How to test KYB strut out of the car?

jimmyx said:
On the D2s and the Ksports (don't think this applies to GAZ) the damper travel and spring height remain constant. The vehicle height adjustment is handled by the threaded lower mounts and not by compressing the spring. It has the effect of shortening the strut housing without actually shortening or limiting travel. The distributor for Ksport in the US is not up for altering the supplied spring rates claiming that the valving is matched to the springs, so custom matching of components at Ksport looks to be a dead end.

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I prefer that type of coilover, with two sets of threaded adjustments on the housing; one for the spring and a second for the lower strut mount to the car. It allows for individual height and spring adjustments as @jimmyx says. However keep in mind the height adjustment (the lower mount threaded one) is limited to how much clearance there is below the struts, until it hits the rest of the suspension/drivetrain. On the X that is pretty limited (I think about an inch if I recall off hand), so you likely will end up having to adjust the spring height as well if you want a LOW ride height - especially at the front.

Also remember that as the spring lower perch is dropped (as when lowering the ride height that way), you are still reducing the travel regardless of the length of the spring (respectively). So you can still end up with so little travel that it can bottom out.

I would think the double adjustability of the dampeners could allow for compensation with a different spring rate (to a degree), so it surprises me that a coilover maker would not allow you to choose another spring rate (within reason). However you can always buy aftermarket springs in ANY rate and length to fit ANY coilover, and make them what you want.

The noted "modifications" for the top mounts may apply to other coilovers as well. The X's top mounts are rather unusual and reflect the design needs of the front suspension. Most coilover makers get around it by using a "solid" (monoball) top mount, as with the adjustable camber plates on many. That makes for a much harsher ride quality, particularly in terms of transmitting road noise, vibration, harmonics, etc. Those modifications might(?) have been done to alleviate this for a road only application - by adding the stock rubber top mount back into it? Otherwise I'm not sure why they needed to do this as opposed to say making new mounting holes in the strut tower to bolt more generic 'solid' top plate mounts?
 
Dr.Jeff said:
However keep in mind the height adjustment (the lower mount threaded one) is limited to how much clearance there is below the struts, until it hits the rest of the suspension/drivetrain. On the X that is pretty limited (I think about an inch if I recall off hand), so you likely will end up having to adjust the spring height as well if you want a LOW ride height - especially at the front.
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My experience is that you can lower the front a lot more than the rear. The drive shaft is blocking the strut to be lowered as much at the rear. But lowering the car 60-80mm is not a problem.
 
Dr.Jeff said:
I prefer that type of coilover, with two sets of threaded adjustments on the housing; one for the spring and a second for the lower strut mount to the car. It allows for individual height and spring adjustments as @jimmyx says. However keep in mind the height adjustment (the lower mount threaded one) is limited to how much clearance there is below the struts, until it hits the rest of the suspension/drivetrain. On the X that is pretty limited (I think about an inch if I recall off hand), so you likely will end up having to adjust the spring height as well if you want a LOW ride height - especially at the front.

Also remember that as the spring lower perch is dropped (as when lowering the ride height that way), you are still reducing the travel regardless of the length of the spring (respectively). So you can still end up with so little travel that it can bottom out.

I would think the double adjustability of the dampeners could allow for compensation with a different spring rate (to a degree), so it surprises me that a coilover maker would not allow you to choose another spring rate (within reason). However you can always buy aftermarket springs in ANY rate and length to fit ANY coilover, and make them what you want.

The noted "modifications" for the top mounts may apply to other coilovers as well. The X's top mounts are rather unusual and reflect the design needs of the front suspension. Most coilover makers get around it by using a "solid" (monoball) top mount, as with the adjustable camber plates on many. That makes for a much harsher ride quality, particularly in terms of transmitting road noise, vibration, harmonics, etc. Those modifications might(?) have been done to alleviate this for a road only application - by adding the stock rubber top mount back into it? Otherwise I'm not sure why they needed to do this as opposed to say making new mounting holes in the strut tower to bolt more generic 'solid' top plate mounts?
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"However keep in mind the height adjustment (the lower mount threaded one) is limited to how much clearance there is below the struts, until it hits the rest of the suspension/drivetrain".

That would be the case if the coilover and the stock front strut were the same overall length, but the unmounted free lenght (bottom of shock tower to bottom of strut) of the stock strut is about 20" and the D2 or Ksport is about 15" so there is no issue with drop utilizing the lower mount and there should never be a need to adjust the spring height. Performing a radical drop may look good on a static display, but real world street driving requirements usually wins out over visuals. I found a pic of a front unit mounted that shows the distance quite well. The rear is a different animal altogether as the stock strut and the coilover are similar in length and the axle shaft directly under the strut is the limiting factor.

20190525_145334.jpg
 
Dr.Jeff said:
I did not realize that. So the front can definitely be dropped as much as desired. That's good to know. I wonder how it compares with other brands of coilovers for the X?
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It seems like the few X-heads that has either D2 or Ksports are happy with them. They have something for most every strut equipped application so there are lots of good web reviews of both brands, but just as many negatives reviews too - though not necessarily X specific. The quality of the Ksports looks to be good, but the K20 project they are going on is at least 6 months away from hitting the road so can't really say. I take most of the negative comments with a grain of salt. Deviating from stock suspension components is a delicate dance and poor results are usually influenced more by owner/operator error rather than component quality. For those wondering if this type of coilover is a good lowering solution; it certainly is for a purpose built car, but would I ever consider these for a stock to mildly warmed over street car? No. It's not a matter of price as the Ksports are about the same as the upgraded set offered by Vick. The creeks, pops, snaps, and groans are fine once in awhile, but for extended driving/cruising it can get old fast and there are far better alternatives offered by MWB or Vick. For a high H.P. build the D2s or Ksports are a good option, and their noise will be hard to hear over all the other mechanical music you'll be generating. In my stock '77 I have KYBs with bigfoot plates, stock springs, and new stock rubber top mounts and it sticks like a cat on velcro with ride comfort as Fiat intended. In the end it's all about the build objective.
 
jimmyx said:
On the D2s and the Ksports (don't think this applies to GAZ) the damper travel and spring height remain constant. The vehicle height adjustment is handled by the threaded lower mounts and not by compressing the spring. It has the effect of shortening the strut housing without actually shortening or limiting travel. The distributor for Ksport in the US is not up for altering the supplied spring rates claiming that the valving is matched to the springs, so custom matching of components at Ksport looks to be a dead end.

View attachment 41366
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I see 😀, the lower mount screws in on these, very nice! That would allow you to lower the car without making the strut housing too long. And, they do valve the strut to match the spring rate. I like that too, unless you are limited in the spring rates offered?
Other than adjusting the toe and caster when you lower the car you should be aware of how lowering the car affects the camber curve, or gain. Stock, the lower control arms point down when you look at them from the mounting point on the chassis to the ball joints. As you lower the car that angle tends to level out, or, even flip so they point up if you really lower the car. When the control arm points down, you gain camber as the control arm moves up through the arc of it's travel, until it goes horizontal. Once it reaches horizontal the camber change goes negative as the control arm arcs up. That means the contact patch on the tire is reduced, which isn't good for handling. You could compensate for this affect by moving the inner control arm mounting point up on the chassis as much as the car was lowered. But most folks don't want to go to the trouble of doing this (plus you should move the front strut rod mounting bracket and steering rack up an equal amount too). To limit the camber - loss - as a lowered car's control arm goes through its arc (from horizontal to the ground to pointing up), most folks fit stronger springs. That limits the amount of control arm movement (up) as the weight is shifted to that corner. Problem with that is that heavier springs aren't very "streetable".
Moral of the story - Don't lower your car so far that the control arms point up. While lowering your car looks good, it doesn't necessarily mean your handling will improve. You have to pay attention to how lowering your car affects your dynamic alignment (yes, it affects bump steer too) if you want to optimize handling.
 
jimmyx said:
It seems like the few X-heads that has either D2 or Ksports are happy with them. They have something for most every strut equipped application so there are lots of good web reviews of both brands, but just as many negatives reviews too - though not necessarily X specific. The quality of the Ksports looks to be good, but the K20 project they are going on is at least 6 months away from hitting the road so can't really say. I take most of the negative comments with a grain of salt. Deviating from stock suspension components is a delicate dance and poor results are usually influenced more by owner/operator error rather than component quality. For those wondering if this type of coilover is a good lowering solution; it certainly is for a purpose built car, but would I ever consider these for a stock to mildly warmed over street car? No. It's not a matter of price as the Ksports are about the same as the upgraded set offered by Vick. The creeks, pops, snaps, and groans are fine once in awhile, but for extended driving/cruising it can get old fast and there are far better alternatives offered by MWB or Vick. For a high H.P. build the D2s or Ksports are a good option, and their noise will be hard to hear over all the other mechanical music you'll be generating. In my stock '77 I have KYBs with bigfoot plates, stock springs, and new stock rubber top mounts and it sticks like a cat on velcro with ride comfort as Fiat intended. In the end it's all about the build objective.
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Earlier when I said I wonder how they compare to other brands of coilovers, I was referring to the length of the body at the lower end...in terms of clearing the rest of the suspension. I don't know if the others are as short as these to allow that much lowering (with the adjustable lower mounts).

@Bjorn Nilson , do yours have a threaded lower mount adjustment like this? And how does the length of the body compare at the bottom.....
20190525_145334.jpg
 
@Dr.Jeff, My mount is also threaded.
Front with lots of space for lowering:
IMG_20210118_124714.jpg


Rear (wrong orientation):
I can lower it another 20-30mm if needed, but If lowering more than that , the damper will hit the CV joint. But as mentioned earlier, it is possible to lower the car at least 80mm from stock with D2 coils.
IMG_20210118_125019.jpg
 
Got an answer back from GAZ.
"Unfortunately the GHA kit has no damping adjustment only height as this is due to the fact the top of the piston rod where it bolts to the mounts is too small in diameter so this means we can not drill through the centre of the rod where the adjusting rod will be as it will not leave enough material & they will be too weak. For any type of motorsport we would suggest the Gaz Gold kit & we can supply them with the spring rates you require although the front may want to be slightly stiffer. I have attached a picture of a Gaz Gold strut & although not for your car you can see where the adjustment knob would be."
Cost: 1,495 Pounds Sterling (approx. $2,000 US) + shipping for a set of 4 GAZ GGA. I'll keep looking for something a bit more affordable.
 

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Alain said:
Unfortunately the GHA kit has no damping adjustment only height
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If you are looking for low cost coilovers, maybe K-sport is an alternative? I've been in contact with people with K-sport coilovers and they are happy with their "Street" coils. They mean that no modifications was necessary to have them fitted. -K-sport is low cost (1490 USD) but fully adjustable like D2 (except caster). However, I don't think you can order specific spring rates with the K-sport kit.
 
Bjorn Nilson said:
If you are looking for low cost coilovers, maybe K-sport is an alternative? I've been in contact with people with K-sport coilovers and they are happy with their "Street" coils. They mean that no modifications was necessary to have them fitted. -K-sport is low cost (1490 USD) but fully adjustable like D2 (except caster). However, I don't think you can order specific spring rates with the K-sport kit.
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Thanks Bjorn. When you say "people with K-Sport coilovers", do you mean X1/9 owners?
 
Alain said:
KSport says they do not make a kit for the X1/9.
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Go through the US distributor, not the parent company in Germany. I just picked up a set a couple of months ago. The cost was $1,345 plus about $50 for shipping. Bjorn is correct, the spring rates are what they are, but springs from all the usual sources are easy to find and not very expensive.

ksportusa.com

Ksport USA - Aftermarket Suspension and Performance Parts

Ksport is the leader in aftermarket suspension and performance parts including coilovers, air suspension, big brake kits, and more.
ksportusa.com ksportusa.com
 
Alain said:
KSport says they do not make a kit for the X1/9.
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I know nothing about them but are supposed to be an authorized US distributor (located in New York) for D2.

D2 Racing Coilovers

D2 Racing is a world leader in suspension applications including their world famous coilovers, new patented air suspension, affordable lowering springs and much more! Call us today at 855-998-8726!
www.d2racingcoilovers.com www.d2racingcoilovers.com
 
Alain said:
Thanks Bjorn. When you say "people with K-Sport coilovers", do you mean X1/9 owners?
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Yes, they are X1/9 owners. D2 and K-sport are the only two alternatives available for X1/9 in Sweden. When I spoke to the Swedish K-sport reseller, he meant that welding (???) is necessary to have them fitted. But when talking to two X1/9 owners here they say it is a direct fit. Obviously the reseller knows nothing about our cars.
 
Bjorn Nilson said:
Yes, they are X1/9 owners. D2 and K-sport are the only two alternatives available for X1/9 in Sweden. When I spoke to the Swedish K-sport reseller, he meant that welding (???) is necessary to have them fitted. But when talking to two X1/9 owners here they say it is a direct fit. Obviously the reseller knows nothing about our cars.
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Sadly it is common to get misinformation from companies like that. Oddly they are only hurting themselves for not taking the time to find the correct answers.

Unfortunately the web sites for many companies are no better. They often don't offer much information, or worse - incorrect information - about their products. We already saw an example of that with the K-sport listings for the X1/9. And even when the listing was found it really says nothing about what the units are.

There is a lot of great information on coilover options in this thread. Frankly something that has been lacking or scattered about in the past here. I hope we continue to get more input so others can benefit from it. Thanks to those who are researching the companies and products, and taking the time to post their info.
 
jimmyx said:
Here is the part # for reference - page is from Ksport Germany. The US sales manager's name is Eric and he knows exactly the kit you are looking for.

www.k-tec-germany.com

K-Sport Fiat Bertone X1/9 (128 AS) Coilover Street - K-tec Germany

The FIAT Bertone X1/9 128 AS coilover kit for street and motorsport: adjustable pillowball top mounts, damping adjustment, length adjustable struts & damper
www.k-tec-germany.com www.k-tec-germany.com
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That's exactly what I did, US KSport. Here's the reply:
Thank you so much for reaching out! Unfortunately we do not make any kits for your vehicle, I apologize. If you have any other questions feel free to reach back out, have a great day!
Thank you,
Chase M

I will reach ou to Eric.
 
Alain said:
That's exactly what I did, US KSport. Here's the reply:
Thank you so much for reaching out! Unfortunately we do not make any kits for your vehicle, I apologize. If you have any other questions feel free to reach back out, have a great day!
Thank you,
Chase M

I will reach ou to Eric.
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Here is the full contact info:

ERIC DAYTON
Account Manager
A: 254 W Broadway Rd., Mesa, AZ
P: 480.829.8100
W: ksportusa.com DIRECT EMAIL: eric@ksportusa.com

I would make sure to tell him what his people are telling you. Amazing how these vendors stay in business sometimes?
 
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