Coilover Rates

Rock Toy

Rock Toy

TJ Enthusiast
Joined
May 3, 2020
Messages
251
Location
San Francisco
Now that I am done with my mid-arm build, I have had a chance to drive the Jeep around a bit. I am running Fox 2.0 C/O's with remote reservoirs. My shock tuner started me out with 225/200 in the front and 200/150 in the rear. The front appears to be perfect but the rear is sagging/bottoming out when fully loaded. 2" of preload all around. 200 psi of Nitrogen in each shock. I am going to swap out to 200/200 in the rear and then head out to see him for valving. I trust his judgement but am curious to see what others are running. I have a 2005 TJ with a 99" wheelbase. Hanson bumper in the rear with a 37" spare mounted on a Forged AL Beadlock.
 
Rock Toy said:
Now that I am done with my mid-arm build, I have had a chance to drive the Jeep around a bit. I am running Fox 2.0 C/O's with remote reservoirs. My shock tuner started me out with 225/200 in the front and 200/150 in the rear. The front appears to be perfect but the rear is sagging/bottoming out when fully loaded. 2" of preload all around. 200 psi of Nitrogen in each shock. I am going to swap out to 200/200 in the rear and then head out to see him for valving. I trust his judgement but am curious to see what others are running. I have a 2005 TJ with a 99" wheelbase. Hanson bumper in the rear with a 37" spare mounted on a Forged AL Beadlock.
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Rear is sagging or the rear is bottoming out? They are not the same thing.
 
Unloaded, the Jeep sits level and performs great. With a passenger and a rider in the back seat, it settles an inch or two and then bottoms out on bumps. Unloaded, I have around 5" of shaft showing (before the rubber bump-stop).
 
Rock Toy said:
Unloaded, the Jeep sits level and performs great. With a passenger and a rider in the back seat, it settles an inch or two and then bottoms out on bumps. Unloaded, I have around 5" of shaft showing (before the rubber bump-stop).
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When calculating bumps get rid of that rubber stop. It compresses and can fall off.
 
Rock Toy said:
Unloaded, the Jeep sits level and performs great. With a passenger and a rider in the back seat, it settles an inch or two and then bottoms out on bumps. Unloaded, I have around 5" of shaft showing (before the rubber bump-stop).
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Pick your most common ride height and tune around that. Otherwise, it is going to suck the rest of the time.
 
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Are rear coil overs hard to get right now guys?
 
Rock Toy said:
My understanding is that all Coilovers are in short supply right now.
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Thank you. It is an odd time in many industries on availability- spray foam for houses has been a recent issue. Beats all I’ve seen.

Have you got a build thread on that. Sounds like a winner you have going.
 
Rock Toy said:
So.....the original question is what are other running on THEIR Jeeps? I got a bunch of advice and then the discussion transitioned to the availability of parts. Bringing it back in focus.
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I run the combined spring rate that gives me the design ride height. The design ride height is based on the corner weight with the amount of uptravel I build into the rig. I "weigh" each corner with a lower spring with a known rate and length. I bolt on the shocks at all four corners and set it on the tires with that single spring on and solid blocking to spring the dual rate slider from moving up so it can support the weight of the rig. Then I measure how much each corner has compressed the lower spring exactly. That is then used to get the corner weights. I give those to my tuner and he gives me back the upper and lower springs I need to use with the preload.
 
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mrblaine said:
I run the combined spring rate that gives me the design ride height. The design ride height is based on the corner weight with the amount of uptravel I build into the rig. I "weigh" each corner with a lower spring with a known rate and length. I bolt on the shocks at all four corners and set it on the tires with that single spring on and solid blocking to spring the dual rate slider from moving up so it can support the weight of the rig. Then I measure how much each corner has compressed the lower spring exactly. That is then used to get the corner weights. I give those to my tuner and he gives me back the upper and lower springs I need to use with the preload.
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Yep, I know all of this. I have ready all of your posts and am completely aware of how it works. And we did that with mine as well before sending the figures out to the tuner. And his exact words were "maybe it will be right and maybe it won't....setting up a truck with custom suspension is trial and error". Maybe you nail it the first time very time but my understanding is that most folks don't. And I am just curious as to what other folks run, regardless of whether or not its going to work for me. A loaded down street driven TJ on 37's is really not THAT unique and I am guessing that most folks are running a combination of a 200 lb spring and a 150-250 lb spring in the back of their TJ's.
 
Rock Toy said:
Yep, I know all of this. I have ready all of your posts and am completely aware of how it works. And we did that with mine as well before sending the figures out to the tuner. And his exact words were "maybe it will be right and maybe it won't....setting up a truck with custom suspension is trial and error". Maybe you nail it the first time very time but my understanding is that most folks don't. And I am just curious as to what other folks run, regardless of whether or not its going to work for me. A loaded down street driven TJ on 37's is really not THAT unique and I am guessing that most folks are running a combination of a 200 lb spring and a 150-250 lb spring in the back of their TJ's.
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I have not had to change out any springs except for one pair of rear uppers in all of the shocks we've set up. I would not have had to do that if the owner didn't change what he put in the back. The math for a tuner is pretty basic, so they should be much closer than maybe once they have corner weights and uptravel numbers.
 
mrblaine said:
I have not had to change out any springs except for one pair of rear uppers in all of the shocks we've set up. I would not have had to do that if the owner didn't change what he put in the back. The math for a tuner is pretty basic, so they should be much closer than maybe once they have corner weights and uptravel numbers.
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Right....so its the same on mine and that's probably because my tuner prefers to run lighter when possible. We are on the same page. I just find it comical that I can't get a single person on this website to post their rates for some reason. Like its the secret to how they get their wife off or something :ROFLMAO: . Never realized that it was such a tightly guarded secret.
 
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Rock Toy said:
Right....so its the same on mine and that's probably because my tuner prefers to run lighter when possible. We are on the same page. I just find it comical that I can't get a single person on this website to post their rates for some reason. Like its the secret to how they get their wife off or something :ROFLMAO: . Never realized that it was such a tightly guarded secret.
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I don’t have mine yet and plan to do some weighing and math prior to delivery so I don’t know the rates.

There aren’t that many coilovers on here.
 
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Rock Toy said:
Right....so its the same on mine and that's probably because my tuner prefers to run lighter when possible. We are on the same page. I just find it comical that I can't get a single person on this website to post their rates for some reason. Like its the secret to how they get their wife off or something :ROFLMAO: . Never realized that it was such a tightly guarded secret.
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I don't think it's a secret. It just isn't useful when all you care about is the ride height.
 
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jjvw said:
I don't think it's a secret. It just isn't useful when ask you care about is the ride height.
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You don't know what you are talking about. I can set the ride height with a 150lb spring as easily as will a 300lb spring. I'm asking what other guys are running. Not why. I'll figure out the spring combo and valving for MY Jeep using the resources that I have. I was just curious what others came up with. Its really not that hard of an ask.
 
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Rock Toy said:
Right....so its the same on mine and that's probably because my tuner prefers to run lighter when possible. We are on the same page. I just find it comical that I can't get a single person on this website to post their rates for some reason. Like its the secret to how they get their wife off or something :ROFLMAO: . Never realized that it was such a tightly guarded secret.
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It is not a secret, it just doesn't matter and for the record, your tuner can't really run on the light or heavy side, he can only run on the side that supports the rig at the design height unless he wants to play stupid games with a dual rate and a tender. Springs have one job, to hold the rig at the design height and then stop the coil-over bits from falling off at full extension.
 
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