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OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Sun Dec 04, 2011 10:35 am
by GT1
Hi,
Has anybody ever fitted OEM 2.5i springs with Spec.B Bilsteins on a GEN4 2.5i sedan?
The ride can be a little harsh with the Spec.B Bilsteins and it sits a little higher at the front too compared to the KYB set up.
I am wondering if fitting the OEM 2.5i springs with Spec.B Bilsteins will give a more comfortable ride and give me back my stock ride height at the front, although it won't handle as well anymore which is a fair enough trade off for me.
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Sun Dec 04, 2011 12:26 pm
by t.renshaw34
I'm fairly sure that both billie springs and KYB springs are the same. So comfort/ride height wouldn't change. (please correct me if I'm wrong)
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Sun Dec 04, 2011 8:09 pm
by GT1
t.renshaw34 wrote:I'm fairly sure that both billie springs and KYB springs are the same. So comfort/ride height wouldn't change. (please correct me if I'm wrong)
Yes, you are wrong. The Spec.B springs have a higher spring rate than the 2.5i springs, so they are firmer.
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Sun Dec 04, 2011 8:49 pm
by t.renshaw34
Yes I was wrong.

. Sussed it out this evening for you with my Subaru mechanic mate. Billie springs are approx 5-7 mm higher than kyb's. Should be a good compromise... Kyb springs on Billie struts.
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Mon Dec 05, 2011 11:31 am
by smythie
GT1 wrote:t.renshaw34 wrote:I'm fairly sure that both billie springs and KYB springs are the same. So comfort/ride height wouldn't change. (please correct me if I'm wrong)
Yes, you are wrong. The Spec.B springs have a higher spring rate than the 2.5i springs, so they are firmer.
It's not a "harsh spring rate" that is the main issue with the harshness of the Bilsteins - it is more stiction and high speed compression damping (i.e. shock related not spring related). If anything the springs may be a little soft if you are intending on driving it really hard
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Mon Dec 05, 2011 12:55 pm
by GT1
smythie wrote:GT1 wrote:t.renshaw34 wrote:I'm fairly sure that both billie springs and KYB springs are the same. So comfort/ride height wouldn't change. (please correct me if I'm wrong)
Yes, you are wrong. The Spec.B springs have a higher spring rate than the 2.5i springs, so they are firmer.
It's not a "harsh spring rate" that is the main issue with the harshness of the Bilsteins - it is more stiction and high speed compression damping (i.e. shock related not spring related). If anything the springs may be a little soft if you are intending on driving it really hard
So you feel that changing out the Spec.B springs with the 2.5i springs with the Bilsteins wont yield a more comfortable ride quality?
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Mon Dec 05, 2011 4:23 pm
by smythie
Only marginally. You will still have to deal with the stiction and high speed compression damping in the shocks, which IMO are the real ride quality issue on that setup
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Mon Dec 05, 2011 8:16 pm
by GT1
smythie wrote:Only marginally. You will still have to deal with the stiction and high speed compression damping in the shocks, which IMO are the real ride quality issue on that setup
Thanks for your input smythie.
Re: OEM 2.5i springs with Spec.B Bilsteins?

Posted:
Mon Dec 10, 2012 10:32 pm
by quanroll
Hi GT1 did you end up pairing stock springs with the Billies? I am looking to do the exact same thing as soon as my Billies arrive from Wheelpower hence would like to know how that worked out for you. cheers