16 inch lr spring versus 20 inxh

[hunterracing]

What are affects of say goin from 16 175 lr to a 20 inch 175 I know the spring will compress the same but overall dynamically would it increase more drive bein taller?

[a25rjr]

Slightly. A loaded spring will make more traction than an unloaded one. Plus it will stay more consistent as it stays centered on the spring seat.

[hunterracing]

But if it's same rate would it be loaded more if it's taller or apply more pressure I understand putting same weight on each spring should compress same but is there another variable there

[Matt49]

Assuming you end up with the same static ride height, spring length does NOT matter unless you are coil-binding. That should never be an issue on the left rear. There is nothing to be gained or lost by changing LR spring length unless you want to talk about weight.

[hunterracing]

So would goin from 175 16 to say 125 or 150 20 inch have more dynamics drive bcs it bein preloaded so much more to get static ride height back

[JustAddDirt]

you can put an 11" 175 on there and you would see no difference.
as Matt49 says, as long as it is not coil binding.

I myself prefer the shortest spring I can get. less area for deformation, or bow in the spring leads to a smoother coil over, or coil over eliminator movement.
plus less coils less weight.

[hunterracing]

Kinda what I figured but I wanted see others opinions on this deal

[a25rjr]

The same rate spring only longer will not be any different.

Mr. Link and Mr. Bush will differ with you. Notice I said slightly.

[hunterracing]

Then what bout the really soft lr spring like 125 to 150 would that take some drive away bein softer or gain alittle bcs it's loaded so much static then still pushing as car lift dynamically

[let-r-eat]

SCD,

You saying Mark Bush is a dummy? Yeah right....

Did you read what you typed?

What are your qualifications? 6th place at Boone? A couple street stock wins? WOO wins? LUcas OIl? Nascar? Hooters Tour? NE Mods? SW Mods? ARCA? What are they?

[MasterSbilt_Racer]

If your ride height is the same and your spring rate is the same, a longer spring gains you nothing. It doesn't matter who you think said it. They are flat out wrong, or you misunderstood what was said.

[Matt49]

Mark Bush has forgotten more about vehicle dynamics than most of us will ever know. But mostly, he is very good at explaining things in a way that people can understand but without leaving out the technical details. That's a rare quality.

Spring length doesn't matter unless you start operating outside of Hook's Law. That is a fact and that is the end of the discussion about spring length.

The reason a softer LR creates more initial forward bite has nothing to do with LOAD and everything to do with what happens when the spring UNLOADS and the resulting change in left side bar angles.
If you have 800 pounds on a 200 pound spring, at ride height, that spring is compressed 4 inches. If you transfer 400 pounds OFF of that spring, it unloads 2 inches. Do the same thing with a 100 pound spring and it unloads twice the distance which increases bar angle. Obviously we limit travel with a chain but the speed at which we get to that point is dependent on the spring rate. Softer will travel a greater distance given the same amount of unloading.

[hunterracing]

But he has also said the stiffer springs gets the weight so wouldn't that apply on lr to get more drive instead of goin softer and stuff

[Matt49]

But he has also said the stiffer springs gets the weight so wouldn't that apply on lr to get more drive instead of goin softer and stuff

That rule goes somewhat out the window with LR spring behind setups.
It also goes out the window on soft RF setups due to camber gain and roll center migration.

The old "stiff spring get the weight" stuff is great for street stocks but with extremely dynamic setups like we have today on late models and even mods, there is a lot more going on. The concept is still important to understand but it's just one layer of the onion that has to be peeled back.

[hunterracing]

So would you gain more dynamics from 16 inch 175 to. 150 16 inch spring? Jst throwing ideas around I've even seen a car with the left lower bar always against the housing not gonna mention names but he wins a lot of usmts stuff