Koni Inserts (GC variant)

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Koni Inserts (GC variant)

Post by georryan »

So I've been running Prodrive P1 springs and AGX struts for a while now. I've really liked the AGX setup with their easy to adjust knobs. Although, all the reviews I've read and comparisons between the AGX and the Koni's has usually ended up with the Koni's being graded as a better more comfortable ride. Plus, the koni's adjust rebound instead of dampening, and there is a lot of theory out there as to why this is better. It boils down to I wanted to try it, although I didn't want to spend the money.

My brother has a 2.5 RS that had two blown struts up front. I offered to sell him my AGX's cheap, and then I'd use his struts as housings for some koni's. So we did that, and he is running agx's with SPT springs on his RS right now. His ride quality seems to be a lot better than my car with the AGXs. I felt like the AGX struts had an edge of harshness to them at times, and his little impreza does not seem to have that edge at all. They are still quite stiff when dialed up, but I could never find the perfect medium. The softest setting was under dampened and the next level up felt like the rear was a bit bouncy (this could be a difference in spring design as well).

We hacked up his stock struts and put the konis on my car. With them turned all the way down, I didn't feel like the car was under dampened like the AGXs were. The rebound was a bit soft, though, but still comfortable. I turned them up to 50%/50% and felt like the bounciness in the back of the car was less severe than it was when I ran 2/4 on the AGX. Also, going over bumps was less jaring. I ended up settling with half a turn on the front and 3/4 of a turn on the rear. The ride seems quite smooth and solid over bumps without being harsh.

I have noticed that some of the steering wheel stiffness seems to have dropped (maybe a drop in the dampening strength?) compared to the AGX setup. I did notice the steering wheel stiffness got more stiff as I increased the firmness of the strut, but the koni has less stiffness than the AGX.

The downside is you have to pull the rear seat out to adjust the back struts, and that is a big bummer, but I feel like it was a worthwhile trade off. I don't think I'll adjust them that often.

The dismantling of the stock strut really wasn't a big deal. It took some time to cut each of them apart, and that adds to the install time, but wasn't a big deal, and the actual process wasn't difficult.

An alternate approach I hear is to go with the DSpec struts from Tokiko, but they are a GD inverted strut and would require some different rear top hats than what I had. I think their adjustment is slightly different than the konis as well, but they do have an adapter that can stick up between the seat and the back shelf so you can adjust the rear struts without pulling the rear seat.

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Re: Koni Inserts (GC variant)

Post by Legacy777 »


Thanks for the review!

I too have the AGX's, and while I like them for the most part, I find them a little jarring as well. I have them set one notch below the mid point on both front and rear because even mid point was too stiff. I haven't tried full soft yet. I'm running Whiteline Control springs.

Once I get the car back on the road and have some more drive time, I may do something different with the struts since I don't care for the ridiculous stiff suspension in my older age :)

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