PSS10 height adjustment questions
04-07-2013, 11:02 AM
#1
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PSS10 height adjustment questions
Been running the FD recommended lowered height since install in Aug 2011. I believe it to be RS +10 thought not sure. I would like to raise it up about 5mm or so at the rear wheel when loaded. These are novice questions.
- Can I do this by just unloading the suspension on the lift and unlocking the collar rings? Special tools?
- What adjustment do I need for the front to maintain the correct rake? Do I adjust the same number of turns?
04-07-2013, 11:58 AM
#2
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If you have the PSS-10 kit, you should have two tools that come with it - they are to adjust the height adjustment rings. The tools are bronze in color (usually), and look like a hook with a handle.
If you want to fiddle with your ride height, you can adjust all the corners the same amount, that will preserve the rack. Just count the number of turns you make.
The two rings lock on each other, so use the tools to break the lower ring (smaller one) free, and then the top one is ready to be dialed. You have to have the car off the ground with the tires off of course. Remember, the lower the lower perch/ring, the lower the car, so you want to turn the ring so it puts the perch higher.
Be careful on the rear - you have to keep the swaybar clearing the suspension struts, so watch that when adjusting the rears, and double check it when the car is on the ground - you will need to put the car down, roll it a bit to settle, and then lay on the ground and with a light check out the clearances when the suspension is fully down.
cheers,
Mike
If you want to fiddle with your ride height, you can adjust all the corners the same amount, that will preserve the rack. Just count the number of turns you make.
The two rings lock on each other, so use the tools to break the lower ring (smaller one) free, and then the top one is ready to be dialed. You have to have the car off the ground with the tires off of course. Remember, the lower the lower perch/ring, the lower the car, so you want to turn the ring so it puts the perch higher.
Be careful on the rear - you have to keep the swaybar clearing the suspension struts, so watch that when adjusting the rears, and double check it when the car is on the ground - you will need to put the car down, roll it a bit to settle, and then lay on the ground and with a light check out the clearances when the suspension is fully down.
cheers,
Mike
04-07-2013, 12:49 PM
#3
Rennlist Member
Thread Starter
If you have the PSS-10 kit, you should have two tools that come with it - they are to adjust the height adjustment rings. The tools are bronze in color (usually), and look like a hook with a handle.
If you want to fiddle with your ride height, you can adjust all the corners the same amount, that will preserve the rack. Just count the number of turns you make.
The two rings lock on each other, so use the tools to break the lower ring (smaller one) free, and then the top one is ready to be dialed. You have to have the car off the ground with the tires off of course. Remember, the lower the lower perch/ring, the lower the car, so you want to turn the ring so it puts the perch higher.
Be careful on the rear - you have to keep the swaybar clearing the suspension struts, so watch that when adjusting the rears, and double check it when the car is on the ground - you will need to put the car down, roll it a bit to settle, and then lay on the ground and with a light check out the clearances when the suspension is fully down.
cheers,
Mike
If you want to fiddle with your ride height, you can adjust all the corners the same amount, that will preserve the rack. Just count the number of turns you make.
The two rings lock on each other, so use the tools to break the lower ring (smaller one) free, and then the top one is ready to be dialed. You have to have the car off the ground with the tires off of course. Remember, the lower the lower perch/ring, the lower the car, so you want to turn the ring so it puts the perch higher.
Be careful on the rear - you have to keep the swaybar clearing the suspension struts, so watch that when adjusting the rears, and double check it when the car is on the ground - you will need to put the car down, roll it a bit to settle, and then lay on the ground and with a light check out the clearances when the suspension is fully down.
cheers,
Mike
Is the distance changed on the perch the same amount of height changed when back on the wheels? In other words 1:1 ratio.
04-07-2013, 12:55 PM
#4
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And we know a 1/4" alteration in ride height brings how much change in toe? I've never bothered on a 993, as everything I've done has been install-it-and-forget-it. But from what I remember on the torsion bar cars you got toe change to the extent of half the ride height change. Though, rear toe-in on a torsion bar car is much greater than a 993 (or 964). (And of course we never had to consider K-toe.)
04-07-2013, 01:18 PM
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Yes, the perch height is 1:1 with ride height.
Ken, not sure about how this changes the alignment, but I have done this (more than 1/2"), and the owner drove the car for quite a while afterwards with no ill effect or any wear impacts that we could see.
Ideally of course you should redo the corner balancing (assuming it was done originally) and do an alignment, but I think 1/4" on ride will not make that much difference - lets see if someone has some experiences otherwise ...
Cheers,
Mike
Ken, not sure about how this changes the alignment, but I have done this (more than 1/2"), and the owner drove the car for quite a while afterwards with no ill effect or any wear impacts that we could see.
Ideally of course you should redo the corner balancing (assuming it was done originally) and do an alignment, but I think 1/4" on ride will not make that much difference - lets see if someone has some experiences otherwise ...
Cheers,
Mike
04-07-2013, 07:36 PM
#6
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Ken, not sure about how this changes the alignment, but I have done this (more than 1/2"), and the owner drove the car for quite a while afterwards with no ill effect or any wear impacts that we could see.
Ideally of course you should redo the corner balancing (assuming it was done originally) and do an alignment, but I think 1/4" on ride will not make that much difference - lets see if someone has some experiences otherwise ...
Ideally of course you should redo the corner balancing (assuming it was done originally) and do an alignment, but I think 1/4" on ride will not make that much difference - lets see if someone has some experiences otherwise ...
No need to redo a corner balance if everything goes up or down equally. Most street 993s aren't really corner balanced anyway, given you've got preload from the non-adjustable drop links on the rollbars which instantly throw things slightly out of whack once you reattach them.
