Matching springs/dampening settings

[modulation]

I have Koni yellows and some 350F/250R springs.
From what I read the koni's can only handle about a 450 pound spring.

When I put them on the car I set the koni's at 75% full dampening force because the springs stiffness is 75% of what the koni's can handle. That was just a total guess at what they should be set at.

When I push it hard around corner now it seems to sort of rebounds twice are my koni's set too stiff?
So how does one know when they have dampening set properly?

[mmdb]

koni has a damper setup guide on the net somewhere. try doing a search. btw what do you mean rebound twice? might be the sensation of your diff locking in the corner.

[modulation]

koni has a damper setup guide on the net somewhere. try doing a search. btw what do you mean rebound twice? might be the sensation of your diff locking in the corner.

I guess rebound isn't the right word.
When I use to come around a corner real hard (with stock springs/shocks) the rear body compared to tires would sort of lift up a little and the fall back down (from weight transfer.) Now it does the same thing, but it sort of lifts up again and then drops again but not as much as the first time sort of like how a bouncy ball settles down.

This makes me wonder if the shocks aren't set high enough to match the springs or something. Sorry I'm such a newb.

[djsilver]

What it sounds like he's describing to me is the rear tires catching/slipping/catching/slipping. On stock suspension it can feel like you're in a boat but with stiffer suspensions it's more like a skitter across the track surface. I would suggest backing off of the damping a bit on the rear and see if it will settle down.

[modulation]

djsilver described it pretty well.

I'll turn the rear dampening down to 50 percent from 75% "full" and let you guys know if it feels better.

[DBM]

what springs are you running with those rates? Is it a Ground Control slip over style coilover? Or Is it the ksport/megan springs? I've seen them advertised with a 350F/250R rate, but have also seen them advertised with these other rates: 280F/250R, 220F/180R.
The wire used in them looks to be quite thin and there are a lot of active coils, so I doubt their rates are as high as advertised. Tis a shame, since the 350R/250R rates are decently attractive for a drop-in spring!

[modulation]

what springs are you running with those rates? Is it a Ground Control slip over style coilover? Or Is it the ksport/megan springs? I've seen them advertised with a 350F/250R rate, but have also seen them advertised with these other rates: 280F/250R, 220F/180R.
The wire used in them looks to be quite thin and there are a lot of active coils, so I doubt their rates are as high as advertised. Tis a shame, since the 350R/250R rates are decently attractive for a drop-in spring!

I'm running megan springs.
I will be ordering some 400/350 springs of a quality manufacturer one day, but I don't track all that often and the megans were cheap to start out with.

I'm also going to re-grease all my rear energy suspension bushings to make sure nothing is binding.

[greenman100]

damping, not dampening.

[modulation]

damping, not dampening.

haha I feel even stupider now. At least I won't look stupid in the future (when it comes to this.)
Thanks.

[modulation]

What it sounds like he's describing to me is the rear tires catching/slipping/catching/slipping. On stock suspension it can feel like you're in a boat but with stiffer suspensions it's more like a skitter across the track surface. I would suggest backing off of the damping a bit on the rear and see if it will settle down.

I adjusted my rear koni's today down from 75% to 50% of their max.
That definitely made it way better.

Thanks!

[hai1206vn]

I should to this to mine too. My rear springs are also 250#, with Koni set at about 75%, and it certainly skips sometimes - I guess it's a bit too much rebound damping that doesn't let the inner rear spring droop.

That's said, a lot of rebound does help in autocross with the feel during transition. My rear tire only skips when pushed hard on the street :p

Gah, adjusting the rear shocks is a byotch.

[modulation]

I should to this to mine too. My rear springs are also 250#, with Koni set at about 75%, and it certainly skips sometimes - I guess it's a bit too much rebound damping that doesn't let the inner rear spring droop.

That's said, a lot of rebound does help in autocross with the feel during transition. My rear tire only skips when pushed hard on the street :p

Gah, adjusting the rear shocks is a byotch.

Yeah adjusting the rears ain't fun.
I think they could be set at like 60% instead of 50.
50% is definitely better then 75% though, tires are definitely more planted in transitions.

[hai1206vn]

I took it out for a spin to confirm and I was actually wrong: the skipping happens at the front outer corner. My problem is somewhat soft front springs and not enough camber; the rear is fine.

Don't trust the percentage w.r.t your spring rate compared to 450#. It's all about trial and error.

My car is s14 with an lsd, so that does help quite a bit.

[Def]

You might be running out of travel up front. Do a ziptie test on the strut shaft.

[hai1206vn]

Yea I think so. I have 300# front springs with about 2" bump travel. Still finding a job so no major upgrade for a while.

[modulation]

Yea I think so. I have 300# front springs with about 2" bump travel. Still finding a job so no major upgrade for a while.

I hit my bumpstops alot with just koni's in stock struts. I bought "D'Rex koni strut extenders" for $40 which are for WRX's but worked great for my 240sx. It gave me another .9" of bump travel easily, and I never seem to hit my bumpstops unless I go over some crazy-pot hole I should have been watching out for.

[hai1206vn]

It's probably a must for your Megan springs, they seem to lower the car quite a bit (almost 2"). Such a drop on stock style struts puts it right on the bump stop. Later on I wanna change at least the front setup to threaded sleeves.