Spring upgrade for weight, not lift question

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Fourbtgait

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Hello everyone, first post, first 4runner. Always had trucks, still have a CJ.
2014 SR5 Premium. Going minimal upgrades, already traded tires, stock size, better grade, installed Bilsteins, front at .85, installed a gear box in rear, sliders. Looking at a Bud Built hidden winch set up this winter.

I have been spending a lot of time researching posts on air bags, coil spring brands, sizes, etc. i do not want a huge lift. Looking more for the added in weight capacity, probably about 500 pounds from winch, sliders, constant gear, etc. OME lift is 2", Ive read FJ springs typically 1". But will trading in FJ springs offset the added gear weight or should I suck it up and buy the OME springs to gain back the weight capacity?

Would 1" Fj lift settle down then to stock height?
Would 2" OME settle down to just 1" above stock height?
Would 2" look stupid with SR5 stock tire size?

Thanks.
 
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It's pretty easy to figure out. It's the added weight/spring rate = drop. For instance the front stock springs are at about 500 lb/in each. So every 100 lbs add to the front only drops you about 1/10 of an inch. The rears are much softer. I think they are about 200 lb/in but am not sure. So weight in the rear has a much larger effect on stock springs. Finding your spring rate will let you find your settled weight pretty easily unless they are very progressive rate springs.
 
Swarty said:
It's pretty easy to figure out. It's the added weight/spring rate = drop. For instance the front stock springs are at about 500 lb/in each. So every 100 lbs add to the front only drops you about 1/10 of an inch. The rears are much softer. I think they are about 200 lb/in but am not sure. So weight in the rear has a much larger effect on stock springs. Finding your spring rate will let you find your settled weight pretty easily unless they are very progressive rate springs.
Click to expand...
The calculation on the front is not that simple, as it is not a spring between the frame and a solid axle, it is mounted to a lever (LCA), hence the far higher lb/in spring rate.
 
Swarty said:
It's pretty easy to figure out. It's the added weight/spring rate = drop. For instance the front stock springs are at about 500 lb/in each. So every 100 lbs add to the front only drops you about 1/10 of an inch. The rears are much softer. I think they are about 200 lb/in but am not sure. So weight in the rear has a much larger effect on stock springs. Finding your spring rate will let you find your settled weight pretty easily unless they are very progressive rate springs.
Click to expand...

I think this theory holds true for the rear springs since they sit on the axle. For the fronts, the lower control arm acts as a lever and when the spring moves an inch, the distance traveled at the hub (near wheel) is more than an inch.



Here's a diagram which helps explain:

Suspension Worksheet | eibach.com/america
 
Sigh, leaf springs are so much easier, at least for old farts like myself...
Thank you for the replies, insight.
So I need to find someplace the weight/spring rate for the FJ springs to make the comparison to OME, which I have already located.
Basically, though Swarty's simplification may not hold true for the fronts, the drop from steady weight is not that great.
Does anyone make a higher weight/spring rate that does not entail a lift also?
As a side note, I will add air bags to the rear for full gear or trailer use.
 
So maybe this chart in another post answers my question if I understand it and the posts above. Though I am assuming the numbers are for a 2014 also.

http://www.toyota-4runner.org/4th-gen-t4rs/162125-coil-rates-oem-4runner-oem-fj-moog-others.html

The spring rates for a 4r and FJ are basically the same, just overall coil height is different.
So if I want to gain back the added weight, I do need to go OME in the higher weight/spring rate.
Accept the lift from longer coil length. Possibly won't need the .85 from the Bilsteins then.
Seems to simple, but the higher capacity gets rid of the last bit of nose dive, keeps it more level in turns. Also probably wont need the air bags?
 
Following with interest!
I have similar requirement of higher load carrying ability without significant lift. (contemplating new front bumper/sliders, plus occasional heavy trailering)

Must confess, my old brain gets addled with all this talk of weight vs drop, spring rate etc. I would rather not deal with all that stuff - that is why we have 1engineer, no?!

I just want someone to tell me: "You just add the OME kit, and you'll be alright, my son!"
 
I wish it was that easy Raven. But what Swarty, Jeremy and Atl4r wrote helped me to understand the spring charts and all the talk.
There is no simple answer as I dig deeper, especially for front coils.
Then I find out front OME can be used with Bilsteins but best with their shocks.
 
Here are some specs I found for the OME front springs. After reading up top I see the table posted, gotta bookmark that thanks for the link
Fourbtgait. I was always under the impression that the fronts with higher numbers had higher spring rates with the exception being the 886, guess I was wrong.

OME 2883 375mm, 590lbs/in, Bar Diameter: 16.5 mm,

OME 2884 390mm, 590lbs/in, Bar Diameter: 16.5 mm,
OME 2884 Coils designed for 0-50 lbs of additional front weight (no bumper and no winch)

OME 2885 395mm, 590lb/in, Bar Diameter 16.5mm
OME 2885 Coils designed for 70-180lbs of additional weight (with bumper or winch only)

OME 2887 400mm 590lb/in Bar Diameter 16.5mm
OME 2887 Coils designed for 250+ lbs of additional front weight (bumper & winch)
 
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Thankyou, fourbtgait and Taco 04 - useful information! I am sure the information was available to me somewhere else on the forum, but I had not come across it, and it certainly is easier when it shows up neat and tidy like that in a post.

On a side note, I have noticed in general that the members of this forum tend to be more patient, considerate and understanding than some of the other forums I am on. This was far more helpful than someone yelling at me to: "Use the search function, fool!"

I am now a little closer to a basic understanding of the difference between coil springs. (I will never know as much as the gearheads here, and that's OK, as long as I can rely on their knowledge to keep me out of trouble!).
 
Thankyou 1engineer, I will check out those links! Despite what I said previously, I really do like to understand the mechanical systems on my vehicles, and this will help me make the right decisions regarding a suspension upgrade.
 
You could always do an adjustable coilover setup like Radflo or Icon for the front and just do air springs helpers for the rear. This would allow you to dial in the exact height you want AND get the extra firm spring.
 
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