Installed my BCs yesterday. Hmmmm

[feeshta]

So yesterday I finally got time to install my BC Racing coil-overs. Sorry no pics yet, the car is still filthy from doing the job. The install was not too bad. the front was easy and I had both front shocks the brake rotors swapped out in just over an hour. The rear was a bit more of a pain though, as getting the fender liners out was a very dirty job. It seems that every dust particle from the last 13 years was waiting for me in that fender liner, and blasted me right in the face when I pulled it loose :shifty Also, re-installing the driver's side rear fender liner was an absolute nightmare. I think it must have warped from the heat of the exhaust or something, but it absolutely will not go back as it was before I took it out. the passenger side onf was pretty easy, but the driver's side simply will not cooperate. For one thing every single one of the metal screws that held things together snapped like twiggs, and the screw clips they bite into are nothing more than a smudge of rusty dust. I'm going to have to get new hardware for that it seems. Even one of the posts that the 2 plastic nuts screw down onto snapped off. Eventually I got it into a manageable position for now, but it's not right and will probably need replaced. Anyone else run into this issue? If so how did you go about correcting it.

I was not able to install my alignment kit yesterday, as I ran out of time due to the fender liner issue, so I will have to do that next week. I might have had time, but was unsure how long it would take to press out the old bushings and install the new, and I needed the car in one piece for the ride home. The car seems to be tracking ok for now, and the tires that are on it at the moment are on their last legs anyway so I am not worrried about them.

Now, on to the ride. I have not had enough driving time to monkey with them much yet, but initial perception is that it's quite a bit too too stiff. I didn't go very low, .75 in lower in front, .5 in the rear, and I have them set at 15 clicks right now, but the ride is more than a little "jiggly". I turned them all the way up last night just out of curiousity, and the result was comically stiff. The car handled amazingly, but on Baltimore roads it felt like a tank with broken shocks. I nearly hit my head on the ceiling, no kidding. I need to get the ride tamed a little bit from where it is now, the jigglyness is annoying, and I know it will piss me off over time. Right now the ride is roughly equivelent to my cousin's 2006 WRX STi, which is one of the harshest factory suspended cars I have ever ridden in or driven. Any suggestions on where I should go with the settings?


The other issue is that rather than help cure the vibration issue my car has, it seems it simply became a lot better at transmitting it into the interior. That's not BC's fault my any means, but it does detract from the whole experience. The vibration feels almost like that feeling of vibration you get when you have a shopping cart with a bum wheel. It varies in intensity, and is a thrumming sound that has the feel of coming from an unwanted source of friction rather than from something out of balance if you know what I mean. I did also replace the front brake discs yesterday as well, as they were below speck on thickness, and thought that might help, but it apparantly did not.

So, any suggestions guys?

[apocalypsegoat]

.

[feeshta]

I guess I missed what was said there. Any particular reason for posting nothing but a period?

[528canyonrot]

I feel you on the rear fender liners being ridiculously dusty behind there lol. It was a pain for me as well. I think you just need to get a lot of drive time with the suspension to really get it to loosen up, it will take some time and you will notice the difference. Then you can adjust it from there. But that's my opinion.

[feeshta]

I was wondering if that might be the case to some degree myself. I do need to spend a little time dialing in the settings as well, but I guess that is somewhat pointless if the suspension will loosen up considerably.

The vibration issue is really driving me nuts though. I need to get that solved.

[FlipredE36]

Did you do this yourself or have a shop do it?

[feeshta]

I did it myself. Quite honestly it would be really easy if you did not need to remove those damned fender liners. The most difficult part would probably be taking out the rear deck to get to the top of the rear shocks.

[FlipredE36]

I'm trying to do mine as well. Did you need any special tools? The Beisan site says to remove the outer tie rod but some say it's not necessary. Not sure if there are any differences between the I6 & V8.

[rf900rkw]

Yes, there is a big difference between the V8 and I6 front suspensions. I believe the I6 requires cutting loose the tierod, the V8 does not.


On the suspension, I doubt it will loosen up that much. What is there to loosen? If things need to wear in that much, I would have serious doubts about the durability of the components.

[FlipredE36]

Yes, there is a big difference between the V8 and I6 front suspensions. I believe the I6 requires cutting loose the tierod, the V8 does not.
Looks like I'll need a ball joint tool.

[Justin517]

It is stiff, but you don't buy a coilover suspension setup with over 100 lbs/in. stiffer than stock springs and not expect that... also I'm at 15 clicks right now and it is quite stiff but I like it for the spirited driving I tend to do, everyone's ride smoothness requirements differ, what is just right for me may be too harsh for a wimp... I mean you... just kidding!

dial it back to 10 and slowly increase until it is uncomfortable and then go back a click.

I didn't have any issues with the rear liners, but my car also has the M5 liner setup which seems to have less lip to it. The scariest part for me was pulling out all that evap. system stuff, but it all went together with no problem and there were no BS codes for it after, lol.

Did you get it aligned yet? If not you are probably toe'd out a bit. As far as the vibration, you will feel more road imperfections, I don;t mind it except for one spot on the highway where traffic always builds so it has had years and years of people stopping, the road is rippled, the car bounces/wiggles up and down... its almost kind of comical.

[feeshta]

It is stiff, but you don't buy a coilover suspension setup with over 100 lbs/in. stiffer than stock springs and not expect that... also I'm at 15 clicks right now and it is quite stiff but I like it for the spirited driving I tend to do, everyone's ride smoothness requirements differ, what is just right for me may be too harsh for a wimp... I mean you... just kidding!

dial it back to 10 and slowly increase until it is uncomfortable and then go back a click.

I didn't have any issues with the rear liners, but my car also has the M5 liner setup which seems to have less lip to it. The scariest part for me was pulling out all that evap. system stuff, but it all went together with no problem and there were no BS codes for it after, lol.

Did you get it aligned yet? If not you are probably toe'd out a bit. As far as the vibration, you will feel more road imperfections, I don;t mind it except for one spot on the highway where traffic always builds so it has had years and years of people stopping, the road is rippled, the car bounces/wiggles up and down... its almost kind of comical.

Evap stuff? Not sure what you mean there. The only thing I had to move other than the liners was the gas filler neck and the cabin air filters. Other than the interior of course. Part of the problem with the liners was that a previous owner rolled the fenders, and it made getting them in and out a bit tough. If I do it again I might want to trim them.

I expected a stiffer ride, and honestly was a little worried it would be too much, but went with the recommended rates after a lot of deliberation. The springs are actually roughly twice as stiff as factory springs, which is a pretty big difference and you certainly feel it. Right now I don't think it's going to pass the GF test, although the results would be rather entertaining to watch :D It just seems like it might be just a bit too stiff for my normal driving cycle. It's great when you get out on a back road, but unfortunately 95% of my driving is city or highway driving. It's really not the stiffness that I mind so much as a tendency towards being jiggly, not sure how to best describe that, but it seems like it soaks up the big stuff much better than the small stuff.

The Vibration issue is something other than the suspension. It's coming from something that spins, but I'm about at wits end on finding it. The change in suspension simply made it more palpable due to the fact that the increased stiffness transfers it more strongly to the driver.

Randy: I don't think there is anything that loosens so much as the components get worn into each other, like an engine wearing in to some degree. I know my old GTI 337 definitely smoothed out a bit after about 2 weeks of driving, and a previous Golf VR6 did the same when I replaced the factory shocks with Sachs adjustables over in Germany.

On the install, 8 cylinder cars just need to pop one side of the swaybar loose and then either have a jack handy to support the assembly or disconnect the brake calipers to keep it from hanging on the brake line. 6 cylinder models I really can't comment on. You will need a second guy to do the rears, simply because you can't be both inside and outside the car at the same time, unless you have REALLY long arms. :D

[feeshta]

Well, I dropped it down to 10 clicks today and went for a drive. It's actually much better at that setting. It's still quite sporting, but not so punishing like it was before. I'm going to have to track down a few rattles that are worse now and driving me a little batty, but the ride is much more reasonable and I am much happier with it.

[VFTS]

For vibration, check your rear rotors.

[keith2]

I dont see why everyone removes the liners and evap stuff? I did it with no issues without removing. Also my car is an i6 and to do the fronts it isnt ABSOLUTELY necessary to remove tie rods either. Just undo top nuts, the clamping bolt on the hub, and let it drop down. I compressed the shock/spring a little to clear the fender as you let it all drop out, and out she came. Had both fronts done in about 20min. The hardest part for the rears is getting the rear parcel shelf outta the way, irritated me the entire time lol

[RVAE34]

If it doesn't pass the girlfriend test, get a new one :) The gf, not the car..

[Justin517]

I dont see why everyone removes the liners and evap stuff? I did it with no issues without removing. Also my car is an i6 and to do the fronts it isnt ABSOLUTELY necessary to remove tie rods either. Just undo top nuts, the clamping bolt on the hub, and let it drop down. I compressed the shock/spring a little to clear the fender as you let it all drop out, and out she came. Had both fronts done in about 20min. The hardest part for the rears is getting the rear parcel shelf outta the way, irritated me the entire time lol

Liner removal makes it much much easier to remove the strut without over-extending the lower control arm, you can squeeze them out by reefing on it but the rubber bushings may not like it much.

[rf900rkw]

Well, I dropped it down to 10 clicks today and went for a drive. It's actually much better at that setting. It's still quite sporting, but not so punishing like it was before. I'm going to have to track down a few rattles that are worse now and driving me a little batty, but the ride is much more reasonable and I am much happier with it.


One thing I have not been able to find anywhere.... what does the adjustment on the BCs do, exactly?

[James39]

How's your transmission and engine mounts?

[feeshta]

For vibration, check your rear rotors.

Replaced less than 2 months ago.

- - - Updated - - -


If it doesn't pass the girlfriend test, get a new one :) The gf, not the car..

You see my avatar right? She's not going anywhere. :D

- - - Updated - - -


How's your transmission and engine mounts?

Replaced about a year ago.

I went for another drive tonight. Set at 10 from full soft, it's near ideal and I am very happy with it. I just need to invest in a little sound deadener I think and hunt down a few rattles. Especially one in the rear deck that makes a loud slap noise over seam type bumps. There is also a little bit of clunking coming from the front, but I think that is the sway bar bushings. There is a lot of play in the front bushings because the bar rusted inside the bushing and tore it up. I need to replace the whole thing, but have been putting it off because it looks like a shitty job. I'm actually considering just cutting the old one in half and taking it off to see what happens.

[feeshta]

OK, so I went on a trip to Boston this past weekend, from Baltimore. I think my spine will need a couple weeks to decompress, and the interior of my car is definitely rattling more after the trip that it was before. Granted the roads in NJ, and Connecticut are horrifically bad, but I am realizing that this setup is simply too stiff. It's going to turn my car into a rattle-trap, which I despise with a passion that cannot be explained in words. I hate when shit rattles in my car, it's the biggest pet peeve I have in life. I'm a more dangerous driver with a squeak in my interior than I am with a cellphone in my hand, because I become obsessed with finding and stopping the aberrant noise.

I think I'm going to have to change the springs out for lower rates when I have time. Oddly, the rears seem worse that the fronts. The front tires absorb sharp bumps with a tolerable thunk, then rears give a loud THWACK! noise that reverberates through the interior.

[Jason5driver]

What tires are you running...?
Tires will affect the ride of your car dramatically, especially if your car is on coil-overs...
Ask me how I know...
:D

[Justin517]

Are you sure the shock rod nut where it bots to the mount is tight? How about the mount to the body? I drive from central ct to the MA line every day and my car is stiff but it doesn't rattle or make any "thwack" noises.

People have complained about knocking from the rear, it was usually a loose rod nut.

[geargrinder]

Oddly, the rears seem worse that the fronts.

Not entirely surprising - performance spring setups usually really beef up the rear rates to reduce squat and plant the rear more firmly. I'm with Justin though - go through everything and be sure its all "correct" before redoing the springs...

[topaz540i]

I never removed my fender liners. Just rent a spring compressor for $30 and shorten the spring while its on the car and they come right out. Installing the new shock i just screwed it down to the lowest ride height setting and it slid right in.

[Justin517]

Messing with compressors on the stock spring/damper then completely shortening the coilover then re-extending once installed likely takes just as long or longer than removing a few expanding rivets and pulling the liner.

Also, if you stick a block of wood between the lower control arm and the unibody/subframe (I forget which) before pulling the damper/spring it's pretty easy to remove the whole assembly and the coilover slips in even easier.

[feeshta]

Everything is tight, I think it's the rear deck that makes the offending sound. I am having a vibration from the rear end that might be somehow related to the harshness, but for the life of me I can't find the offending issue. You can read about that ongoing saga in my mystery vibration issue thread. It's not really a knocking sound. I'm not sure how to properly describe it if honest. It sounds more like the entire rear deck is slapping against the metal undeneath when I hit a harsh bump.

The tires are nearly new Conti DWS on the factory 17 inch style 32s.

I'm also getting a little bit of noise from the front suspension when turning tightly at low speeds, a popping type noise. I went through and checked that everything was tight the other day when I changed the oil. Was able to tighted the bolts through the center of the thrust arm bushings a little bit, and that made a difference to the positive, but there is still noise there. I guess they worked loose over time. The noise might just be something you have to live with though.

[Justin517]

your rear sway bar brackets aren't broken, are they? I had an annoying clunk now and then and it was a broken sway mount bracket whacking against its mount point.

[feeshta]

your rear sway bar brackets aren't broken, are they? I had an annoying clunk now and then and it was a broken sway mount bracket whacking against its mount point.

No, I checked them just before I went on the trip, along with the rear subframe bushings, diff bushings, and everything in the front suspension. Had it on the lift to change the oil so I took the opportunity to poke around.

[joel540i]

What spring rates did you go with and do you have an i6 or v8?

The snap sound could be a shock mount?

[feeshta]

What spring rates did you go with and do you have an i6 or v8?

The snap sound could be a shock mount?

After a lot of deliberation over the spring rates, I went with the board recommended 8K front, 6K rear setup for a V8 car, which mine is. As near as we could figure, the stock sport suspension spring rates are somewhere near 3.5 K front, and 3K rear, so I was a little hesitant to make such a drastic increase in spring rates. It seems my hesitance may have been well founded, but I really do need to find this damn rear end issue before I make a final decision. The nice thing is that you can get new springs from Swift Racing for about $250 to change the rates. The pain in the ass is actually replacing them.

The shock mounts are replaced with the BC setup, so the only issue there would be if they were loose.

[topaz540i]

Did you recheck your preload? The springs may have settled/shortened a tad. Just an 1/8th would be enough to make them loose. The difference between ride height and full droop should be no less than 1.6 inches and no more than 1.96 inches if i remember my calculations correctly. Out of the box the springs have zero preload.


Im also getting a noise from my rear deck that i didnt used to have. I think its rattling where it tucks up against the rear windscreen. Maybe next time i wake up with a new pair of panties on the mirror i can jam them into the back window to make it stop.

[Graham E39 528i]

These are my favorite threads. The ones that start with an interesting story.

Thanks Feeshta et al.

Sent from my Nexus 7 using BF.com

[feeshta]

Did you recheck your preload? The springs may have settled/shortened a tad. Just an 1/8th would be enough to make them loose. The difference between ride height and full droop should be no less than 1.6 inches and no more than 1.96 inches if i remember my calculations correctly. Out of the box the springs have zero preload.


Im also getting a noise from my rear deck that i didnt used to have. I think its rattling where it tucks up against the rear windscreen. Maybe next time i wake up with a new pair of panties on the mirror i can jam them into the back window to make it stop.

I didn't actually check the preload, I just checked that everything was still tight. Mine actually came with the preload set, but I went through and reset them just to be safe when I installed them. Will recheck preload the next time I have it on the lift.

- - - Updated - - -


These are my favorite threads. The ones that start with an interesting story.

Thanks Feeshta et al.

Sent from my Nexus 7 using BF.com

Happy to be of service Sir. :)

[Justin517]

I still think you should check the upper shock rod nut. Unless you removed the rebound adjuster and put an impact on it, there is no way to be sure it isn't loose.

Do you have rear extenders installed? if so did you route them out of the deck or are they just tucked under the grill or something?

[DHoang]

After a lot of deliberation over the spring rates, I went with the board recommended 8K front, 6K rear setup for a V8 car, which mine is. As near as we could figure, the stock sport suspension spring rates are somewhere near 3.5 K front, and 3K rear, so I was a little hesitant to make such a drastic increase in spring rates. It seems my hesitance may have been well founded, but I really do need to find this damn rear end issue before I make a final decision.


Basically, your spring rate is way too stiff for the weight of the vehicle. Plus, b/c you feel jolts in the rr more so than the front (if any), sounds there are some binding problems that may be going on in the back. It'd be better if you feel these harsh jolts concurrently, but b/c it's more localized in the rr than front, then there's an imbalance occurring as the suspension strokes up/down.

You need to account for the fact that a stiffer spring will coil bind at a much shorter travel than softer springs b/c of the larger diameter coil of wire that's used for stiffening up the spring rate. This increase in wire diameter takes up more space between the two spring perches, leaving less gap between each coil winding, so now those stiffer springs installed in the back is coil binding up at some point early in the suspension travel, before the bump stops make contact w/ the top plate.

A common mistake most people make is in thinking that the way to change how a car rides and handles is to alter spring rates. Springs are only position sensitive. THey are not speed sensitive. As such, the spring's main role should be to just POSITION the vehicle and occupants at a set ride height. To that end, There is only ONE CORRECT spring rate for positioning your car at a particular set height based on the car's weight and occupants. But!!!!!! because it's economically not feasible to make thousands of different spring rates for you to select, we have this neat invention called a coilover, and through this mechanism called the preload adjustment rings, we can change the amount of spring rate (via preloading) for the position we wish our car to sag at. Each millimeter that the spring is compressed, the spring rate increases by, in your case, 6k units. So this unit of measurement is based entirely on where, or the position of, the spring is under preload vs. @ zero load. IT could care less how fast or slow the suspension is going up and down...all it is able to do to increase/decrease the force applied per a given displacement in position.

WHen the car is in motion, the way the car behaves and how you control its suspension movements is by changing the damping rate, not by changing spring rates. So, there's this invention called a stack of shims that is designed inside a damper to control how quickly or slowly we want the suspension to move up/down. This is the best & most direct method because it directly controls the speed sensitivity part of suspension movements. But don't confuse changes in valving w/ the external adjusters that are provided on the BC & other high end dampers. These external clickers only change one small portion of the damping curve, mainly the low speed function, not the high speed function, which is what's causing all those rattles you're complaining about. YOu can click all you want, but that is only going to change 10-15% the speed sensitivity, and again, that portion is only for the low speed circuits, not the high speeds, which is mainly what we use mostly when we ride on crappy streets.

So there's not just spring rates for u to address, but also valving....valving to match the high and low speeds of your particular riding style, plus valving to match the spring's rate....It's all a matched set, when you change one, you change the other, whether or not you like it.

[BioGuy]

The only thing I took away from this thread is that I need to see more pics of Feeshta's girlfriend.

[DHoang]

The only thing I took away from this thread is that I need to see more pics of Feeshta's girlfriend.
LOL
http://cdn.lolzbook.com/wp-content/uploads/2012/11/Gtfo-Btch.jpg

[Justin517]

freeshta said he set the pre-load before installing, it sounds like it was possible that preload was set too high?

When I set mine I simply loosened the collars until the spring was loose, then spun both collars together until the upper one JUST made contact with the spring, held the locking ring in place and continued tightening the upper ring (the perch) until I was able to slip the wrench between the collars (5-6mm), then you hold the upper ring/perch in place and tighten the lower locking ring.

If you went more than 5-6mm or didn't securely hold the perch when tightening the locking ring, you quite possibly have too much pre-load.

[rf900rkw]

Preload is one of the many misunderstood things. It has nothing to do with the stiffness of the spring. Nothing. Zero. All it does is set the loaded ride position relative to the shock travel.

Example out of the air:

1:1 suspension ratio, 800 sprung weight, 400 lb/in spring rate. 4 inch of shack travel


With the preload set to zero, just zero load on the spring when fully extended. When the car is placed on the ground, the spring will be carrying 800 pounds at a rateof 400 lb/in. The shock will be compressed 2 inches, with only 2 inches of bump travel left.

Preload the spring 400 pounds (wind the seat up one inch). Once the car is dropped on the ground, the weight carried by the spring will be 800 pounds. The spring rate, 400 lb/in. But now the shock will only compress one inch, leaving three inches of bump travel.The first 400 pounds placed on the spring is used up with the preload; transfering the load from th shock top limit to the car without any actual compression.

I'll let you guys do the math for a preload of 600 pouinds.

Spring rate is not changed. weight is not changed. only the shock position is changed. This is the whole idea behind these newer shocks, allowing you to set the shock travel position independently of the ride height position.


The problem Feeshta is experiencing was predicted before he bought the shock set. The suspension frequencies are, well not off the scale, but way too high for a daily street car. The fact that the rear seems to be worse is probably down to a mismatch of front and rear frequencies.

[topaz540i]

Isnt half the point of setting proper "sag" that you need wheel travel in both direction of the static load position? Set the preload too high and you have no sag left and end up with wheel lift when the road dips.

[joel540i]

So I was about to buy BC's for my 540i. Everything I ever read was go with 6/8 rates. Now I'm second guessing if that really is the best for a daily driver.

I wonder if swift springs really make much of a difference... And what rates they offer.

[Justin517]

Randy, so coil bind can't come into play with excessive preload?

[rf900rkw]

Coil bind will only happen if you put more load on the spring than it is designed to handle. If you coil bind the spring, *someone* somewhere didn't do their engineering. Let's go back to the same example maths. Say the spring binds up at 4 inches of travel, still 400 lb/in. (sorry, I'm old school). That means that 1600 of force is needed to bind up the spring. If you have zero preload, it will take 4 inches of travel to create that 1600 pounds. If you jack the spring seat up three inches, the first 1200 pounds of force will be used up taking the load off the shock top bump, and the final 400 pounds will compress the spring one inch before binding. It still takes 1600 pounds to cause the bind.

[newton22]

freeshta said he set the pre-load before installing, it sounds like it was possible that preload was set too high?

When I set mine I simply loosened the collars until the spring was loose, then spun both collars together until the upper one JUST made contact with the spring, held the locking ring in place and continued tightening the upper ring (the perch) until I was able to slip the wrench between the collars (5-6mm), then you hold the upper ring/perch in place and tighten the lower locking ring.

If you went more than 5-6mm or didn't securely hold the perch when tightening the locking ring, you quite possibly have too much pre-load.

Hmm I set the preload before I installed mine and I tightened the collar fairly tight by hand and then spun an additional 4mm (or however thick one spanner wrench is).

Funny how all the young guys here want their cars extra stiff. I'm running 8k/6k 17 clicks from soft F/15 clicks from soft R on my I6 and I still think it's soft.

[topaz540i]

How can u guys accurately set the preload with the suspension off the car? Did you check for proper sag? The window is less than half an inch according the instructions.

[feeshta]

Update: So, I've been pretty busy the past couple months, and I moved to an apartment that is a lot closer to work which lengthens my oil change interval. This past weekend I changed the oil and decided to check the coil-overs again. The springs have definitely sagged, as the preload was no longer correct and the measured ride height had dropped by about 1/8th to 1/4th inch all around. I reset the preload on all 4 corners. Three of them had become loose enough to spin by hand once you released the locking ring. This has almost completely eliminated the popping noises. The ride is still quite stiff, but as long as I avoid New Jersey it is not too much of a problem for the time being. The interior noises mostly seem to have calmed down, which is slightly odd. I'm not complaining though.

There is still a slight bit of thunking in the suspension though. My thinking is that it might be the sway bar bushings, which I know are bad. I've been putting off replacing the sway bars because I know it's a bear of a job on the V8 cars in the front, and my front bar needs entirely replaced due to rust inside the bushing area. Anyone have any insight into what effect worn sway bar bushings would have?

[mifesto]

BC coilovers have a minor but known issue of the locking rings coming loose which is what probably happened. also preload collars should not compress it enough to change the spring length, if you did you had TOO much preload. http://www.youtube.com/watch?v=HlqOA35NmAw also your clunking noise as you said may be coming from your suspension bushings. that's understandable since elimination of the rubber top mount will significantly increase noise transmission from suspension to your cabin.

[Johntee540]

[QUOTE=feeshta;26752223] The ride is still quite stiff, but as long as I avoid New Jersey it is not too much of a problem for the time being. QUOTE] I think avoiding New Jersey is a good best practice to begin with! Be Good - JT

[feeshta]

I generally avoid Jersey, but when you are driving from Aberdeen MD to Boston and back, it's a bit of a detour to go around :))

When I got the BCs, I set the preload according to their video and checked all of the hardware for tightness. None of the locking rings were actually loose, it was just that the springs were loose against the perch rings because they had compressed a bit. It's pretty obvious that the springs compressed slightly after a couple months of use.

The thunking I have now is more felt that heard. I doubt passengers would notice it, but you do as the driver. It's not really present on one-time bumps like a bridge transition of something like that. On those types of impacts I get a pleasant solid sound and feel. When the road surface becomes bumpy, and especially when it is wash-boarded, is when I have an issue at this point. All of the bushings in the suspension have been replaced with the exception of the rear subframe bushings and sway bar bushings.

[Justin517]

you only replaced the front control arm bushings, not the whole arm?

[feeshta]

you only replaced the front control arm bushings, not the whole arm?

No, I replaced all control arms front and rear. Fronts have Meyle thrust arm bushings, everything else is new Lemforder. with less than 15K on them at this point. Rear ball joints, sway bar end links, integral links, etc were all done as well.

[Jason5driver]

Coil bind will only happen if you put more load on the spring than it is designed to handle. If you coil bind the spring, *someone* somewhere didn't do their engineering. Let's go back to the same example maths. Say the spring binds up at 4 inches of travel, still 400 lb/in. (sorry, I'm old school). That means that 1600 of force is needed to bind up the spring. If you have zero preload, it will take 4 inches of travel to create that 1600 pounds. If you jack the spring seat up three inches, the first 1200 pounds of force will be used up taking the load off the shock top bump, and the final 400 pounds will compress the spring one inch before binding. It still takes 1600 pounds to cause the bind.



Coil bind will only happen if you put more load on the spring than it is designed to handle. If you coil bind the spring, *someone* somewhere didn't do their engineering. Let's go back to the same example maths. Say the spring binds up at 4 inches of travel, still 400 lb/in. (sorry, I'm old school). That means that 1600 of force is needed to bind up the spring. If you have zero preload, it will take 4 inches of travel to create that 1600 pounds. If you jack the spring seat up three inches, the first 1200 pounds of force will be used up taking the load off the shock top bump, and the final 400 pounds will compress the spring one inch before binding. It still takes 1600 pounds to cause the bind.

Interesting....
I have been getting coil bind with my H&R coil-overs, and H&R said that it is normal...
The springs are progressive.