Koni/Progress vs Tein Street Flex

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Koni/Progress vs Tein Street Flex

Post by JacksonG114 »

I have a 07 NC1 and have been researching and debating several suspension upgrade choices for a while. I was wondering how the Koni/Progress with new bumpstops, RB or Progress sways and new endlinks compares to the Tein coilovers. I know on the product page for the Teins it mentions upgrading the front sway, is that to reduce oversteer? I have never replaced suspension before, but it doesn't look too difficult, so I like the easiness of the Teins, but don't know how they compare. I don't track the car, but might autocross in the future and am not super concerned about NVH.


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Re: Koni/Progress vs Tein Street Flex

Post by Brian »

The Koni/Progress combo is a fun street setup, still SOFT compared to something like the TEIN coilovers.

So, if you really think you might autocross then the TEIN is going to be MUCH FASTER. There are some other advantages of real coilovers like the TEIN...which include that you can set heights to whatever you want....and later raise or lower, you are not 'stuck' with the heights you get. Also, the bodies are shorter such that on a lowered car you end up with more travel...and what that translates to is that the ride quality with the much higher spring rate TEIN coilovers is really about the same as the much 'softer' Koni/Progress combo because with the TEIN combo you have more compression travel before you hit the bumpstops.

Yes, with the TEIN you get more oversteer than many want and the usual answer for that for autocross customers is a big upgraded front sway. However, if the budget doesn't include the upgraded front sway in addition to the coilovers then the other way to accomplish the same re-balance of the car is to simply remove the stock rear sway bar (this way of doing it not as FAST around an autocross as going with higher rate front bar but at least balance is easier for the average driver).
Brian Goodwin
Good-Win Racing
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