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Help installing Koni Sports.... Spring isolator sleeve won't fit?

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Hey guys, I am trying to install Steeda Sport springs on to Koni Yellow shocks and am trying to reuse the OEM spring isolator sleeves. However, the lower spring perches on the struts do not have quite enough room for the springs to seat properly when the isolator is on. Should I force it somehow?

Thanks for any tips you can share.
Was I supposed to get a new spring isolator sleeve that's a little thinner?

To illustrate, here's how the spring fits into the OEM strut:


And here's the Koni:

Yes, it fits without the isolator... but if I install it w/o the isolator I assume I'm increasing my risk of NVH.
You can use the isolator. Everything will seat up properly once you install the struts in the car and get some weight on them. It might take a day or two to settle. My Steeda springs were the same way and fully seated after I installed the struts and drove the car.

You may need to use an impact wrench to tighten the nut at the top of the strut. I could not properly tighten the nut using the small wrench / big socket method in the Koni instructions.

Are several people using impacts to tighten the strut nuts? I was told this could damage the internal dial, maybe only on the clicking ones like ours.


Phoenix, Az
I sure wouldn't use an impact on these.

I'm replacing my passenger side koni yellow strut (the adjuster is broken/valve seems to be destroyed after a curbing incident trying to avoid a prius who couldn't be bothered to watch for cars around them), and I don't have any isolators on my springs. Never noticed any additional NVH, especially since the strut mounts use such a large rubber isolator up top.
I'm gonna do my best not to resort to that... especially since it's a no-no based on what I can gather from the f-ing terrible Koni instructions.

I was able to get the OEM strut nut off the top using these:

It was the only tool that I could fit in there. I am hoping I can put enough pressure on the nut in order to tighten things back up. That is, if I can deciper the torque specs from the "f-ing terrible koni instructions". :)
I found this thread that said "yes, use the oem isolator". Though it isn't referring to a Koni installation.

Grant 302

basic and well known psychic
Use the isolator and let it pop in/seat under load like mentioned above.

For the top nut, I suggest using an O2 sensor socket or a plug socket with a crescent on the outer hex and a 1/4" drive going through the 3/8" drive hole on the outer socket. I wouldn't use an impact gun.
Thanks all. I did the other side this evening, and the spring (plus isolator) fit better into the spring perch. So perhaps a quality control issue?

Either way I am glad I chose to reuse the isolators. I will check on the springs after a fee days to make sure they seat properly.
I had an issue with getting my Hotchkis spring onto the stock dampers and having the isolator end up in the stock position. Did the best I could and installed them back on the car. It worked out fine.
cosm3os said:
Some torque specs would be nice too!

My Koni Sports (from Strano) came with a silly little insert that showed a table that would let you look up your torque specs for the top nut. The thing is... the top of the strut shaft is a crappy little hexagon with rounded edges. I couldn't find any of my sockets (metric or standard) that would fit it very nicely. I ended up stripping it while trying to torque down to what the sheet recommended. It made me sad.

The rest of the torque specs I got from the 2011 factory service manual

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