Spring manufactures commonly use two different ways of describing their spring heights. The most common is the total length of the springs installed at kerb weight. So a spring that is said to be an inch lower than standard factory springs would be shorter (underload) by 1". Because most spring manufactures have standard and heavy duty springs listed it can make a huge difference in the free length and installed length.
In Holden vehicles with upper and lower control arms, 1" generally lowered the vehicles ride height by 2" and a 1 1/2 lower spring would drop the car by approximatly 3".
The second way spring manufactures describe their springs is by the lowered body ride height at kerb weight. A spring listed as 2" lower will lower the ride height by approximatly 2" from standard ride height. If you had a 2" lower spring length installed it would be sitting on the bump stops and have no spring compression during driving and would destroy the front end very quickly, don't get the too confused. So if your asking a spring manufacture to make you a set of springs, make sure your both on the same page in relation to the ride height you would like.
A lot of unaware people order new springs and when they remove their old ones and line them up against the new springs there can sometimes be a difference of 3 or 4 inches between the free lengths and they take them back and argue to the supplier they are incorrect. Its due to the difference between the springs wire size and heavy duty spring rating which effects the installed length.
And one last thing to be aware of, I commonly see owners fitting their own springs at home and haven't been installed correctly. Check to make sure you are fitting the springs in the correct sides. Some spring manufactures mark the springs with O/S & N/S. O/S must be installed in the drivers side and N/S in the passengers side. N/S is short for near side or closest to the gutter, and O/S off side. It makes more sense when you realise the spring people supply springs to left and right hand drive cars. Also insure the springs are installed into the lower control arm correctly. Yes there is a difference between top and bottom and the spring end must line up with the step in the lower control arm or the heights will be out considerably.
I am sure most people on this site will be well aware of the above information but when I had my workshop we would regularly see old cars pull in wanting a wheel alignment and complaining about the ride height, and expected me to fix everything with a quick wheel alignment. Most ignorant owners couldn't be told.
Reply With Quote
Bookmarks