Ksport coils: delivering plenty of dissapointment

[deth2u]

I bought a set of Ksports from JNZ a year ago, and the car has moved a few hundred miles since then. The DSM is really an off-and-on project for now. However, I really should've inspected these before installing them.

Last night I had a good buddy of mine, Dean from Honsport, dropped by my shop. He's a pretty hardcore suspension tuner and tweaker. He's raced in NASA pro Honda challenge for a few seasons.

I had my suspension disassmbled and the engine out while doing some finishing work on the targa top, and some chassis stich welding / prep work for the roll cage. He happens to see my coils on the shelf. That's when my night got a little sour.

He said those things aren't all that great, the spring rates are questionable and they have no suspension travel. So we decide to check them out. I disassembled one and removed the spring.

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Yup, you see it here. A whole two inches of suspension travel, free length to bump stop, and 16 adjustments of practically the same damn damping. We were adjusting soft to hard, checking rebound and compression, and it all felt the same--from full soft to full hard.

I do a lot of canyon racing when the car isn't being serviced, exploding driveline parts, or towed back to the shop. Obviously two inches of travel is dangerous and will easily bottom out, bump steer, or whatnot. So, as a band-aid for now, I dug around and found a few sets of 2.5" ID Hypercoils / Eibach ERS I had back from the day. We installed 800 in/lb springs in the front, and moved the 12kg/mm fronts to the back, since all I had left were 900s and 1000s.

Will buy another coil-over suspension, or more than likely make my own. What a disappointment.

 

[Turbo Monk3y]

I bought mine years ago, I think I had revision 1 of the K-sports, right at the 1 year mark exactly 3 days after the year mark, the Rear passenger just started leaking oil horribly. I couldnt get anything replaced under warranty. So now I just drive around with a leaking/almost blown rear pass strut. Good thing I don't auto X or road race this thing. I am also in the market for new Coilovers that will at least last a few years for both my 95 DSM and my 93 MR2 turbo..

 

[Rob10_99]

What are the shocks supposed to have for travel?
And how much does stock have, like 6"?

 

[pboglio]

I have these very same coilovers. There is a big difference between soft and hard, especially in the rear. If your bottoming out, something is very wrong.
More than likely you've adjusted the rebound/dampening on the high side, ESPECIALLY in the rear. This will feel like your hitting a bump stop HARD. Think about it, you would need a pretty serious impact to use up 2" of suspension travel OR extremely high corner g-loading, especially with these higher rated springs, don't know which your experiencing. However, dampening on full stiff on the rears will feel like you dropped the car off a building when you back off your drive way. Don't know if this is your problem but it was on mine and dialing them in isn't a 5 minute affair, took me several weeks to get a relatively decent adjustment.

I'm not saying these are the best coilovers, but I've got them dialed in "ballpark" and they don't crash flying over railroad tracks and they still have very good handling characteristics. What do you expect for ~$700?

 

[Dallas J]

Depending on how sticky your tires are and how much front camber you have, that rear rate is too high. On street tires itll probably work, but R-compounds and dot slicks will end up causing alot of instability at the limit and in transition.

BTW, this is just IMO and from what Ive experienced on my car. YMMV.

 

[deth2u]

I have these very same coilovers. There is a big difference between soft and hard, especially in the rear. If your bottoming out, something is very wrong.
More than likely you've adjusted the rebound/dampening on the high side, ESPECIALLY in the rear. This will feel like your hitting a bump stop HARD. Think about it, you would need a pretty serious impact to use up 2" of suspension travel OR extremely high corner g-loading, especially with these higher rated springs, don't know which your experiencing. However, dampening on full stiff on the rears will feel like you dropped the car off a building when you back off your drive way. Don't know if this is your problem but it was on mine and dialing them in isn't a 5 minute affair, took me several weeks to get a relatively decent adjustment.

I'm not saying these are the best coilovers, but I've got them dialed in "ballpark" and they don't crash flying over railroad tracks and they still have very good handling characteristics. What do you expect for ~$700?

Neither of us could feel a difference in either damping rates on opposing side of the spectrum. This is hard to believe, especially when there's supposedly 16 rates to choose. This isn't the impressions while driving, this is off the car in a vice applying compression and rebound force.

My car is practically a race car with tags and plates. There's a lot more force to be absorbed bumping over a railroad crossing at street speed, than barreling into a poorly surfaced canyon road at 80 mph. With a limited suspension travel, I believe it's going to limit the functionality of the stock stabilizer bars.

I chopped the top because I like to cruise around every now and then, in case anyone was wondering You more than right about getting what you pay for though; I made a mistake picking these up. If you wouldn't mind, I'd like to see if your damping rates are like this as well, but you'd have to disassemble the suspension.

Depending on how sticky your tires are and how much front camber you have, that rear rate is too high. On street tires itll probably work, but R-compounds and dot slicks will end up causing alot of instability at the limit and in transition.

BTW, this is just IMO and from what Ive experienced on my car. YMMV.

Noted, thanks. I'll see how it pans out on the spare set of a046s, then R compounds after they wear out

 

[pboglio]

Hmm, cmon now, you know either you install these things on a shock dyno, or you put them in a real world scenario. I agree the soft to hard settings are way non-linear, but I can ride soft on the rears and feel perfectly fine, or I can set them so hard one good deep pothole would split that strut like a ripe banana. I prefer to maintain traction while cornering as the rear stiff setting simply makes the rear end skip in mid air.

I'm not gonna dissassemble my suspension, why don't you just install the coilovers the way they were meant to. I seriously want to see how you can compress a strut fast enough by hand to simulate a real world scenario, rebound characteristics notwithstanding. I am sure the internal valving is speed sensitive and the internal fluid drag thru the valves only is going to occure at high compression speeds, like while your driving. Somebody with strut-background needs to step in here.

 

[Dallas J]

Noted, thanks. I'll see how it pans out on the spare set of a046s, then R compounds after they wear out

Cool, definately post the results with different tires. Im collecting my own data to find out what rates work with the 2gs well. For my car Ive settled on spring rates based on a 2.2-2.3hz natural frequency which works great on 275 V710s. On my 235 KDW street tires they tend to understeer more. I think more rear bar would be the fix, but itll be interesting to see your results.

 

[deth2u]

Disassembled another one a bit farther

They are rebound adjustable only, not both as claimed. There is absolutely no change in damping force on compression, however rebound gets pretty stiff. Not as stiff as the KYB AGX on #4 (rock on a stick). I'm not sure why the left side was acting differently, I'm going to have to look at that again. I hope it's not jacked up.

Specs:
3.4" total shock travel, free length to bottom out
Bump stop height: 1.35". Probably can be trimmed a bit safely for extra travel.

The 2" travel measurement stands. This is before static sag when the car is put back down (will vary on mass, spring rate and preload). In actuality, you're really only getting 1.xx inches of suspension travel before you're on the stop.

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[Red97Eclipseboy]

I've never owned these, nor will I, but I have been in a 2g GSX that had these and the ride-quality was awful. Even on soft. Pboglio, what different suspension setup than the Ksport's have you had?

 

[steve]

I don't know jack about suspensions but 3.5" of total travel is a joke. The stock shocks had about 6" up front and about 7" in the rear (depending on AWD/FWD MTX/ATX). Springs need room to work even ones with skyhigh rates.

 

[pboglio]

The stockers also have a progressive spring rate, which is why they need the extra travel. The travel being short is eye-opening, but I haven't come against a situation on the street where I could detect that they bottomed out.

I don't know on a roadcourse with massive sticky R-compound tires and high-g loading on a very rough surface if you wouldn't be on the bump stops, which would NOT be good I can wholeheartedly agree, but then again somebody would have to have had ACTUALLY tested them out in that situation before complaining about them.

 

[RipperXX]

pboglio, could it be you are just defending your purchase? 2" of travel is a joke, I don't care what the spring rates are. For a street driven car thats ridiculous.

 

[treebonker]

K-Sports force vs displacement
K-Sports force vs velocity

That dyno plot is 2 years old. They say the internals have changed since but many still consider them as an expensive set of pogo sticks.

 

[jjgrizz73]

pboglio, could it be you are just defending your purchase? 2" of travel is a joke, I don't care what the spring rates are. For a street driven car thats ridiculous.

Possibly, but I also purchased these and can say I never onced bottomed out...I dont have the ride too stiff so my tires rub and I can smell some tire going over large bumps (thanks NEPA) but have never once bottomed the strut out...

 

[black_gst]

i have a set of these but the 36 way adjustable. i have noticed that there is alot less travel then factory or less then my blues i had before. i also noticed that they hardly sag once you put the car on the ground where my tokico blues/eibach would drop 2+ inches once the actual weight was on the wheels. maybe they were just old...

 

[pboglio]

pboglio, could it be you are just defending your purchase? 2" of travel is a joke, I don't care what the spring rates are. For a street driven car thats ridiculous.

That pathetic 2" of travel at the strut is more like 3" at the centerline of the wheel on a 2g suspension. If you plan on jumping curbs or entering in the Baha 500, then these aren't for you.
Nah, I just don't have tolerance for bullshit. Read my previous posts, I defend nothing if it doesn't perform. I'm not arguing all the measurements, but to attempt to quantify compression and rebound characteristics on a bench vise, I don't agree with and I'll leave it at that.

Mine have 36 way adjustability, spring preload, ride height adjustment, and if lowered require some SERIOUS attention to bringing toe and camber back into spec. There is enough here that if you just slap them on they WILL ride like ass. Spend a few weeks dialing them in, getting a new alignment, camber adjustment kit, and you'll start to understand my viewpoint.

Maybe my perception of handling is mental, but I'll tell you one thing: I've used my 05 STi as a benchmark for dialing in these K-sports and the handling characteristics up to a point are ballpark, with the STi just having better at the limit confidence due to the active differentials. I can't wait to drop in some RM sway bars and then I could dial back the compression settings a little more for a completely cush ride. Like I said, you got to tune the suspension.

And yes, if you lower these babies, you will be rolling the rear fender on a 2gWTF

 

[Turbo Monk3y]

I have never bottomed these things out, All I said was that the revision 1s of these K-sports suck as far as taking abuse on the street. All revision 1s leaked. Hell they did not even have 2 sets of different coil overs when I bought mine. Now K-sport has a few different sets to choose from and they have been revised and are most likely better.

I just ran a 10.84 @ 135 @ 27 psi on Saturday with the rear passenger side strut section slowly leaking fluid. The springs are stiff enough not to have them bottom out.
The Previous pass was a 10.88 @ 131 @ 24psi with a 1.61 60ft. I have my car lowered to 1 finger gap up front and a 1.5 fingers in the rear, with the fenders rolled I never make contact with the tires so they still do their job surprisingly.

here is a pic of the side that leaks

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and 2 of the 17X8.5" +30 245-45-17s
http://img37.imageshack.us/img37/6092/p1010487.jpg
http://img46.imageshack.us/img46/72/p1010464.jpg

The rears rubbed a tad over huge bumps before the fender roll, hence the small marks on the tires.

 

[RipperXX]

I'm not saying the people claiming they don't bottom out on there cars are crazy. I am just saying theres no way that 2" of travel is optimum for a street car. (again IMO) A track only car could likely be dialed in to deal with it just fine. But on the street IMO it's a bit lacking.


IMHO 3.5 to 4" should be present in a street suspension. Just this guys opinion. If it works for you, and your happy...then well it works for you and your happy *shrug*.

 

[Lumix315]

I own these and I have to say...Wow. This news is surprising to me, seeing as though before I came across this thread tonight, all the reviews I've read in the past on these coilovers have been good. No one has had any complaints about them and they have been considered a great bang-for-your-buck suspension setup.

I agree with pboglio when he says that he'd like to see the results from actually being installed on the car. I'm curious now...

 

[gpz750]

I had these too. They sucked, car rode like crap no matter how they were adjusted. Always seemed to bottom out. I went back to illuminas and it's ALOT better. K-sport customer service also sucks. I got the wrong spring rates first after asking for a specific rate. They said they would make it right but never did. Dumb me bought another set thinking I could get the right rates, got the same crap I already had. They wouldn't take them back or swap them even though they had never been mounted. Was told just to change the springs when the tech section clearly stated they needed to be revalved. What a joke of a company to deal with. The coliovers might be ok for racing, but suck on the street.

 

[slow4g6392tsi]

I have them (also purchased from JNZ a while back) and I think that they are junk. The black piece that screws into the bottom vibrated loose, unscrewed itself, and fell out luckily I was in a parking lot when that happened. The locking pieces keep coming loose for height and stiffness. It seems like no matter how stiff or soft I adjust them, the car still doesn't ride that great. I would no recommend them to anyone. I'll be changing them out for something else sometime this winter hopefully.

 

[pboglio]

I've heard from countless people who have blown these struts telling me they suck. My own neighbor with his pretty little EVO IX couldn't handle the Megans (clone to the K-sports). Knowing him, I can believe it since he's a newb to anything mechanical. Then he sits there and has the balls to tell me how crappy my K-sport coilovers are, when he has no conception of what a coilover even is. Lets repeat, "THEY NEED TO BE ADJUSTED PROPERLY". Read Road Race engineering's EVO website on the JIC coilovers, RRE Eclipse JIC Coil Over Suspension Info

Blowing a strut isn't a problem, go ahead and turn the rear coilover compression/rebound adjuster to full stiff, then proceed to daily drive it to work for about a month. If you survive with all your teeth still intact, you should have ended up with a blown strut.

 

[gpz750]

Even IF and thats a big IF they were not adjusted right that doesn't do anything for customer service. I worked with mine for awhile called k-sport for help( they never did). Never could get it to the point where I didn't want to cut my kidneys out. I will say it was like a slot car in the corners, but not worth it for a daily driver.

 

[black_gst]

I'm not saying the people claiming they don't bottom out on there cars are crazy. I am just saying theres no way that 2" of travel is optimum for a street car. (again IMO) A track only car could likely be dialed in to deal with it just fine. But on the street IMO it's a bit lacking.


IMHO 3.5 to 4" should be present in a street suspension. Just this guys opinion. If it works for you, and your happy...then well it works for you and your happy *shrug*.

ksport does say that this is not street suspension... if you are looking for street suspension try Tokico i had it before and its pretty good