Preload on coilover explanation needed

[Bosrudorfer]

I have KTS coils. Had a very good amount of "preload" and the car was stiff.

Yesterday I removed that "preload" and lowered the spring perch so the spring and upper mount have a pinkie finger gap. This is called drooping right?

Is this bad? This is with the car jacked up of course.

I lengthened the assembly to account for the drop but its still to low, so I'm going to raise the preload so that the spring perch sits tight but the spring can still spin freely (<< that's called running no preload right?)

I just want to get full suspension travel and get the rest of the drop from shortening the assembly.

Thanks =D

(And yes I did search)

[onosqv]

From SPL Parts:

Preloading the spring allows more stroke/travel for the shock, which is very important; if the shock stroke/travel is too short you will be constantly hitting the bump stop. However, preloading the spring too much can create problems - it would become easier for the tire to lift off the ground when the weight transfers away from that corner, and it would also effectively increase the spring rate.

So ideally you want to preload the spring to where you get sufficient shock stroke/travel, and get your remaining ride height through the lengthening/shortening the coilover assembly.

For most ppl, you want basically no spring preload, since most of us don't have any equipment to correctly compensate for adjusting all this stuff, usually only done for corner balancing & adjusting bump stops, etc.

Easiest way is to put the coilover upsidedown, turn the lock nut just until it contacts the spring, then do another 1-2 turns. The couple turns keeps the spring from making a "popping" noise when the suspension is at full length.

[naed240sx]

For most ppl, you want basically no spring preload, since most of us don't have any equipment to correctly compensate for adjusting all this stuff, usually only done for corner balancing & adjusting bump stops, etc.

Sorry man, but you are kind of talking out of your *** here. You don't need equipment to add preload in a beneficial way to a car. If you happen to be hitting the bumpstops, you should add preload.

Also, adjusting bumpstops? huh? That's not possible.

Easiest way is to put the coilover upsidedown, turn the lock nut just until it contacts the spring, then do another 1-2 turns. The couple turns keeps the spring from making a "popping" noise when the suspension is at full length.

First of all, why would you adjust preload with the coils off the car? Why would you turn them upside down? None of this is neccesary or helpful. Preload can be adjusted or zeroed just fine with the coils on the car.

To Bosrudorfer: Drooping spring causes accelerated damper wear, and usually affects handling in a negative way. Do not droop unless the height adjustment is as low as it will go. Drooping if the lower mount is not at the lowest possible position is stupid, because lowering via the lower mounts is the only way to lower without affecting how the piston sits in the damper at static height.

Also, you should NEVER droop spring on front coils. Any coilover will go low enough without drooping. Simply remove collars up front if you want to go lower.

Hope this helps.

[Bosrudorfer]

Yep guys that answered all my questions, thanks.

I'm going to move the spring perch up so there is no drooping in the front/rears and get the rest height desire by the lower bracket.

Thanks

[ArticDragon192]

Usually 0 preload is just fine for everyday driving. I run 5mm preload to to stiffen up the coils a bit since I'm running 6/4 rates on my coils.

[onosqv]

Sorry man, but you are kind of talking out of your *** here. You don't need equipment to add preload in a beneficial way to a car. If you happen to be hitting the bumpstops, you should add preload.

Also, adjusting bumpstops? huh? That's not possible.

First of all, why would you adjust preload with the coils off the car? Why would you turn them upside down? None of this is neccesary or helpful. Preload can be adjusted or zeroed just fine with the coils on the car.

To Bosrudorfer: Drooping spring causes accelerated damper wear, and usually affects handling in a negative way. Do not droop unless the height adjustment is as low as it will go. Drooping if the lower mount is not at the lowest possible position is stupid, because lowering via the lower mounts is the only way to lower without affecting how the piston sits in the damper at static height.

Also, you should NEVER droop spring on front coils. Any coilover will go low enough without drooping. Simply remove collars up front if you want to go lower.

Hope this helps.

I was hungry when answering that question dammit :p.

It was easier for me to adjust the coils exactly how I wanted off the car. Just went by the instructions given when I bought the coils, so they weren't even on the car yet. I am not adjust for preload, I'm doing basically zero preload w/ just enough tension to keep the springs in place.

Adjusting bump stops, meant enough preload on the springs to keep you from hitting bump stops. Sure, you could do it w/ trial and error, but I believe there is some sort of better equipment to help you determine this. Sometimes my fingers don't type all the words I'm thinking, sorry.

Sure, you can adjust preload all you want by yourself... but it won't be much accurate or truly beneficial unless you have corner balance scales. I guess it depends on what you are preloading for... I would adjust preload only to balance the car & keep it to a minimal for maximum suspension travel. "Most" of the time you'll be fine w/ a lil preload, but you don't know for sure how much that is affecting your whole setup.

Of course, I'm probably just talking out of my *** again as usual... sorrrryyyy.