Coilover/Alignment Question

Hey all, I installed Ohlins coilovers a few months ago and had a track alignment and corner balancing done, ride height was lowered maybe 3/4” or so. Lately I’ve been noticing a bit of a rattle at low speeds from the front suspension when going over small bumps (maybe tie rods?) so I had the car in the air checking everything. In the process I noticed the front springs don’t have any preload while the car is in the air. There’s maybe 3/4” of free play with the spring. Is this normal? This is my first car with coilovers, and the car has been driving fine for the last few months, but this still seems odd. The shop I used was a reputable shop that does tons of race car alignments and such so I’m not ready to just blame them as doing something wrong, but again this seemed a bit odd.

Are you saying when it’s lifted there is no preload and the spring is kinda flopping around? Preload is tension and should have tension even in the air. Most are doing that before you get them… then you adjust the threaded assembly rather than threading the spring…. Did you install them?

Yes exactly, when the car is lifted there is no preload on the front springs. I can move it around myself. I did install them myself and put the recommended pre load on but I’m wondering if the settings were changed when I had the alignment and corner balancing done.

I would thread the spring to get some tension… might have to do both to get them even. It’s happen to me

If I recall correctly Ohlins had called for 2mm of preload (could be totally off as it’s been a number of years since I had one) but it should be included in the instructions that came with the box or you can find it online. Either case springs should not be loose at full droop.

yeah you’re 100% correct, that’s what I set them to when installing. Just wondering how the corner balancing may have affected this. This past weekend was the first time I had the car in the air since the alignment/corner balancing. Shot a message to my alignment shop and will follow up here with their response. No offense to anyone here but I’ll defer to the shop that regularly does work on race cars haha. Was just curious to see if anyone else has this occurrence.

Corner balance should not have an effect as you can adjust the ride height independent of preload. Hopefully alignment place comes back with a satisfactory answer.

Your shop should re due your corner balance as they somehow removed the preload. So when you go over dips and unload the front suspension you go into this 3/4 inch no man's zone of no spring.

To close the loop on this for anyone else who ever wants to reference, I talked to my shop on this as well as another shop I’ve worked with. The consensus was it shouldn’t have slack although it’s not really hurting anything as long as everything is lined up correctly when dropping the car off the lift. Other coilover setups sometimes have the “helper spring” to help keep things lined up while the Ohlins just uses a separate lock ring to adjust ride height.

If you go back to your install spec's, the next time you get your car off the ground so you can see that preload ring setting of two turns. It's probably gone. Other coilover manufactures do not have a preload setting, so that's what you are up against here. You can take your Ohlin install sheet with you and show that guy who wants all the coilovers to be installed the same way. My fronts have just enough preload to spin the spring when in the air. The rear's are rigid no spin. But, that slight amount of slack, I can live with as it does not interfere with the spring travel, as I asked if that preload could be increased to 3 mm. Cantrell said NO. 3/4 of an inch is too much, especially if its different side to side. You can call Ohlin's and have them give your corner balance shop a call. More of a professional courtesy call to set the record straight. Also, if your alignment specialist did this to your preload on one side and not the other, what type of corner balance did you come away with knowing your suspension in a droop situation will have to eat up that 3/4 of an inch before any front spring is compressed. You wonder if your car was the corner balancer's car would he live with that work done. Lastly, you can call Tarett who sells Ohlin's and ask their opinion about the 3/4 preload and see what response you get. ArcFlash is an Ohlin installer, who knows what the preload will do if not set right, can help here. Know, if those were Penske 4 way shocks, they would be setup correctly.

Thanks for the input, very informative. Just to clarify, both front springs were set up this way so I assumed it was related to the corner balancing. That said, if Ohlins mandates the pre-load on their springs I would imagine a proper corner balancing should be able to be achieved by simply adjusting ride height, although I could see where this also might also limit your flexibility when it comes to adjusting ride height. To your point, this seems like a matter of the installer not being familiar with Ohlins and treating them in a similar manner to other coilovers that don’t have a separate ride height adjustment. I’m replacing front tie rods this weekend so I’ll take measurements of everything to see how it stacks up to the Ohlins manual recommendations. I’m curious at this point if the ride height lock ring is positioned the same as it was when I installed everything. I’m guessing it was never changed and all the ride height reduction came from screwing up the preload lock rings.

You paid for corner balancing above and beyond the preload feature of the Ohlins . Others do not have this feature, so your alignment specialist is simply ignoring the 2mm preload ring. My bet is he backed it off to 0. Check with Tarett to get their view of your next steps as a Ohlin dealer.

Called up Tarett and their input was essentially the same as the other alignment shops I spoke with - Yes it’s not ideal to have 3/4” of free space at full droop but really the only concern when driving would be hitting a very large bump and the spring coming unseated and popping back into place. Ohlins is a bit more unique in their design given there isn’t a helper spring. Regardless, I’m having it re balanced and aligned so hopefully the shop will get it correct this time. They should be able to get it balanced using the height adjustment, but just need to make sure it doesn’t go so low that the lower strut hits the lower control arm.

What the issue will be is the billows for the half shaft is almost touching the golden control valve in the rear. I have to use my thumb to turn the valve. You can see the Golden control knob above the half shaft billows. Maybe you should be theire to supervise to assure your 2mm preload is preserved and the ride height balance is 0 when comparing the cross weight from the scales. What you are trying to achieve is the turn in weight transfer is the same from left to right turns. Arcflash LLC - Motorsport Prep, Trackday Prep & Tuning , Please give Josh a note re your issue. He should be able to instruct you on how to proceed so your corner balance is correct. He is listed in the P9 vendor section.

I have Fortune Auto coilovers on two cars and they use a similar system of two lockrings. The spring preload is 1/4 in with this brand. it seems to me like 2 mm is not enough to put any kind of tension on the spring. it should be preloaded after you've reached finger tightness. and then you should use a screwdriver and hammer it a couple times before securing the lock ring. If you forget to do this, then it's extremely easy for the ring to come loose.

Not on a Porsche, but a datapoint... I put the BlackWatch/Penske 550-and-800 setup on my Lotus Elise. Fred Zust, the multi-champion autocrosser, designed this system with Penske. Fred does not believe in helper springs. When set at the recommended 110mm ride height, there was no preload. The springs rattled loose in full droop. This car was driven on autocross courses by several National-trophies friends of mine, including a couple of National Champions. They all were impressed. When letting down the jack after changing tires , there was often a clank as the rear spring seated. This never seemed to present any sort of problem driving on either course or street.

If you don't have any noises while driving you should be ok, BTW, both of my KW-V3'S I have had helper springs..