Ark GT-F springs installed

[raztah022]

I thought that I would post some pics for you guys to use as a source of reference. I also have 20mm wheel spacers. Please keep in mind that it hasn’t settled yet though. I had GT-S springs on my G80, and I thought that the drop was just a little too aggressive for my taste.

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Hello, how much drop do you think is the difference between the GT-S and GT-F. Their website does not specify how much drop for the GT-S . Thanks in advance

 

[Slip_Angle]

So... I'm thinking about removing the Ark GT-F springs and returning to stock.

Really, the only reason is that with the shock compressed, I find the suspension crashes over rough roads. Where I live, the roads are terrible. Unless I can figure out another solution to prevent it.... but I can't think of anything. These springs are fantastic in every other way but the shocks are bottoming out on occasion and I'm worried something is going to break.

For anyone thinking about these springs, don't let this post give you a negative feeling about them. They are great! Again, it's just the roads where I live and with the shock more compressed, the remaining travel isn't always enough.

 

[Husky]

The car could use stiffer dampers. I wish there were some good options (other than coilovers).

 

[Volfy]

Ark GT-F's 0.75" drop isn't too far off Eibach's Pro Kit springs. Should still have a good amount of travel. Did you trim the stock bump stops?

With aftermarket modifications in the past, I find that most of the harshness comes from stiffer shock valving and not as much from lowering springs (assuming moderate amount of lowering). Both our G70 and Stinger are still quite plush with Eibach springs. About the only times I notice the difference is when going over speed bumps.

 

[Slip_Angle]

Ark GT-F's 0.75" drop isn't too far off Eibach's Pro Kit springs. Should still have a good amount of travel. Did you trim the stock bump stops?

With aftermarket modifications in the past, I find that most of the harshness comes from stiffer shock valving and not as much from lowering springs (assuming moderate amount of lowering). Both our G70 and Stinger are still quite plush with Eibach springs. About the only times I notice the difference is when going over speed bumps.

No, Ark says not to trim the bump stops.

 

[Volfy]

Hmm... I wonder why the discrepancy. Eibach was very specific with the trim instructions:

I have no reason to doubt Eibach. Bump stops are there for a reason. Judging by how much the drop is for my cars:

G70 2.0T RWD: 0.7"F 0.6"R
Stinger 2.0T RWD: 0.8" F 0.8"R

I'd say 20mm F and 30mm R are spot on.

 

[Slip_Angle]

@Volfy - Dude, really appreciate your post!

I spoke with Ark and they said it's optional to trim the bump stops but makes sense to do it in my case. He said 1/4 inch should be good...hmm

I think this may solve the problem. The amount of shock travel has been reduced, so a small pot hole or rough road would use up that limited travel quick.

I should be able to do it with them on the car. I'm all ears for any tips.

Thanks again!

 

[Volfy]

Glad to help.

Understand it's a royal PITN to R&R everything just to trim the rubber foam bump stops, but I don't think it's possible for the front struts. The bump stops are inside the dust cover.

For the rear shocks, it should be possible. I just cut it right at the first notch, which is very close to 30mm. Go slow so you don't score the shaft. Rotate the bump stop as you go to make it easy to cut. Your biggest hurdle is to attach the dust cover back on to the second notch. For me, with it off the shock, it was very easy to do with a big flat blade screw driver. Might be a tad more difficult on the car, but you should be able to do it.

Trimming 1/4" seems like a pointless exercise, IMO. There is next to no downside to trimming 20mm/30mm per Eibach's instructions. Even if I were to go back to stock springs (I don't see why I would want to, at this point), all I'd do is buy a set of replacement bump stops. And that's only if I plan to continue driving the car that way and am worried about bottoming out the shock internal pistons with the shortened bump stops, which is highly unlikely. I compressed the shocks while they were out of the car, just to test how soft they are, and they have more travel than trimmed bump stops would allow.

 

[Husky]

Good idea to have checked that. Makes sense to trim them.
Can you post a side view pic to see how the drop looks?

 

[Slip_Angle]

I haven't looked yet but I figured the dust boot could just be pulled down and then trim the bump stop. Maybe that's easier said then done....?

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[Volfy]

I haven't looked yet but I figured the dust boot could just be pulled down and then trim the bump stop. Maybe that's easier said then done....?

Now I think about it... you might be right. I just remember when I took the strut apart, the dust cover came off with the top strut bearing/mount assembly. I didn't bother to pull off the dust cover, since there was no need to, so I didn't pay attention to how the dust cover attaches to the strut top assembly. IIRC, the bump stop is jammed up into a recess on the under side of the strut mount assembly. So... if you can manage to pull down the dust cover, then yes, you should have access to the front bump stop. Worth a try.

Sorry I didn't take any pics both times when we worked on the G70 and Stinger. Usually by the time we got to that point, we're sweating and cussing and just wanted to get it done and over with.

 

[Slip_Angle]

I took a look at lunch and yep, the dust boot pulls down and the bump stop is accessible. Whew!! Should be relatively easy but like you said I want to be careful to not score the piston.

I agree with you on how much to trim. If that is what Eibach does for theirs, it's obviously safe. I will do it this evening and provide an update here.

 

[Slip_Angle]

Good idea to have checked that. Makes sense to trim them.
Can you post a side view pic to see how the drop looks?

 

[Volfy]

Can you post a side view pic to see how the drop looks?

Just realized I don't have a static side profile shot of the G70 after the suspension mods. I just asked my son to take some pics and will post them.

Here is a shot of the car prior to the suspension mods. From inside the car, neither my son and I realized just how much the car pitched and rolled around the course... until we saw this pic. I ordered the anti-roll bars and springs the next day. I've always preferred to keep my cars stock and modify only as necessary. This... was abso-freaking-lutely necessary!

 

[Slip_Angle]

Wow - even my old EP3 Civic didn't roll that much at autocross. Those outside tires are putting in the work lol

 

[Volfy]

Especially that poor outside front! Taking the tires off after the event and comparing tread wear of all 4 confirmed what you can clearly see in that pic. Not only were we wasting a good bit of tire traction with that much weight transfer, all the pitching and rolling upset the chassis and slow down side-to-side transitions.

I would've preferred to stay in Street category, but a better handling car makes for a better learning tool.

 

[Husky]

I'll bet it's nice and much better with the springs and bars.
I have to decide how long I think I'll keep it before I spend the money and effort to do the mods (of course it's already been 3.5 years, haha). I'm sure I'd enjoy them, as long as it isn't too stiff/harsh, since our roads aren't great. Having the 18" wheels and tires helps though.
I was toying with the idea of replacing it with a used Panamera (2nd gen), but they're still so damn pricey.

 

[Slip_Angle]

^^ Love the Panamera

Alright. I jacked the car up and pulling the dust cover down was easy. Making it stay down required a couple of zip ties. I then used a razor and cut the bump stops 20mm or so... I found holding the razor still and rotating the bump stop worked. My hands cramped up several times because of the angles but overall pretty easy!

Thanks again to @Volfy for the suggestion. I hadn't thought of it at all. I went for a drive and hit the bump that usually causes the *thud* and sure enough, no noise!

..oh and I didn't do anything to the rears.. not sure if it's worth it but for the sake of consistency, I probably should..

(Don't mind it being caked in dust. I washed my car yesterday and went straight to a car show, where I wiped it down buttt the show was down a dirt road - ugh)

 

[Volfy]

I'm just glad that you didn't undo a very worthwhile mod because of a little oversight on the aftermarketeer's part. Especially when it's not your fault for following mfr's instructions. Ark really should've done a little homework IMO.

If you are not getting much bump harshness in the rear, there is no big hurry to trim the stops, though it's probably prudent that you trim them eventually. There rear end is more sensitive to load, so if you drive mostly lightly-loaded commute miles, you're okay as is. The front OTOH has to deal with compression from brake dive, lateral weight transfer, and road undulations... especially with the heavier 3.3T engine up front.

BTW, I do love the Panamera, ever since Porsche intro'ed it. It's really why I bought the Stinger, which I affectionally call my Kimchi Panamera. At this point, I don't see what a Porsche can do that the Kia couldn't, other than the prestige factor. But if Genesis prices don't eventually come down from this current supply chain madness, and/or they really do go through with their wholesale switch to EV, I may go back to looking at the Stuttgart Prancing Clydesdale.

 

[Slip_Angle]

Update:

I found cutting the bump stops improved the suspension crashing but not enough that I was comfortable going over dips, high spots or moderate rough spots. I still had to slow down for these imperfections in the road or risk full compression and bouncy rebound or even thuds from the suspension crashing. After reinstalling the stock springs, I could feel the springs and shocks were better matched and the level of suspension control had improved. Now that I've had the stock springs back on for a couple of days, I don't even notice the road imperfections I used to cringe over. It also feels tighter control wise.

The mechanic that removed the ARKs said they were very soft compared to the stock springs. Compressing then was much easier. My car is an AWD, so a bit heavier but still only 3850lbs. I think ARK should have made these springs the same stiffness as stock and the issue would be moot. Again, just my opinion.

Ark GT-F advantages

• Nice lowered stance
• Lower center of gravity
• Increased lateral handling (Due to lower COG)
• Less body lean (Due to lower COG)

Ark GT-F disadvantages

• Suspension bottoms out over sudden road dips, pot holes etc..
• Reduced suspension control, float and bounce (rougher roads)
• Less stability over harsher roads

TL;DR - My opinion is that the ARK GT-F springs work well on roads that are in good shape and they lower the car to a perfect ride height. Over bumps, dips or rough roads the springs are too soft in the front to maintain the cars weight and allow full compression of the stock shocks. The results are a bouncy ride and suspension crashes.

I would like hear from others on their thoughts and experiences with these springs.