quick coilover spring rate question

[Vanimal]

i originally had 12" 225/275's in my front at about 50% droop, however i wanted to change some things and bring it closer to 60%. this involved changing my springrate. i had a spare set of 14" 150lb coils that i tried swapping out my 12" 225lb coils for.
14" 150lb over 12" 375... will this have any adverse effects on handling vs like a 12" 175/275? this is more of a rock crawler but i want it to handle some minor go fast. in my mind, it almost seems like the 150/375 would be better for that since i'll still have the stiffer main spring for when it hits the stop ring. just want to make sure i'm not missing something.

 

[desertjr]

I would love to have coilovers on my rig with a 3" lift. What would I need 10" coil overs? Its not a go fast rig but gets there some times, mainly camping/minor crawling/wheeling.

 

[vetteboy]

That's a whopper of a step-up rate...you'll feel that for sure. It can 'work' depending on your valving but on a well-tuned suspension it's rare to see more than 100 lbs difference in the top and bottom springs.

How much preload do you have on 'em?

 

[Vanimal]

not very much

 

[Vanimal]

took it out today, it actually wasnt bad. didnt notice it offroad, other than a little added plushness which i needed anyways.
i need bumpstops now, i managed to bottom it out once.

 

[PahlMc]

If I did my math right your new main rate is 107 and when you hit your spring stops that rate jumps to the lower spring rate (I assume you have the 375 on the bottom). That is a big jump in rates from my experience. Personally I never actually used the dual rate even on my race car. But if you liked it out in the fast stuff, no worries!

Now you said you did bottom out. Since you just changed your spring rate, I recommend you re-valve your shocks if they are a little too soft. Bump stops are never a bad thing but spend some time valving those coilovers.

 

[Vanimal]

yep, 107. the dual rate slider hits the stop rings in the last few inches of travel in the front. the valving is most likely off, i got the shocks from a guy who had them valved for the rear of a rear engine sand rail. however, it isnt horrible. the plan was to get both front and rear coilovers revalved when i finally settle on a spring rate.

 

[vetteboy]

Right now you're using the springs to manage the big hits; that's not what you want to do as they don't absorb anything and you're left with slow rebound in order to keep it from flying all over the place.

Ideally you want to use the springs as a compliant means of supporting the vehicle weight; use the shocks to absorb, well, shock.

What diameter shock and what do you figure the sprung corner weights to be up front?

 

[Vanimal]

running 2.0's. my corner weight is about 770lbs in the front, 660 in the rear.