I had the same problem call up Pfadt and they faxed me the factory settings 
Need Pfadt Coilover preload spring length
Thread Starter
Burning Brakes
Joined: Jul 2006
Posts: 824
Likes: 3
From: Houston, Tx.....'05 Corvette M6 LS3 Magnuson Heartbeat
Need Pfadt Coilover preload spring length
I just discovered my recently installed (used) Pfdat coilovers have different spring preload adjustments. The overall ride height adjustable coilover lengths are the same for both rear shocks (~9"), but the spring lengths vary 1/2" (6" vs. 6 1/2").
Can someone tell me what the length from the top of the spring to the bottom of the spring (top of the spring perch) factory setting for both rear coilovers? And does that same dimension also apply to the front coilovers?
Can someone tell me what the length from the top of the spring to the bottom of the spring (top of the spring perch) factory setting for both rear coilovers? And does that same dimension also apply to the front coilovers?
Melting Slicks
Joined: Sep 2005
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From: merritt island fl
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2016 C1 of the Year Finalist
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What's really important is the ride height at each corner of the car. That's all the adjusters change. If the ride heights are equal, left to right, then all is well. If not equal, adjust accordingly.
Thread Starter
Burning Brakes
Joined: Jul 2006
Posts: 824
Likes: 3
From: Houston, Tx.....'05 Corvette M6 LS3 Magnuson Heartbeat
"The spring perches adjust the shocks sag/spring pre-load". (ride height is a different adjustment, my question is about the preload).
The instructions go on to read :
"Do not move spring perch (factory adjustment) unless the car is a light weight race car. Only adjust after exhausting body length perches adjustment range."
What I'm am trying to do is verify what the factory pre-load dimension is for both the front and rear coilovers (when purchased new). If someone has a set yet to be installed, I was hoping they could take a measurement for me so I can compare my current setting to factory settings.
Melting Slicks
Joined: May 2008
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From: Fresno Ca
Melting Slicks
Joined: Sep 2005
Posts: 2,670
Likes: 134
From: merritt island fl
C1 of Year Finalist (stock) 2019
2016 C1 of the Year Finalist
2015 C2 of the Year Finalist
Did you get an answer from Pfadt?
To me, it looks like a regular adjustment collar and some spacers on the top. Sounds like the spacers give a rough adjustment and you need to use the collars for final ride height adjustment. If so, adjust the collars to give approx the same uninstalled pre-load, then adjust ride height as necessary after install. BTW, if you are a SERIOUS racer (not a bling thing) you want to use the collars to give equal weight across the car. This will sometimes result in unequal ride height appearance, especially if you are comparing the fender cutout appearance.
To me, it looks like a regular adjustment collar and some spacers on the top. Sounds like the spacers give a rough adjustment and you need to use the collars for final ride height adjustment. If so, adjust the collars to give approx the same uninstalled pre-load, then adjust ride height as necessary after install. BTW, if you are a SERIOUS racer (not a bling thing) you want to use the collars to give equal weight across the car. This will sometimes result in unequal ride height appearance, especially if you are comparing the fender cutout appearance.
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Thread Starter
Burning Brakes
Joined: Jul 2006
Posts: 824
Likes: 3
From: Houston, Tx.....'05 Corvette M6 LS3 Magnuson Heartbeat
I got a reply from Aaron with Pfadt,
"We measure from the top of the body (silver part where the shaft enters) to the bottom of the spring perch locking ring. The measurement I use to set them in our assembly is 4 5/8". Our measurement between locking rings is 1 5/8". That is our factory starting point."
Thanks Aaron, that's what I needed.
"We measure from the top of the body (silver part where the shaft enters) to the bottom of the spring perch locking ring. The measurement I use to set them in our assembly is 4 5/8". Our measurement between locking rings is 1 5/8". That is our factory starting point."
Thanks Aaron, that's what I needed.
