Nissan 370Z Forum - Rear coilover adjustment very different side to side

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Rear coilover adjustment very different side to side

So I thought I was going to finish this install up tonight, clearly not.

The front ride height is set and even between both sides.

With both rear coil perches adjusted the same, the drivers side is an 1 3/8" higher than the passenger.

Modifications I have made along with the coilovers:
Z1 front upper arms
Voodoo 13 solid rear subframe bushings, all bushings verified to be installed correctly, it is not a case where one side is higher up etc.
Voodoo 13 traction arms
Z1 rear camber arms

Things I have tried so far:
Disconnecting the sway bar
Removing both shocks
Swapping the coil springs and perch/collar from side to side

The only thing I can think of is maybe when I tightened back down the upper arm and lower spring bucket to subframe bolts I didn't do booth sides with the same droop so I might be getting some bushing bind?

http://www.the370z.com/members/sirni...-34-04-pm.jpeg
Passenger side coil assembly

http://www.the370z.com/members/sirni...-34-26-pm.jpeg
Passenger side wheel to fender measurement @ 3 1/4"

http://www.the370z.com/members/sirni...-34-55-pm.jpeg
Drivers side coil assembly (when I was trying to even out the gap)

http://www.the370z.com/members/sirni...-35-22-pm.jpeg
Drivers side wheel to fender measurement # 3 1/2"

I can understand 1/4" to 1/2" difference side to side to achieve same height but not over an inch :confused:

Over an inch difference sounds like alot

What coilovers are these?
Do they have threaded shock bodies in the rear?

Try doing it with a FULL tank of gas.

This issue you're seeing is that the gas tank saddle design lends itself to uneven gas levels at below half to quarter tank

And so with sloshing around one side of the tank will hold more fuel than the other when its gets to a lower level.

I went around this myself :facepalm: and so I remember if I need to make any adjustments to the ride height? it's done on a flat level surface with a full tank of gas.

I hope that makes sense :ugh2:

These are Fortune Auto 500 series coilovers.

The car has 3/4 tank of fuel in it at the moment and it is on level ground. I’ll bring some more fuel to fill it up and try loosening then re-tightening the upper control arms to even out any bushing bind.

Are they set to the same height on both sides? The pics look like they differ. I can tell you from doing around 10 sets of coilovers on the Z the front right (battery side) and Rear left are the "lower/heavier" corners. They are approximately 1/8 to 1/4 inch difference.

THe difference you have is not right in anyway.

Here are my questions.
1. Is the preload set to the exact same amount? (should be set at around 1/4 to 3/8 inch).
2. Are these used? Are the struts in perfect working order and are not blown?
3. Are the spring the same length? Manufacturer may have varied spring heights and maybe messed up here.
4. Do you have any excess weight on the rear of the car. I.e. subs etc.
I have found that every 50 pounds or so lowers the rear approximately an 1/8-1/4 of an inch depending on the spring rate type (8k is typical for rear).

Quote:

Originally Posted by Volk Z (Post 3697564)

Are they set to the same height on both sides? The pics look like they differ. I was attempting to adjust the drivers side lower to match the rear ride height when I discovered the issue. As you can see the adjustment is quite different and I would still need to go lower on the drivers side to get it down another 1/4"I can tell you from doing around 10 sets of coilovers on the Z the front right (battery side) and Rear left are the "lower/heavier" corners. They are approximately 1/8 to 1/4 inch difference.

THe difference you have is not right in anyway.

Here are my questions.
1. Is the preload set to the exact same amount? (should be set at around 1/4 to 3/8 inch).
Preloaded at the same amount or with the shocks completely removed the result is the same

2. Are these used? Are the struts in perfect working order and are not blown?
Coilovers are brand new and both rear shocks are in working order and adjusted to the same length, not sure if this is relevant but they are adjusted as short as possible and provide 5/16" of preload on both sides when the spring perches are adjusted to the passenger side length in the picture above

3. Are the spring the same length? Manufacturer may have varied spring heights and maybe messed up here.
Springs are the same length and were swapped side to side incase one was mislabeled to a higher/lower spring rate

4. Do you have any excess weight on the rear of the car. I.e. subs etc.
I have found that every 50 pounds or so lowers the rear approximately an 1/8-1/4 of an inch depending on the spring rate type (8k is typical for rear).
I do have a sub in the trunk which sits dead center, removing it is easy enough but I can't see that being the cause

I'll go by the car shortly and get some more pictures of how everything sits with the rear coil perches adjusted at the same height.

Sorry for the rotated pics, uploaded them from my phone.

http://www.the370z.com/members/sirni...33eb52c32.jpeg

http://www.the370z.com/members/sirni...46dbc4fa7.jpeg

http://www.the370z.com/members/sirni...e8b0695a5.jpeg

http://www.the370z.com/members/sirni...049a750b5.jpeg

Confirmed all subframe bushings are installed in proper orientation and are flush with chassis

Car is 2 dots away from full (man I hate that fuel gauge)

With both spring perches set to the exact same height I get the below measurements

http://www.the370z.com/members/sirni...e91ffc1e2.jpeg
Passenger side without shock

http://www.the370z.com/members/sirni...72c114df8.jpeg
Drivers side without shock

is the spring seat on the bottom seated right? The difference is too high

Quote:

Originally Posted by Justint5387 (Post 3697703)

is the spring seat on the bottom seated right? The difference is too high

Yep i made sure to double check that too, i had a friend lower the car slowly while i watched the springs.

So then it's the perch you adjusted. You should be able to see where it was or match the side you like for height

Are these gas charged coil-overs?

Also when doing the rear. Check the front measurement to see if it moved.

VolkZ, it's not the perch that's the problem. I can swap the spring/perch assemblies and the result is still the same

Rusty, they are gas charged. The rear is OEM style where the spring and shock are separate.

It's been shitty weather here this week so I haven't gotten a chance to put the rear shocks back in, loosen and retighten all the bolts and go pot hole hunting to settle the suspension.

Quote:

Originally Posted by sirnixalot (Post 3697862)

Time to trade her in then...

No idea man, trying to diagnose over the comp is pretty tough. I hope you figure it out.

Quote:

Originally Posted by Volk Z (Post 3697949)

Time to trade her in then...

No idea man, trying to diagnose over the comp is pretty tough. I hope you figure it out.

:icon18: yeah remote troubleshooting is rough

I'll figure it out eventually I guess and I'll be sure to report back when I do.

Quote:

Originally Posted by sirnixalot (Post 3697862)

Can you check the gas pressure in each shock?