Nissan Z Lowered Suspension Questions

[FSUZ33]

And one more question, while we're talking about suspension arms.

Coilovers are next on my list. With those I'd like the SPL or NISMO front camber arms, but not sure on the rear.
The coilovers I'm looking at are all divorced, so no other suspension parts are necessary.
Plan to lower 0.75" - 1".

1. Will changing the front control arms be enough to give me the adjustability I need/want? Could I, or should I change anything else on the front?

2. On the rear I have no clue what to change, if anything. SPL/NISMO have rear camber arms, so I ASSUME those would be a good get. There are seemingly 8 other "arms" on the rear and I don't know anything about what affects what. Like if I change one thing but don't change another it's no bueno.

 

[OptionZero]

Can someone explain to me why wheel offset or spacer thickness differs based on the ride height?
Example: At stock height I can run "X"mm spacers, but if lowered I can run "Y"mm spacers.

A spacer pushes the wheel “out” toward the fender. Bigger spacer, closer to the fender, more likely to rub during compression

same thing when you go with lower offset wheels

 

[OptionZero]

And one more question, while we're talking about suspension arms.

Coilovers are next on my list. With those I'd like the SPL or NISMO front camber arms, but not sure on the rear.
The coilovers I'm looking at are all divorced, so no other suspension parts are necessary.
Plan to lower 0.75" - 1".

1. Will changing the front control arms be enough to give me the adjustability I need/want? Could I, or should I change anything else on the front?

2. On the rear I have no clue what to change, if anything. SPL/NISMO have rear camber arms, so I ASSUME those would be a good get. There are seemingly 8 other "arms" on the rear and I don't know anything about what affects what. Like if I change one thing but don't change another it's no bueno.

there are three arms to replace, SPL just provides different options:

Camber Arm:
SPL offers a dogbone or a billet version. The billet version is more expensive bc it is a newer, stronger design. For anything short of a hardcore track car, go with dogbone. As the name implies, this arm adjusts cambee

Toe Arm:
Here is where divorced/true coilover differs
If you have a divorced (OEM style), you need the Mid-link. This style retains a spring bucket, which is also provides height adjustment. On the latest design, the bucket isn’t a bucket, it’s a cone the faces upward, for lack of a more technical description

SPL also will include an adjustable top mount so the spring stays centered. It’s the conical thing in their picture,

BIG NOTE:
https://www.splparts.com/products/370z-g37-rear-mid-links.html

See this link. If you get this midlink you MUST use springs with a 60mm inner diameter. This is a common size, and SPL can you any spring rate from Swift to use with this part

if you have true type coilovers, do not get the mid link, get the Rear Toe Link. As with the camber arm, they offer dogbone and billet versions which do the same thing. Billet is just for hardcores.

obviously, midlink/toe arm adjusts toe

3. Traction arm

The rear traction arm only comes in one style. This arm affects both camber and toe. Think of the rear suspension as a triangle formed by these three arms. If you adjust the lengths of two of the arms you may need to adjust the third. This is the third. Get this arm so you alignment tech can get everything set correctly, as these arms will give you essentially limitless adjustment.

FINALLY:
the OEM set up uses eccentric bolts on stock arms to adjust camber and toe arm slightly. You no longer need these bc you have adjustable length arms. The stock eccentric bolts will “slip” eventually, screwing up your alignment. Get the eccentric lockout kit, which replace the stock eccentric bolts with ones that won’t move

https://www.splparts.com/products/eccentric-lockout-kit-for-nissan-370z-g37.html

it’s a big investment but this is the correct way to lower your car whether for street or track. Your alignment tech will miss you and you will have limitless wheel fitment options. The Z already has massive fender space, now you can rock aggressive wheels as you please.

camber isn’t the tire killer, it causes uneven wear but toe is what murders tires. Adjustable arms let you dial that out

 

[FSUZ33]

A spacer pushes the wheel “out” toward the fender. Bigger spacer, closer to the fender, more likely to rub during compression

same thing when you go with lower offset wheels

My thought...and I seem to be wrong, but here goes...

Assuming no one's changed any suspension geometry, let's say you drop a car 2" and swap to low offset wheels. Although they're tucked and right on the edge, there's no scrub.
I have the same car at stock height and install those same offset wheels and tires. I hit a bump and my suspension compresses 2" (the same position you're in rolling down the highway). Do I scrub?

If yes, what's the difference between your car lowered 2" and mine when I hit a bump that compresses my suspension 2"?
I realize camber decreases as the suspension is compressed, but whether it's a car lowered 2" or a car at stock height with the suspension compressed 2", the camber angle and position of the suspension (and wheel/tire) is identical at that point. My brain wants to think it is anyway. \

I literally want to be proved wrong here, as it seems I'm wrong but can't grasp it yet.

 

[FSUZ33]

there are three arms to replace, SPL just provides different options:

Camber Arm:
SPL offers a dogbone or a billet version. The billet version is more expensive bc it is a newer, stronger design. For anything short of a hardcore track car, go with dogbone. As the name implies, this arm adjusts cambee

Toe Arm:
Here is where divorced/true coilover differs
If you have a divorced (OEM style), you need the Mid-link. This style retains a spring bucket, which is also provides height adjustment. On the latest design, the bucket isn’t a bucket, it’s a cone the faces upward, for lack of a more technical description

SPL also will include an adjustable top mount so the spring stays centered. It’s the conical thing in their picture,

BIG NOTE:
https://www.splparts.com/products/370z-g37-rear-mid-links.html

See this link. If you get this midlink you MUST use springs with a 60mm inner diameter. This is a common size, and SPL can you any spring rate from Swift to use with this part

if you have tried type coilovers, do not get the mid link, get the Rear Toe Link. As with the camber arm, they offer dogbone and billet versions which do the same thing. Billet is just for hardcores.

obviously, midlink/toe arm adjusts toe

3. Traction arm

The rear traction arm only comes in one style. This arm affects both camber and toe. Think of the rear suspension as a triangle formed by these three arms. If you adjust the lengths of two of the arms you may need to adjust the third. This is the third. Get this arm so you alignment tech can get everything set correctly, as these arms will give you essentially limitless adjustment.

FINALLY:
the OEM set up uses eccentric bolts on stock arms to adjust camber and toe arm slightly. You no longer need these bc you have adjustable length arms. The stock eccentric bolts will “slip” eventually, screwing up your alignment. Get the eccentric lockout kit, which replace the stock eccentric bolts with ones that won’t move

https://www.splparts.com/products/eccentric-lockout-kit-for-nissan-370z-g37.html

it’s a big investment but this is the correct way to lower your car whether for street or track. Your alignment tech will miss you and you will have limitless wheel fitment options. The Z already has massive fender space, now you can rock aggressive wheels as you please.

camber isn’t the tire killer, it causes uneven wear but toe is what murders tires. Adjustable arms let you dial that out

This is exactly the info I was looking for.
Thank you!!!

 

[OptionZero]

My thought...and I seem to be wrong, but here goes...

Assuming no one's changed any suspension geometry, let's say you drop a car 2" and swap to low offset wheels. Although they're tucked and right on the edge, there's no scrub.
I have the same car at stock height and install those same offset wheels and tires. I hit a bump and my suspension compresses 2" (the same position you're in rolling down the highway). Do I scrub?

If yes, what's the difference between your car lowered 2" and mine when I hit a bump that compresses my suspension 2"?
I realize camber decreases as the suspension is compressed, but whether it's a car lowered 2" or a car at stock height with the suspension compressed 2", the camber angle and position of the suspension (and wheel/tire) is identical at that point. My brain wants to think it is anyway. \

I literally want to be proved wrong here, as it seems I'm wrong but can't grasp it yet.

maybe I misunderstood your question, I thought you were asking about spacer vs no spacer, not lowered vs not lowered

you are correct that on the whiteboard, if the alignment is set such that the tire clears, the same settings with more height also will not rub

but real world, alot folks slap on lowering springs, don’t correct the the alignment bc they don’t wanna buy FUCAs, and then complain about rubbing.

as long as your car is set at the height you want when dialing alignment for wheel figment, you should be good. Bearing in mind, nothing replicates fully the real world of bumps at speed which may, under random circumstances, cause more stuff to move or flex. Like your lip hitting a berm causing the bumper and fender to flex. But those are specific disasters unlikely to occur for street driving

 

[FSUZ33]

maybe I misunderstood your question, I thought you were asking about spacer vs no spacer, not lowered vs not lowered

you are correct that on the whiteboard, if the alignment is set such that the tire clears, the same settings with more height also will not rub

but real world, alot folks slap on lowering springs, don’t correct the the alignment bc they don’t wanna buy FUCAs, and then complain about rubbing.

as long as your car is set at the height you want when dialing alignment for wheel figment, you should be good. Bearing in mind, nothing replicates fully the real world of bumps at speed which may, under random circumstances, cause more stuff to move or flex. Like your lip hitting a berm causing the bumper and fender to flex. But those are specific disasters unlikely to occur for street driving

Yeah, I guess I should have been more clear.

Let's say we both have completely unmodified '24 NISMOs and we're both buying spacers.
You're lowered 1.5" and I'm stock height.
-> !This is an example, so no one burn me if my sizes are off!
The concensus is you could go with 20mm spacers because you're lowered. But I can only go 15mm because 20mm would scrub, because I'm not lowered.

Am I making that scenario up, or is that true? If it's true I don't understand why it's true.

Hopefully that's clearer.
That said, I appreciate your effort already.

 

[OptionZero]

Yeah, I guess I should have been more clear.

Let's say we both have completely unmodified '24 NISMOs and we're both buying spacers.
You're lowered 1.5" and I'm stock height.
-> !This is an example, so no one burn me if my sizes are off!
The concensus is you could go with 20mm spacers because you're lowered. But I can only go 15mm because 20mm would scrub, because I'm not lowered.

Am I making that scenario up, or is that true? If it's true I don't understand why it's true.

Hopefully that's clearer.
That said, I appreciate your effort already.

throw the spacers in the garbage, buy better specd wheels, slap on all the coilovers and arms, and dont worry about it?

 

[Gadgetech]

I‘m curious how much people are scraping upfront with lowered cars? I already scrape around town on occasion with a stock height car. I think whats scraping is either the flap in front of the tires or the black plastic aero.

 

[FSUZ33]

I haven't scraped yet, although I did pull up too far and tap a parking curb/stop thing. Generally pretty careful. And driving low-slung cars in the same city for many years has taught me areas and entrances to avoid. Plan on coilovers, so I assume the streak will come to an end at that point.