quiet_storm98

iTrader: (48)

So i just installed a set of koni sports on the front of my car along with a set of factory springs i bought off of someone and placed them on the lower perch and somehow now my front end sits extremely high. Beforehand i measured the height from the ground to the top of the wheelwell and it was right at about 27 inches. Now it is sitting at 28 inches. During the install i did have an extremely hard time compressing the springs to the point where the compressor i was using actually got stuck and wouldn't budge when i was trying to remove it so i ended up taking them to a shop to get compressed on. I did notice that the shop didn't quite align the spring on the mount the way the factory ones are...the top coil isn't aligned with the mount properly. Could that be what is causing it to be basically over an inch higher especially considering they are mounted on the lower mount which is supposed to lower it about 3/4 of an inch?

SteveC

When I had my shocks replaced, I had the mechanic "index the springs" to the stock seats, that is the springs were installed exactly how they sat on the old shock.

My ride height stayed the same and the vehicle sits even on the ground (does not sag on either end).

quiet_storm98

iTrader: (48)

yeah thats what i think the problem is just didn't think it would throw off the ride height that much. Guess i gotta take them back off and fix it

stp001

Factory style springs seem to be more than a few inches longer than mainstream lowering springs. I would bet the original equipment shocks had a much lower spring perch than aftermarket shocks. I can't be sure as I pitched mine in the trash without looking back. Either aftermarket springs or cutting the springs you have are your options now. If you decide on lowering springs, educate yourself on the spring rates that suit you best, then don't buy anything that doesn't have rates listed.

quiet_storm98

iTrader: (48)

the koni sports have two options for the spring perch height one is the same as stock and one is slightly lower. Tons of people have ran the konis with factory springs on either perch setting and i had them side by side to my factory shocks and the spring perch definitely isn't higher even on the higher of the two perch settings which can be used. I honestly think since the spring isn't aligned right with the mount it is throwing it off

quiet_storm98

iTrader: (48)

A lil update...drove around some and the car settled a bit. Its now a lil over 27.5 inches but thats still slightly higher then it was stock and definitely too high for being on the lower perch. Honestly debating grabbing a set of stranos instead of fixing the alignment of the stock springs but don't want to lower the car much since the roads here in hawaii suck

stp001

You might want to see if Sam can get you a set of Hotchkis springs. Those are supposed to be a softer spring, but still higher rate than stock. A nice compromise. I am sure he could debunk this info if it is erroneous.

quiet_storm98

iTrader: (48)

if i were to get lowering springs i would definitely either go with strano's or the hotchkiss springs but for now im just gonna fix the alignment of the stock springs. Once they are aligned right my car should be 3/4 of an inch lower then stock which is perfect for me

02TransAm/Batmobile

iTrader: (32)

I never bought into the Koni lower perch mod netting a 3/4" drop. The distance between the two grooves is 10 mm (0.39 in).

quiet_storm98

iTrader: (48)

yeah it doesn't seem very far but there are plenty of pics of people who went from the upper to the lower position for the perch and the drop is noticeable

stp001

The drop ratio from shock to end of control arm is 1.7 10mm at shock relates to 17mm at wheel.

AnotherWs6

iTrader: (17)

Lower perch makes a difference. My car a noticeable rake and I did the heater hose mod in the rear when installing springs and shocks.

smitty2919

Go lower perch with lowering springs if you want to rip off the bottom of your car...

Sam Strano

iTrader: (41)

And do you know the motion ratio?

It's not a linear relationship between perch height and ride height.

02TransAm/Batmobile

iTrader: (32)

That's interesting. Can anyone explain in layman's terms why a 10mm difference translates to a lower ride height? How much travel loss does this 10mm difference amount to?

smitty2919

Google "motion ratio" and do some reading.

10mm at the shock is more at the wheel. Because geometry and mathmaticals.

for example: 2:1 motion ratio is wheel travels twice as far as spring compresses

RevGTO

iTrader: (12)

As mentioned above, the only things I can imagine that would cause this is if the spring was not properly compressed when the upper mount was installed, or if some goof at the shop failed to thread the spring ends fully into the grooves on the upper mount and lower insulator.

I have stock springs on the lower perch and it was a definite 3/4" drop.

AnotherWs6

iTrader: (17)

Pretty sure the bottom of my car is still there boss.

smitty2919

OK chief. I have no idea how you clear speed bumps etc. Ain't my car ain't my problem.

AnotherWs6

iTrader: (17)

No worries there Captain. It is my car, but it isn't my problem either.