soon as I make em)
Rear drawer system (as soon as I make it)

I was thinking heavy/heavy but mayne I should get heavy/J's?

Thanks,
Nick
 
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I run heavy fronts and medium rears (with BroncoII-IIRC bags for towing/loading times - deflated for daily use)

Front has an ARB and a 10k T-Max winch. Std OME lift length shocks all around, caster bushings (installed with Slee's kewl little press dealio).

Prior to the winch/bumper and while running med/med's, it rode a little rough...with the added weight and the heavy/med setup, I'm quite pleased with the daily ride. There is minimal rake as well, sits close to level.

sliders are coming, but that weight is centered and won't effect rake...
 
alkaline747trio said:
Then correct me...
Click to expand...


Search my friend, search.....;)

An un-loaded 864 lifts about the same ammount as an unloaded 863J (both of which are about an inch or so heigher than an 863). It takes twice the weight to lower 864's to any given height as it takes to lower 863J or 863.

I would not run 864's unless you pack a lot of extra weight all the time.

Read this thread:


https://forum.ih8mud.com/showthread.php?t=69927
 
We're talking 850 vs. 851 here.
We also seem to be operating under the (logical) assumption that 860 and 863 have the same rate (just like the front), but this has not been explicitly stated.
Anyone?

I think davis drafting (post #36) hit on the only difference between 850 and 851 with spacers. You'll have slightly less travel with the 851+spacer setup compared to the longer 850. But I bet the difference is negligible.

I guess it would depend on the number of coils in the spring. (More coils would "bottom out" sooner)

Springs are interesting things.
My physics go thru college, but I doubt I have a better understanding than everyone else here.

My understanding of springs, as I think through this question:

Per length of coiled spring,

More coils = less deflection per unit of compression = less force to compress = softer spring.

Fewer coils = more deflection per unit of compression = more force to compress = harder spring.

To make the 850 taller than the 851 OME would have to either add more coils, "stretch" the spring, or a combination of both. I would guess that a combination of both would be needed to keep the same spring rate. This would probably also net no change in travel between maximum compression and unsprung length?

Of course, this ignores the effect of different materials in the springs.

Just thinking out loud here.

Hayes

P.S. I haven't had the opportunity to compare the ride of 850/863 vs 851/860, but with a light rear end, the bumps are a bit harsh under the rear axle.

Hayes
 
From Beo...........
Beowulf said:

==============================================

OME Springs:

General rules:
unladen 864=5" lift or 2" w/400 kg load (20mm wire)
....... 863=4" lift or 2" w/250 kg load (19mm wire)
....... 860=2" lift or 1.75" w/a gas tank (18mm wire)
....... 850=2" lift w/some weight(dual batteries etc)
....... 851=2" lift w/bar & winch, dual batteries, etc
....... Stock springs 16mm wire.

================================================

Spring......bar...free.......nbr.....coil......spring
number......dia...height....coils....weight....rate (lbf/in)
..................DS..PS

Front
850.........17mm..495/505mm..9.8.....7.3kg......220 lbf/in
850J........17....515/525....9.8.....7.3........220
851.........17....475/485....9.8.....8.1........220
861.........16....480/490...10.4.....7.0........220

Rear
860.........18....480/490....8.3.....8.1........220
862.........17....460/470....9.0.....8.0........240
863.........19....480/490....8.3.....9.2........250
863J........19....505/515....8.3.....9.2........265
864.........20....480/490....8.3....10.3........320

Spring...bar...free ht...# of...coil....spr rate
number...dia....DS/PS....coils..weight..(lbf/in)
------+++----++-------+++-----++------++--------
850......17mm..495/505mm..9.8....7.3kg....220
850j.....17....515/525....9.8....7.3......220
851......17....475/485....9.8....7.3......220
861......16....480/490...10.4....7.0......220
860......18....480/490....8.3....8.1......220
862......17....460/470....9.0....8.0......240
863......19....480/490....8.3....9.2......250
863j.....19....505/515....8.3....9.2......265
864......20....480/490....8.3...10.4......320

===============================================

OME shocks

............. Open ......... Closed
............ length ........ length
N70 ......... 614 .......... 354
N71E ........ 620 .......... 370
N74E ........ 620 .......... 370
N73 ......... 614 .......... 354
N73L ........ 667 .......... 387
N74L ........ 667 .......... 387

================================================



I see there are a couple of minor discrepancies. As I recall, I got these from 2 different sources.

-B-
Click to expand...
 
There's the info right there.
860 and 863 have different spring rates.
That would verify the harsh feeling with a light rear end.

I guess the higher spring rate of the 863's are responsible for the increased ride height rather than the longer spring in the 850 - 851 comparison.

Hayes
 
850's would have the advantage of no spacers to fail or flatten.
851's + spacers has the advantage of lower cost if you already own the springs and don't mind risking a spacer failure and it's fairly low cost replacement.

If you don't own either set yet, I believe several people have run the 850f/860r combo successfuly with a stock bumpered rig and been level without any spacers. I'm sure every rig differs a bit, so there may be no perfect answer.

CDan - Thanks for re-posting the spring info that Beo had put together. Does anyone know the spec's on Slee's 4" lift and how it fits into all of that info? I would love to know the spring rates that are used on his 4" kit, but haven't asked to see if it's "confidential" or not.
 
xxxr your questions are really for another thread. stock caster varies on 80s as does the impact of bumpers and spacers between trucks. The short answer is that once you do it you will need to have your resulting caster measured then proceed accordingly. if you are very paranoid have your stock caster measured and we can then make an educated guess of the impact but it would be such a guess that I would not waste my money.
 
semlin said:
xxxr your questions are really for another thread. stock caster varies on 80s as does the impact of bumpers and spacers between trucks. The short answer is that once you do it you will need to have your resulting caster measured then proceed accordingly. if you are very paranoid have your stock caster measured and we can then make an educated guess of the impact but it would be such a guess that I would not waste my money.
Click to expand...

I'm running the 2.5 lift with the caster correction bushings... I just wondered if the spacers would raise the front enough for it to be an issue, or if the Bar would sink it enough to return to it's proper height. I ordered a set, as I plan on a bar next year.

You're right though, this is a specific that relates to caster and not just spring height. :doh:
 
So... ya'll think I need the spacers with an ARB Bull, winch ready, but no winch uninstalled?

I purchased a set of 1.25 (I think, I know they are just over an inch from Man O Fre) spacers for when I add the Bull. I was looking forward to leveling the rig out anyway, but I don't want to run with the rear squat either. Anyone run this?

THANKS!
 
A good reference page since ARB's site is less than stellar...

OME spring rates

I won't get into what everyone should run on their truck. My preferred set up is J's up front and 863s in the rear. Sat level and rode great. Don't ask why I don't run it anymore. i'm dumb.
dmc
 
two diffrent springs of the same rate one being longer,the longer spring will still have a stiffer rate because there will be more coils for compresion,coil spring gain rate as the coils are compresed.so more coils to compress more actual spring rate.
 
dmc said:
I won't get into what everyone should run on their truck. My preferred set up is J's up front and 863s in the rear. Sat level and rode great. Don't ask why I don't run it anymore. i'm dumb.
dmc
Click to expand...

What shocks did you use -- Ls up front and ordinaries in the back?
 
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ed97fzj80 said:
What shocks did you use -- Ls up front and ordinaries in the back?
Click to expand...

I ran regular OME shocks front and rear. I now have J's all around with spacers up front and L shocks. If my truck isn't loaded all the time it rides like a rock. I sold that set up to someone else thinking I wanted to run 315s. now i'm not so sure i made the right choice.
dmc
 
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dmc said:
I ran regular OME shocks front and rear. I now have J's all around with spacers up front and L shocks. If my truck is loaded all the time it rides like a rock. I sold that set up to someone else thinking I wanted to run 315s. now i'm not so sure i made the right choice.
dmc
Click to expand...

dmc -
Thanks for mentioning that. I have medium all around right now with MR G up front. I have the J's springs sitting in my garage but thinking I would end up just using them on the front and either keep the 860 rears or go for some 863s. I've been thinking about keeping the regular OME shocks in. I guess the only drawback would be not gaining any droop.
 
850J/864 and standard shocks here. I have not felt the need for L shocks with this setup. Bear in mind that the extra drop costs you compression and the net total travel remains about the same.
 
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