Coilover lowering Question.
Thread Starter
Drifting
Joined: Oct 2011
Posts: 1,980
Likes: 10
From: Crook County
Coilover lowering Question.
Had a question, I got a set of Gen 1 Black bodied Pfadt coilovers on my C5Z. After putting on my 18/19 wheels I have some gap I would like to close up a bit. My tires are 275/35/18 MT Street Comps and my Rears are 305/35/19 NT05R's... Now my Coilovers are set up for the proper ride, I just want to physically lower the car 1.25 all around...
Now do I just have to loosen the lock nut on the bottom and back it out to the amount of threads I want then use the larger spanner wrench and run the the perch nut down with the top lock nut still locked. I want to sink the threads into the lower cup without actually moving the spring. Just want to thread the body down. OR do i have to unbolt the bottom of the coilover and spin the cup upwards....
also am I correct is saying for every 1/4" worth of thread is worth a 1/2" of ride height" So hypothetically if I sink a 1/2" worth of threads into the body It would drop my ride height 1"?
This is how the car sits now
Now do I just have to loosen the lock nut on the bottom and back it out to the amount of threads I want then use the larger spanner wrench and run the the perch nut down with the top lock nut still locked. I want to sink the threads into the lower cup without actually moving the spring. Just want to thread the body down. OR do i have to unbolt the bottom of the coilover and spin the cup upwards....
also am I correct is saying for every 1/4" worth of thread is worth a 1/2" of ride height" So hypothetically if I sink a 1/2" worth of threads into the body It would drop my ride height 1"?
This is how the car sits now
Last edited by Breze84; May 5, 2015 at 08:24 AM.
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looks like those are similar to how my lg's are and if so, in order to make proper ride height changes you have to loosen the lower locknut, unbolt the bottom of the coilover from the lca, and then screw the lower body of the coilover onto the threaded sleeve... to my understanding if you try to do screw the threaded sleeve into the lower body with everything else connected you risk unscrewing the coilover internally
Last edited by StingrayRebel; May 5, 2015 at 09:53 AM.
Thread Starter
Drifting
Joined: Oct 2011
Posts: 1,980
Likes: 10
From: Crook County
looks like those are similar to how my lg's are and if so, in order to make proper ride height changes you have to loosen the lower locknut, unbolt the bottom of the coilover from the lca, and then screw the lower body of the coilover onto the threaded sleeve... to my understanding if you try to do screw the threaded sleeve into the lower body with everything else connected you risk unscrewing the coilover internally
...
Le Mans Master
Joined: May 2007
Posts: 5,393
Likes: 17
From: Belleville Mich.
I would disconnect the C/over from the bottom.
To be able to know, how far the threaded body sets into the bottom cup.
You sure wouldn't ever want the threaded body to be about to come out of the bottom cup =
extreme failure
Measure from the bottom of Spring Perch locking ring to the top of the bottom locking ring (against the lower cup.)
Now you have a reference point to where you are starting at.
Loosen the bottom Cup locking ring & run it up enough (to be out of the way) to be able to screw the bottom cup upwards until the threads bottom out at the bottom of the cup & then back the cup away from bottoming out by one complete turn.
Run the Cup locking ring back down against the lower cup & remeasure.
By your measurement (before & after) you know how far the threaded body was threaded into the cup by subtraction.
1/2" of ride height =1/4" of thread.
Your objective 1.25" lowered would equal 5/8"
Depending to where the threaded body was setting inside the cup (reference point would dictate to screwing the cup up or down onto the threaded body.
If by chance the The reference point threaded body was bottomed out in the cup to begin with.
Loosen the top spring perch locking ring & turn the top spring perch down 5/8" to get the 1.25" drop that you are seeking.
To be able to know, how far the threaded body sets into the bottom cup.
You sure wouldn't ever want the threaded body to be about to come out of the bottom cup =
extreme failureMeasure from the bottom of Spring Perch locking ring to the top of the bottom locking ring (against the lower cup.)
Now you have a reference point to where you are starting at.
Loosen the bottom Cup locking ring & run it up enough (to be out of the way) to be able to screw the bottom cup upwards until the threads bottom out at the bottom of the cup & then back the cup away from bottoming out by one complete turn.
Run the Cup locking ring back down against the lower cup & remeasure.
By your measurement (before & after) you know how far the threaded body was threaded into the cup by subtraction.
1/2" of ride height =1/4" of thread.
Your objective 1.25" lowered would equal 5/8"
Depending to where the threaded body was setting inside the cup (reference point would dictate to screwing the cup up or down onto the threaded body.
If by chance the The reference point threaded body was bottomed out in the cup to begin with.
Loosen the top spring perch locking ring & turn the top spring perch down 5/8" to get the 1.25" drop that you are seeking.
Thread Starter
Drifting
Joined: Oct 2011
Posts: 1,980
Likes: 10
From: Crook County
I would disconnect the C/over from the bottom.
To be able to know, how far the threaded body sets into the bottom cup.
You sure wouldn't ever want the threaded body to be about to come out of the bottom cup = extreme failure
Measure from the bottom of Spring Perch locking ring to the top of the bottom locking ring (against the lower cup.)
Now you have a reference point to where you are starting at.
Loosen the bottom Cup locking ring & run it up enough (to be out of the way) to be able to screw the bottom cup upwards until the threads bottom out at the bottom of the cup & then back the cup away from bottoming out by one complete turn.
Run the Cup locking ring back down against the lower cup & remeasure.
By your measurement (before & after) you know how far the threaded body was threaded into the cup by subtraction.
1/2" of ride height =1/4" of thread.
Your objective 1.25" lowered would equal 5/8"
Depending to where the threaded body was setting inside the cup (reference point would dictate to screwing the cup up or down onto the threaded body.
If by chance the The reference point threaded body was bottomed out in the cup to begin with.
Loosen the top spring perch locking ring & turn the top spring perch down 5/8" to get the 1.25" drop that you are seeking.
To be able to know, how far the threaded body sets into the bottom cup.
You sure wouldn't ever want the threaded body to be about to come out of the bottom cup =
extreme failureMeasure from the bottom of Spring Perch locking ring to the top of the bottom locking ring (against the lower cup.)
Now you have a reference point to where you are starting at.
Loosen the bottom Cup locking ring & run it up enough (to be out of the way) to be able to screw the bottom cup upwards until the threads bottom out at the bottom of the cup & then back the cup away from bottoming out by one complete turn.
Run the Cup locking ring back down against the lower cup & remeasure.
By your measurement (before & after) you know how far the threaded body was threaded into the cup by subtraction.
1/2" of ride height =1/4" of thread.
Your objective 1.25" lowered would equal 5/8"
Depending to where the threaded body was setting inside the cup (reference point would dictate to screwing the cup up or down onto the threaded body.
If by chance the The reference point threaded body was bottomed out in the cup to begin with.
Loosen the top spring perch locking ring & turn the top spring perch down 5/8" to get the 1.25" drop that you are seeking.
Beautiful
I surly do appreciate taking the time to write that. Going to be knocking this out Friday night, Will post pics afterwards then I will let it settle and take it for a alignment... 
Last edited by Breze84; May 5, 2015 at 03:18 PM.
Race Director
Joined: Apr 2007
Posts: 11,150
Likes: 889
From: South Western Ontario
First off, is your tie rod bent in that second picture. It certainly doesn't look straight which is a bad thing.
I believe Pfadt's instructions were to just take the weight off the suspension and screw the shock body down into the mounting cup to lower the car. But, people have had the top mount come loose from doing that. So, it's recommended to take them either partially or fully off to adjust.
You're shortening the coilover assembly. There is no need to worry the thread engagement in the lower mounting cup since you'll be adding more than what you have now.
So, just move the mounting cup up the body about 1/2 the amount you want it to lower and see what ride height you get.
I believe Pfadt's instructions were to just take the weight off the suspension and screw the shock body down into the mounting cup to lower the car. But, people have had the top mount come loose from doing that. So, it's recommended to take them either partially or fully off to adjust.
You're shortening the coilover assembly. There is no need to worry the thread engagement in the lower mounting cup since you'll be adding more than what you have now.
So, just move the mounting cup up the body about 1/2 the amount you want it to lower and see what ride height you get.
Thread Starter
Drifting
Joined: Oct 2011
Posts: 1,980
Likes: 10
From: Crook County
First off, is your tie rod bent in that second picture. It certainly doesn't look straight which is a bad thing.
I believe Pfadt's instructions were to just take the weight off the suspension and screw the shock body down into the mounting cup to lower the car. But, people have had the top mount come loose from doing that. So, it's recommended to take them either partially or fully off to adjust.
You're shortening the coilover assembly. There is no need to worry the thread engagement in the lower mounting cup since you'll be adding more than what you have now.
So, just move the mounting cup up the body about 1/2 the amount you want it to lower and see what ride height you get.
I believe Pfadt's instructions were to just take the weight off the suspension and screw the shock body down into the mounting cup to lower the car. But, people have had the top mount come loose from doing that. So, it's recommended to take them either partially or fully off to adjust.
You're shortening the coilover assembly. There is no need to worry the thread engagement in the lower mounting cup since you'll be adding more than what you have now.
So, just move the mounting cup up the body about 1/2 the amount you want it to lower and see what ride height you get.
