Adjusting Separate Spring and Shock Preload BC Coilovers

[@miguelrmusic]

so you load the spring by jacking the control arm? can you also load the spring just by adjusting shock height?

[@jaylonchung9528]

Jacking the control arm allows you to put preload on the spring

[@abenguyen]

Great video, I've been searching for this info everywhere! One question, is this assuming the height has already been adjusted to what I want before adjusting preload? Will preload affect my suspension travel? I have a generous wheel gap after being lowered but am still rubbing on bumps/inclines/etc in the rear if I go faster than even 15mph. Not sure whether I need higher spring rates, to increase the dampening, or increase preload.

[@cougarslayer91]

Abe Nguyen sam3 problem

[@waikiki14]

Shorten or tighten the spring from relaxed/loose condition 5-7mm. That is the average and typical factory preload.

[@fauzanbaihaqy4463]

Alex Bekbau is it for rear or front? Or same?

[@alloutofdonuts3998]

@@fauzanbaihaqy4463 this vid is saying 7-10mm for the rear. The very brief instructions that came with mine (e90 bmw 335xi) said 3-5mm front. Not sure if this differs per car or if that’s the standard for all cars.

[@Dnasty1]

Great vid. I’ve had my bc coilovers on for about a year and want to raise the car. I have the same setup as you showed with the shock separate from the spring. Is it necessary to adjust the shock each time I adjust the ride height or can I just adjust the spring by itself to change ride height?

[@RaceStudio]

the point of taking the shock off prior to adjusting spring height is so the shock and have proper length. i suspect itll jack things up considering as your spring and shock are fighting each other.

[@mhollon11]

Do you have to adjust rear preload everytime you adjust height?

[@slumygoat]

On divorced style rears….yes

[@MostGenericUser]

How about height? all the how to videos are on strut coilovers

[@MrBlahblahblee]

You do the same thing as the video. The only thing that changes between heights is the adjustment on the spring collars. Then you match the length of the strut to the length that it takes to put the lower mount bolt through the hole.

[@joshuaperez1187]

So if I want the car to be lowered more, I need to shorten the shock?

[@alloutofdonuts3998]

How does this work on cars that don’t have a bolt hole like this? My car has a stud w/nut that goes through the lower mount in the lower control arm. Is it possible to just loosen the shock collar and turn the shock until it’s slacked, set preload, then turn the shock body until it’s tight again?

[@Aarejayy]

So if I just wanted to lower the rear without messing with the preload, would I just screw the shock body down in the lower mount and not even mess with the collars on the coil?

[@MostGenericUser]

Want to know this too but seems it's a mystery. no tutoriasl on how to adjust height on rear torsion beam suspension with separate shock and springs. All the ones I find are on strut coilovers

[@Aarejayy]

Yeah I kinda had to figure it out on my own. I pretty much did everything in the video but I adjusted the collars on the spring all the way to the top (I was trying to max out my coilovers in the rear but if you don’t want yours that low then you can adjust them accordingly) and then jacked up ONLY the spring perch just enough until the spring was taut, no more no less. From what I understand this is the “factory” preload. After that I just adjusted the height of the shock to align the bolt holes and voila.

[@MostGenericUser]

@@Aarejayy I found a good write up on a random forum actually that helped me understand it. One question though what bolts am I trying to line up and with where?

[@Aarejayy]

Aspiring to Inspire 2:23

[@MostGenericUser]

@@Aarejayy oh I've heard on some cars you dont need to remove anything at all just need to adjust it after you mess with the springs

[@x3cerwin]

Im really confused, compression needs 7 - 10mm thats barely half an inch. Can someone explain this to me? He measured the spring, but it was 7cm not mm. Mm is too short. Im probably getting this wrong.

[@TaiMaiShue]

cerwin uy yea the spring just needs to be slightly compressed, not immensely that it shoots out if you unbolt something.

[@RaceStudio]

7 to 10, 5 to 10. just have some compression so the spring doesnt bounce around when it reloads

[@Stock.B58]

On my e92 Bmw my rear springs have extreme play and I can move them freely I know this means I have 0 preload what do I do to preload them?

[@andrewhowells3522]

wind down the collar to tighten up the spring. a good few turns after its stops having free play then lock using the second collar.

[@cyberrr9489]

Hi, Do you have to adjust the shock length again if you were to lower the spring more?

[@Coiloverdepot]

You want to adjust the shock length any time you make changes to the spring adjustment.

[@cyberrr9489]

@@Coiloverdepot thanks for the reply. Oh man what a hassle to do each time then to get a good set height 😓

[@slow_carsgarage7422]

So does a shock or the spring adjust right height?

[@jaylonchung9528]

The spring, the shock is for preload