Rear coilover adjustment very different side to side

sirnixalot · 10-02-2017, 11:04 PM

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?

Passenger side coil assembly

Passenger side wheel to fender measurement @ 3 1/4"

Drivers side coil assembly (when I was trying to even out the gap)

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

OptionZero · 10-03-2017, 12:12 AM

Over an inch difference sounds like alot

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

Trips · 10-03-2017, 12:25 AM

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

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

sirnixalot · 10-03-2017, 08:07 AM

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.

Volk Z · 10-03-2017, 10:34 AM

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).

sirnixalot · 10-03-2017, 11:11 AM

Quote:

Originally Posted by Volk Z

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.

sirnixalot · 10-03-2017, 12:44 PM

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

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

Passenger side without shock

Drivers side without shock

Justint5387 · 10-03-2017, 04:58 PM

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

sirnixalot · 10-03-2017, 05:20 PM

Quote:

Originally Posted by Justint5387

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.

Volk Z · 10-03-2017, 09:41 PM

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

Rusty · 10-03-2017, 10:42 PM

Are these gas charged coil-overs?

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

sirnixalot · 10-04-2017, 09:20 AM

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.

Volk Z · 10-04-2017, 02:20 PM

Quote:

Originally Posted by sirnixalot

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.

Time to trade her in then...

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

sirnixalot · 10-04-2017, 02:23 PM

Quote:

Originally Posted by Volk Z

Time to trade her in then...

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

yeah remote troubleshooting is rough

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

Rusty · 10-04-2017, 03:14 PM

Quote:

Originally Posted by sirnixalot

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.

Can you check the gas pressure in each shock?

10-02-2017, 11:04 PM	#1 (permalink)
sirnixalot Track Member Join Date: May 2017 Location: Cayman Islands Posts: 685 Drives: 2010 370Z Rep Power: 57454	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? Passenger side coil assembly Passenger side wheel to fender measurement @ 3 1/4" Drivers side coil assembly (when I was trying to even out the gap) 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 __________________ 2010 Sport - LS3 swap loading 2012 Frontier - BTWTuning VK56DE swap

10-03-2017, 12:12 AM	#2 (permalink)
OptionZero A True Z Fanatic Join Date: Apr 2011 Location: Sacramento Posts: 3,225 Drives: 15 370Z Nismo 6MT Rep Power: 214100	Over an inch difference sounds like alot What coilovers are these? Do they have threaded shock bodies in the rear? __________________ OptionZero Build Thread

10-03-2017, 12:25 AM	#3 (permalink)
Trips Administrator Join Date: May 2009 Location: Disneyland, Ca Posts: 8,730 Drives: 🔰 Rep Power: 10	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 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 JARblue and Rusty like this. __________________

10-03-2017, 08:07 AM	#4 (permalink)
sirnixalot Track Member Join Date: May 2017 Location: Cayman Islands Posts: 685 Drives: 2010 370Z Rep Power: 57454	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. __________________ 2010 Sport - LS3 swap loading 2012 Frontier - BTWTuning VK56DE swap Last edited by sirnixalot; 10-03-2017 at 08:44 AM.

10-03-2017, 10:34 AM	#5 (permalink)
Volk Z A True Z Fanatic Join Date: Aug 2011 Location: Laguna Beach, CA Posts: 2,214 Drives: Nismo Z Rep Power: 3066	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). wideglideleon likes this. __________________ AMUSE * TOMEI * STILLEN * CRAFTSQUARE RECARO * 3M * TOP SECRET * SLICKCARBON

10-03-2017, 12:44 PM	#7 (permalink)
sirnixalot Track Member Join Date: May 2017 Location: Cayman Islands Posts: 685 Drives: 2010 370Z Rep Power: 57454	Sorry for the rotated pics, uploaded them from my phone. 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 Passenger side without shock Drivers side without shock __________________ 2010 Sport - LS3 swap loading 2012 Frontier - BTWTuning VK56DE swap

10-03-2017, 04:58 PM	#8 (permalink)
Justint5387 Base Member Join Date: Aug 2014 Location: Bay Area, CA Posts: 188 Drives: 2016 370z Silver 6MT Rep Power: 12	is the spring seat on the bottom seated right? The difference is too high

10-03-2017, 09:41 PM	#10 (permalink)
Volk Z A True Z Fanatic Join Date: Aug 2011 Location: Laguna Beach, CA Posts: 2,214 Drives: Nismo Z Rep Power: 3066	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 __________________ AMUSE * TOMEI * STILLEN * CRAFTSQUARE RECARO * 3M * TOP SECRET * SLICKCARBON

10-03-2017, 10:42 PM	#11 (permalink)
Rusty Ronin Samurai - Assassin Join Date: Dec 2011 Location: Fayettenam,Pennsyltucky Age: 68 Posts: 35,185 Drives: 2011 Nismo GM 6M Rep Power: 2684437	Are these gas charged coil-overs? Also when doing the rear. Check the front measurement to see if it moved. __________________ 浪人 - 殺し屋 "The Difficult Anytime, The Impossible By Appointment Only" http://www.the370z.com/members-370z-...o-journal.html Last edited by Rusty; 10-03-2017 at 10:46 PM.

10-04-2017, 09:20 AM	#12 (permalink)
sirnixalot Track Member Join Date: May 2017 Location: Cayman Islands Posts: 685 Drives: 2010 370Z Rep Power: 57454	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. __________________ 2010 Sport - LS3 swap loading 2012 Frontier - BTWTuning VK56DE swap

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[FOR SALE] Evo-R Carbon Fiber Side Diffuser/Side Splitter/Side Blades $130 + Shipping	.c2	Parts for sale (Private Classifieds)	16	09-25-2015 01:09 PM
Noisy rear driver side coilover?	RyanWest	Brakes & Suspension	2	04-03-2015 02:27 PM
Coilover Side by Side Video	Highway	Brakes & Suspension	5	05-01-2013 10:22 PM
Coilover Rear Adjustment question	chrischhorn	Brakes & Suspension	0	02-25-2013 04:31 PM
Pic Request - Shine Auto Rear add-on side view with oem side skirts.	atx370z	Exterior & Interior	8	10-22-2010 11:51 AM