Coil-over Suspension Question
Thread Starter
Racer
Joined: Jul 2013
Posts: 451
Likes: 120
From: Scotts Valley Ca
Coil-over Suspension Question
I have a 03z that has PFADT coil overs installed on it. The ride is nice but soft it like a Cadillac really and not a sports car feel.
I would like to lower the car more since it sit's rather high ride height wise in my opinion. I have seen people on here with their cars
basically on the ground and they look amazing. The question I have is....... how can you lower the car that far and not have your tires
rub the inner wheel-wells? I pulled my wheels off the other day to take a look at lowering the car (rear) and noticed I have some rub marks already so I just left it be for the time being and thought I would ask you all for input first. Are there other adjustment I should make first?
Thanks for any input in advance.
I would like to lower the car more since it sit's rather high ride height wise in my opinion. I have seen people on here with their cars
basically on the ground and they look amazing. The question I have is....... how can you lower the car that far and not have your tires
rub the inner wheel-wells? I pulled my wheels off the other day to take a look at lowering the car (rear) and noticed I have some rub marks already so I just left it be for the time being and thought I would ask you all for input first. Are there other adjustment I should make first?
Thanks for any input in advance.
Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,565
Likes: 7,241
From: CT
I am not familiar with the pfadt setup, but they more than like have adjustable rebound setting on all four corners which would allow you to make the soft caddy feel go away.
As for ride height. How are the roads and driveways where you live? I run ride tech hq in Connecticut where the roads are typically good, but elevation changes are common. I run my car at the top most height setting to keep from scraping the nose. For me, function trumps appearance.
As for ride height. How are the roads and driveways where you live? I run ride tech hq in Connecticut where the roads are typically good, but elevation changes are common. I run my car at the top most height setting to keep from scraping the nose. For me, function trumps appearance.
Racer
Joined: Dec 2017
Posts: 331
Likes: 74
From: Florida
Not all coil overs have the same spring rate. Generally when you're drastically low like how you're describing, youll need stiffer springs so your tires don't have those problems of rubbing or improperly tucking into the wheel well. A lot of these systems have that in mind though and might be a spanner wrench adjustment away as long as the shocks are matched as well.
Last edited by 02torchred; Mar 16, 2020 at 01:19 AM.
Thread Starter
Racer
Joined: Jul 2013
Posts: 451
Likes: 120
From: Scotts Valley Ca
Thanks for the replies. I checked the compression settings and the have 16 clicks of adjustment. They were set at 2 clicks so yeah super soft. I am gong to play with the settings and see if I can get away with lowering the rear a little more.
Would increasing the pre load on the springs help? I checked and they have been set very loose. When you raise the car the springs can be rotated so there really is no pre-load on them at all. Any suggestions on how much pre-load would be a good start?
Would increasing the pre load on the springs help? I checked and they have been set very loose. When you raise the car the springs can be rotated so there really is no pre-load on them at all. Any suggestions on how much pre-load would be a good start?
Last edited by Sportsman2003; Mar 15, 2020 at 02:41 PM.
Drifting
Joined: Aug 2014
Posts: 1,626
Likes: 174
From: North pole
I have a 03z that has PFADT coil overs installed on it. The ride is nice but soft it like a Cadillac really and not a sports car feel.
I would like to lower the car more since it sit's rather high ride height wise in my opinion. I have seen people on here with their cars
basically on the ground and they look amazing. The question I have is....... how can you lower the car that far and not have your tires
rub the inner wheel-wells? I pulled my wheels off the other day to take a look at lowering the car (rear) and noticed I have some rub marks already so I just left it be for the time being and thought I would ask you all for input first. Are there other adjustment I should make first?
Thanks for any input in advance.
I would like to lower the car more since it sit's rather high ride height wise in my opinion. I have seen people on here with their cars
basically on the ground and they look amazing. The question I have is....... how can you lower the car that far and not have your tires
rub the inner wheel-wells? I pulled my wheels off the other day to take a look at lowering the car (rear) and noticed I have some rub marks already so I just left it be for the time being and thought I would ask you all for input first. Are there other adjustment I should make first?
Thanks for any input in advance.
Last edited by 04zjimc; Mar 15, 2020 at 10:10 PM.
Racer
Joined: Dec 2017
Posts: 331
Likes: 74
From: Florida
Some companies do not recommend excessive pre-loading, and sometimes it doesn't even affect the spring rate with linear-rate springs.
(Pre-load for BC coilovers is measured by turning the upper lock nut hand tight until the spring stops moving up and down. Spinning around is fine. The supplied spanner wrenches are 4mm thick so you use that to tighten it that distance with the tool and then lock it in place)
The lowest lock nut near the base shock perch controls ride height, so you might want to mess with that instead. If that setup has one, it will be below the two upper lock nuts below the springs.
The clicks are for shock valving, which does not affect spring rate, only spring dampening.
Both will affect ride quality and handling, but only spring rate/ride height will keep the wheels from rubbing or improperly tucking into the wheel-wells when lowered a ton or slammed.
All of this is dependent on how you want the ride to be, how low, and how much, if any, rubbing you get.
(Pre-load for BC coilovers is measured by turning the upper lock nut hand tight until the spring stops moving up and down. Spinning around is fine. The supplied spanner wrenches are 4mm thick so you use that to tighten it that distance with the tool and then lock it in place)
The lowest lock nut near the base shock perch controls ride height, so you might want to mess with that instead. If that setup has one, it will be below the two upper lock nuts below the springs.
The clicks are for shock valving, which does not affect spring rate, only spring dampening.
Both will affect ride quality and handling, but only spring rate/ride height will keep the wheels from rubbing or improperly tucking into the wheel-wells when lowered a ton or slammed.
All of this is dependent on how you want the ride to be, how low, and how much, if any, rubbing you get.
Last edited by 02torchred; Mar 16, 2020 at 01:53 AM.
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Melting Slicks
Joined: Feb 2007
Posts: 3,297
Likes: 398
From: Raleigh Suburbs
Some companies do not recommend excessive pre-loading, and sometimes it doesn't even affect the spring rate with linear-rate springs.
(Pre-load for BC coilovers is measured by turning the upper lock nut hand tight until the spring stops moving up and down. Spinning around is fine. The supplied spanner wrenches are 4mm thick so you use that to tighten it that distance with the tool and then lock it in place)
The lowest lock nut near the base shock perch controls ride height, so you might want to mess with that instead. If that setup has one, it will be below the two upper lock nuts below the springs.
The clicks are for shock valving, which does not affect spring rate, only spring dampening.
Both will affect ride quality and handling, but only spring rate/ride height will keep the wheels from rubbing or improperly tucking into the wheel-wells when lowered a ton or slammed.
All of this is dependent on how you want the ride to be, how low, and how much, if any, rubbing you get.
(Pre-load for BC coilovers is measured by turning the upper lock nut hand tight until the spring stops moving up and down. Spinning around is fine. The supplied spanner wrenches are 4mm thick so you use that to tighten it that distance with the tool and then lock it in place)
The lowest lock nut near the base shock perch controls ride height, so you might want to mess with that instead. If that setup has one, it will be below the two upper lock nuts below the springs.
The clicks are for shock valving, which does not affect spring rate, only spring dampening.
Both will affect ride quality and handling, but only spring rate/ride height will keep the wheels from rubbing or improperly tucking into the wheel-wells when lowered a ton or slammed.
All of this is dependent on how you want the ride to be, how low, and how much, if any, rubbing you get.
Usually the setup takes this into account...won't necessarily be the same from car to car...
What was mentioned in regards to the stiffness of the springs is also good science - I believe this takes the place of technical 'preload' which you are referring to.
Drifting
Joined: Dec 2000
Posts: 1,255
Likes: 50
From: Clayton, NC north carolina
just a suggestion.... get a set of LG drop spindles..... then you can have your "look" without compromising proper suspension geometry. about the lowest i would go is having your lower control arms parallel with the ground..... with that said ...most coilovers you can change ride height by threading the lower mount further up the shock tube.