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      04-30-2023, 12:12 PM   #23
bbnks2
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Quote:
Originally Posted by Yvrbmw View Post
I’m not following you here — with a stiffer spring (standard ohlins r&t is 7k), the weight of the front would not compress the spring as much, so it sits higher.


When you preload a spring, you compress it by dialing the lower spring perch upward. Preloading the spring, in this sense, would logically be better than a loose spring when unloading the suspension. Ideally a tender/helper spring would be ideal, but there is no vertical room for that.


I am using whatever bumpstops came with the Ohlins. I may be riding on bumpstops, which in itself is not necessarily bad. Having said that, I am not feeling any unusual sudden increase in stiffness, hopping or loss of traction. I did a fair bit of bumpstop tuning on my Miata when working with FatCatMotorsports, so I think I have a good feeling for what bumpstop engagement feels like. Emphasis on “I think”. Could be totally wrong.

I also did look at the spring specs from the Swift website for useable stroke and maximum compressed length (coil bind). When I was setting up the car and realizing that in order to get the lower spring perch high enough to clear the tire, the 7” spring was compressed a significant amount (~1”).

So, comparing useable compression for two springs based on just the springs themselves is not an equitable comparison to real-world springs: The 6” spring has 3.9” max stroke. The 7” spring has 4.6” max stroke. If the 7” is already preloaded/compressed 1”, then real-world available compression is only 3.6”.
not sure what your point is. you're either binding or down on the bump stops by your own calculations... up to you to decide on how to tune around bump stop engagement. Just stating facts.

you also don't lower the car by preloading the spring. Preload is not good and there is no reason to do it. If you're complaining that the car is sitting higher then preload isn't going to help that, and, yes, you would want to sag the spring to fix the ride height. That is why I said the post makes no sense.

Last edited by bbnks2; 05-03-2023 at 07:36 PM..
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