hpfreak wrote:
Odyknuck wrote:
The Main spring (bottom) should be the longer of the two and also have a stronger spring rate then the Tender (top). Typically you want to stay with in 100# of each other. As I recall both of the springs on those shocks were of the same rate. I suspect they were changed to accomadate the heavy V8 motor and may be to high of a spring rate for the Subie setup. The rates should be marked on springs.
this doesnt make any sense to me? from what i know of springs, the longer the spring (more coils) the softer the rate, shorter spring less coils=stiffer rate. im also confused about the position of the springs im not so sure it would mater which ones on top or bottom the softer one always gonna colapse first. im not saying your wrong as im sure you know more about springs than myself. but it just doesnt make sense.
Well, springs are wound with different diameter wire that gives you the pounds per inch compression rate for the coil length. Meaning you can have a 200# spring in any length avalable. The reason you want the longer spring on the bottom is two fold, 1) you want it to have 60% of the shock travel as it is the primary spring that is doing most of the work. 2) you want the shorter spring to use up its length quickly so a transfer to the main spring happens when you need it. The shorter lower spring/rate on top is for handling the small bumps in the terrain. Once it collaspes to the point of coil bind (bigger bumps) the transfer ring takes it out of the picture (if adjusted correctly) then your running on the primary spring. Now lets talk about how numbers work. Spring rate is calculated by this formula:
S1 X S2 divided by S1 + S2
Say for example both springs are rated for 200#. When both springs are in play then the calculated rate would be 100#. Once the top spring transfers the load to the bottom spring then the rate would be 200#. So its easy to say when both are the same rate you would simply divide them by 2.
Now lets complicate it with different rates. Top spring 100# and bottom spring 200# then the calculated rate would be 66.6# per inch of compression when both springs are in play. Once transfered to the bottom spring it is still 200# Simple enough. Hope that helps ya!
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these are the rear 4x4 arms me and dave built , they will have 1/2 ton chevy wheel hubs and the stubs will be machined to work like a micro stub . all the tubing was 1 inch chromoly .
guess who did a fine job on my new bad ass front end .......
my very good freind tonya (aka) ruttrider finished my wire harness and did a great job !!!
just rolled the tires up to her to get a idea of what she will look like . lol
