Questions for those riding on Coilovers

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2008 Mazda5 GT
1) What setup are you running and for how many miles?
2) What are the spring rates front and rear? Anyone go with a custom spring rate?
3) Did you cut-out the access hole for the camber plate (assuming yours comes with one)
4) Most important of all, how do you like them? Would you say it is more race/street/daily driver appropriate? Would you do it again?
EDIT: More questions!
5) Do you hit your bumper stops often?
6) Is load/overloading (weight) a concern?



I'm debating if I should go with coilovers OR go with a good old spring/shock setup. I'm also not sure if it is really necessary to widen the access hole (take a crap shot with a preset). I'm also torn on what rate works best for something that's more of a DD/street friendly. Ideally, I’m looking for it a little stiffer and a little lower. I’d like to be able to carry bikes on a hitch too.

Thoughts/Opinions?
 
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Coil-overs are only DD friendly if you are hardcore into low and willing to make some sacrifices in comfort. I can't speak to the choices available for the 5, but I had COs on my 08 Honda Fit (a nameplate we have in common) There are vastly more choices available for THAT car than there are for the 5, I went with Skunk2 I upgraded to coil-overs from a S&S set-up on the Honda, I loved the ride of the S&S but wanted more low (a word of warning there, low is addictive, VERY addictive) While the coilovers didn't wreck the ride they were FAR from OE. Coilovers, even wound UP all the way will never deliver an OE ride (unless you get custom spring rates, then you're talkin $$$$) Unless you want to go crazy low, or you are headed to the track stick with springs and shocks, my two cents.
 
Disagree. There are SOOOOO many different types of coilovers- you can't lump them into one simple generalization.

Properly matched shocks/springs will ride just as good as stock. So far I have 25k miles (installed 66k, now 91k) on my BC coilovers, and they ride extremely well. Out of the box the damping rates are a little stiff, but they feel good and aren't harsh. Both my wife and I like the go-kart feel, but the grandparents said the kids' heads were shaking too much. Dialed down in softness (I'm at 14/32 front, 12/32 rear, 1 being stiffest) a little, the car actually rides smoother and more controlled than stock. The shocks are able to control the stiffer rates of the springs and even out the harshness that would normally come with springs that hard.

I'm not going to blow smoke up your ass and say that the BCs are super duper awesome and that everyone should get them- to be honest, they're on the extreme low end on the coilover market- but they are a pretty damn good deal for what you get. For the price I paid (well under $1k), I got completely new mounting hardware, new springs, shocks, camber adjusters for the front, and of course adjustable height- all for cheaper than a set of H&R springs and Koni Yellows. Right now I'm set at pretty much the exact same ride height as the H&R Sports, but at a much stiffer spring rate. Without looking them up and based off memory, I think I'm right about 2.5x stiffer in front and about 3x stiffer in the rear compared to stock for the 2009 model year.

So to answer your 1-4 in short without pointing you to my install thread:

1. BC Racing BR Type Coilovers, 25k and going strong
2. Rates = 8kg/mm front (448lb/in), 7kg/mm rear (392lb/in)
3. Yup, cut 'em.
4. Love them, daily appropriate, race capable if you consider the limitations, would do it again for sure given the same budget.

And now more information, and you can call me (I think you have my number in a PM) if you want WAY more information than I'm willing to type out here. I love suspension- got aftermarket suspension on everything. ;)

Just about every single coilover system that you see marketed in the $1k price point is based on a universal damper cartridge. BC, Megan, Yellowspeed- pretty much all of these companies just build brackets around the exact damn same shock cartridge. That's why there are 32 levels of adjustment- the shock has to be able to cope with a WIDE range of applications. You might have maybe 10 useful "clicks" on the adjuster that are good for your car. The rest are there so the shock can adjust to every other car on the market that they can make cheap stamped or cast aluminum brackets for. Don't believe me? Look at the spring rates across the board for a "line" of these coilovers- most will have spring rates that are very similar for the same shock cartridge- makes things easier to match up within the shock's range, or at least that's my guess. Real coilovers that are meant for track duty are completely custom- custom lengths, custom diameters, custom valving etc. If you look at the shocks on my S2000, they're spec'd from the very beginning to work on that car. The length is chosen so that the usable suspension travel is maxed out- you don't lose tons of droop travel like I did with my BCs on the 5. On the street you may not care, but on the track- if you lift a tire, that means you have no grip. My S2k's ASTs won't do that, but the 5 will. It's happened less than a handful of times on the street, but it CAN happen, and if you've just overcooked a corner, lifting a tire is NOT something you want to happen. Why does the droop suffer? That universal cartridge has to be pretty short to fit into all those brackets that adapt it to all those different cars- so the maximum extended length of the shock is pretty short. You have a much shorter cartridge giving you shorter stroke within the space of your stock shock, so your range of motion is reduced. To maintain anything near a stock ride height, you have to give up something- the wheel can't drop when it needs to. If you go super low like a lot of people do with the cheaper coilovers (stance y0, screw performance!), then you regain some of the droop since you're riding around compressed, but you lose on the compression end. Just one of the many disadvantages to think about.

That shorter shock cartridge also means less fluid to do the work of converting motion to heat, which means that it can overheat faster. Again, not a problem for most on the street, but take it to the track and beat on it for a long time, and you could cook the fluid. Overheat = loss of viscosity or loss of uniformity = no control. Quality coilovers have larger bodies to allow more fluid, monotube to allow more fluid and bigger pistons, and external reservoirs to hold more fluid... see a trend here? The stock rear shocks in my S2k have external reservoirs. Huge off-road suspension setups? External reservoirs too. That should tell you something. Does the 5 need anything like that? Nah, but again, something like the BCs typically has LESS fluid than stock. They make it work pretty well, but again- another typical drawback on the cheaper universal coilovers.

Ride quality- a lot of people adjust their universal coilovers incorrectly and end up topping out or bottoming out the shock cartridge during the stroke- that's why the companies tell you not to play with the spring pre-load, and to only adjust the physical length of the outer threaded section of the coilover body. That keeps the operating range of the coilover in its sweet spot. If you change the pre-load on the spring, you're changing the stroke range position on the shock- and you can run into the physical limitations of the shock itself, which already has a shorter stroke to begin with. The manufacturers counter some of this problem with the higher spring rates- more rate = more reduction in travel = less chance of hitting the hard stops at the end of the shock. Stiffer springs do not always mean better handling on a car, but most of the aftermarket community doesn't understand that.

There's a LOT more I could type, but I think you get the idea... some of the "universal" coilovers work pretty well if you understand their limitations. I love mine, but I wouldn't run them on my S2000. It's on coilovers too, but at a completely different level. My 5's ride is still very nice, and can be dialed in super tight if I want it to be- and given the limitations listed above, I can still drive the hell out of it and not worry one bit. It's not going to spend (much) time on a road course, and never competitively. Well, maybe never. The stiffer rear rates have been kinder on the rear tires since there's less toe change under load, and the rear doesn't squat anywhere near as much with the car fully loaded, including the roof box. I lose maybe half my sidewall, and I have barely an even gap all the way around the tire with the car unloaded. I still have room to raise the car, probably up to stock height if I wanted to- but I won't. The camber plate hole isn't necessary, but you're not going to get the settings right by guessing, and you'll kick yourself later for not cutting it out. It's not THAT hard. You could get camber bolts for the strut upright too, but won't be able to adjust as much.

Hope that helps- need more, call me. :)
 
Thanks phunky for the feedback! I may reach out to you with further questions. Actually, I already have a question -do you have any experience with Swift or Hypercoil springs? Do you know of a good source/link for aftermarket coilovers springs? Ok, that was two questions :)

I completely agree with what you saying regarding coilovers. To lump a bad set with all CO is a bit of a gross generalization. Also Skunk2 is NOT a good example. I always see them used for the purpose of slamming with little consideration for comfort (former Civic owner). It boils down to springs and dampers. You can argue one setup gives more flexibility than the other but the practical sense does not change, both can be good or bad. What I'm hoping to find/hear is what kits springs are generally available with their setup and how well they ride considering this is genearlly used as a family car, props to those who use it otherwise. I also understand the feedback I'm going to receive will be 100% subjective b/c we all have different butt dynos :p

Confession time. I have Yellowspeeds in the garage since winter. It typically takes me ~2 years before I do any mod but with summer nearing end, I feel I should do "something" with them: install or sell. If installing, I "want" to do them right but the money pit scares me and play time is short so I would need to plan accordingly. I still have not taken measurements but the marking indicate 2.5" diameter, 8K springs front and ~3" diameter, 8K springs rear; both very common. The US Mazda 5 automatic weights in at 3475 lbs and has a 57% Front (~1980 lbs) and 43% Rear (~1494 lbs) weight distribution (Source: Motor Trend). I have concerns the rear @ 8K might be too stiff. Granted my previous experience says a stiffer rear = more planted (not stiff) ride. Still, I have concerns as every car is different. In general, I'm more concerned both F&R springs at 8K are on the stiffer side of my needs. I'm contemplating if it is worth $$ swapping them out for 6K front and 5K rear. I believe the general rule is +/- 2kg/mm is ok so the 5K rear is a bit of a steep change. Thoughts??





The dyno is from a Toyota (not sure what model) DSP line so I would think it is close enough. I don't take it as absolute but it seems to be missing the low end curve on the compression side for low speed comfort but I don't take this chart as absolute or to reflect reality.


Oh, and regarding cutting the shock mount, this is purely superficial and looking to save some cost and time if it is not absolutely necessary. The DSP camber plate comes in a 'square' instead of round like the BCs. While widening the hole will allow access to the camber bolts for finer adjustments, which is great, I think it might look a little goofy...

I also lower all of my cars but have always stuck with S&S due to simplicity, cost, and consider the salt damage to the suspension. This is my first foray into full coilover setup so I am very tempted. IF there was a less aggressive drop spring for the Mz5 on the market, I would prob still prefer it paired with MS3 Bilsteins. Unfortunately this is not an option so I feel like I have little choice. I've never been nor do I want to *slam* it, esp not on this car given the DD action it goes through. Actually, I like tire more than rim, if that makes sense. Both the missus and I like a stiffer ride too! We just have to be mindful of kids, passengers, and other stuff –stuffed in the car.

I also asked this in the Miata world a while back. The most logical response I got was from Keith Tanner (Flyin' Miata) who said to just try it out first, then change springs as necessary but I don't have that kind of time. The other suggestion was to go to a local race shop and try their springs before buying. Sound great but not a realistic option either nor did I know this was an option.


A few more questions for Mz5 coilover owners
-Do you hit your bumper stops often?
-Is load/overloading (weight) a concern?
 
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Hokay.

8k isn't too stiff. 7k feels pretty damn good on my 5. The Yellowspeeds look like they're set up well enough to probably control a spring rate like that. The shock dyno looks halfway decent- preset compression that stays pretty constant, so it looks like you have adjustable rebound with pretty level compression damping and not much cross-talk between the two. For comparison, here are my ASTs (click for big):



Notice that the line shape is similar to your Yellowspeeds, but look at how the pairs of shocks match up against each other- that's important. The linear response is a lot more predictable after you cross over the "knee" going from low speed to high speed response- low speed giving you more control in turns, high speed giving you less rebound damping and more comfort/control over the sharp impacts. I can be leaned over pushing 1G+ in a turn and hit some irregularities in the road and not have the car upset at all. This graph is only part of the story though- you can't get a real idea of how a shock will perform just from this one dyno plot, although it seems to be the most common plot shared (if ever) about shock performance.

Here's a good thread showing the BC coilovers and discussing more about shock behavior with even more plots- plus some evidence that the BCs aren't super matched out of the box. Your Yellowspeed plot probably holds true for all their shocks using a universal cartridge. :D

http://forums.nasioc.com/forums/showthread.php?t=1227124

Why not pair the H&R springs with the Bilsteins? It's a good setup- and I'm riding at the exact same height that the H&Rs would give you- just with higher spring rates. You don't have to screw with getting the ride height juuuuuuuuust right (took me several rounds of adjusting, setting car back down, letting springs settle, measuring, then repeating the whole lifting and adjustment process again and again and again) to where I was happy. I wouldn't consider the H&Rs very aggressive compared to your Yellowspeeds, but I guess you've already bought them. Mine's far from slammed- even gap all around.

More tire than rim, totally understand. I like a good balance, but I like cheaper tires more. No 18s for me. I have 17s on all the cars except the CRX- tires are way cheaper than way. :D

Hit bump stops often? Nope. I've hit them stock though during "emergency" maneuvers.
Overloading, nope. I have more spring and more damping, so don't lose any capacity, even with the lower ride height.

Swift and Hyperco? Yes and yes. Good experiences with both. I have Hypercoils on my S2000 right now with the AST shocks.

As for your spring rates, leave them alone on the Yellowspeeds. You'll be fine. I'm sure the shocks will match up similar to how my BCs do on my 5.

I would also seriously consider cutting the shock tower. Since you have a square cutout, just drill 4 holes and cut between them with a jigsaw. :D
 
I am humbled and educated damn near every time I get on this forum. Good points made and good info! Where did you get the Yellowspeeds from? I realized pretty early on with the COs on my Honda that I didn't really know enough to get them set up 100% correctly, so I got them as close as I could to where it would align properly and not eat tires and called it a day. In retrospect there was a lot I should and could have done better/differently, but I learn best by screwing up LOL I want H&Rs and Konis very much for the 5, I think it will give me the results I seek....
 
Don't worry, most people, especially 5 drivers- really aren't going to go to these lengths on suspension setup. I tweak sway bar setup, set corner weights and ride heights as exactly as I can because I don't have to pay someone else hourly to do it, etc... There's not necessarily an advantage to running adjustable coilovers and shocks vs lowering springs with a preset fixed height- the "cheapo" coilovers are usually adjustable like crazy because they're built with as many common parts as possible- so you HAVE to have adjustable damping and height just to make the same parts work on every car. If you have a spring/shock set that's already going to work well, go with it.
 
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