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racefastnow
09-18-2015, 01:40 PM
What's the formula to figure out stack spring ratio. Also what would recommendations for a LR setup. Run a 200 now. Does the stack work better to have preload at full droop. Right now we have no preload and lacking drive, traction. Looking to maybe try the stack with a little preload.

Also, what opinions on clamping the front LR shock. Taking it off the birdcage?? Any help would appreciate it

Wheelman33
09-18-2015, 02:36 PM
Formula is AxB/A+B. Throw a 4 inch 400# spring on top of that 200 and you'll have a 133# spring. Having a hard time understanding how you have no preload with a 200 though.

Punisher88
09-18-2015, 02:55 PM
Go around your car at all four corners lowering the bite then put it back in with your lr spring. One round out of the rf one round in lf 2 rounds in rr and 2 rounds out of lr will lower it around 30 to 40 lbs. Then add it back with the lr will probably take 6 to 8 rounds. Depending on the shock threads. I run 80 lbs with 3/8 preload in lr

TALON75
09-18-2015, 02:57 PM
He's saying that when his lr is in droop it is off the spring, pretty common, hence the take up spring. I would like to tell you the right combo to run but right now I'm not sure what it is!!lol the 133 seems pretty soft and can make the lr "springy", it really jumps to the bars on the gas and drops just as fast.

25drtrkr
09-18-2015, 06:00 PM
He's saying that when his lr is in droop it is off the spring, pretty common, hence the take up spring. I would like to tell you the right combo to run but right now I'm not sure what it is!!lol the 133 seems pretty soft and can make the lr "springy", it really jumps to the bars on the gas and drops just as fast.

I always favored using the locknut set at ride height for that same reason.

racefastnow
09-18-2015, 07:32 PM
With the spring unloaded it measures 14 1/8. On full droop nut is in the spring with very little pressure. At ride height the spring is 11 1/2. We were initially thinking when the car is on chain on bars, maybe it needs preload to load the LR more. Than thought the stacked stuff would be better suited for that type of setup

Brian Gray
09-18-2015, 07:44 PM
Best info your gonna get is what talon just told you. If your looking for drive your not gonna find it by lowering the spring rate.

With current suspension designs you're rate is what you end up with on the bars. The lr spring in my opinion only influences transfer amounts and nothing more after you are on the bars.

racefastnow
09-18-2015, 07:48 PM
Thanks, anyone run the LR front shock locked to the rear end. And only the back shock on the bird cage? If so, any recommendations for doing so. Can you run same shock valving and spring

Matt49
09-19-2015, 10:43 AM
Thanks, anyone run the LR front shock locked to the rear end. And only the back shock on the bird cage? If so, any recommendations for doing so. Can you run same shock valving and spring

This will decrease the motion ratio of the shock. So you will need more dampening to get the same feel.

racefastnow
09-19-2015, 02:57 PM
Can you do this by adding gas pressure to the rear shock

Matt49
09-19-2015, 10:25 PM
Adding gas pressure to the rear shock will make rebound feel softer and compression feel stiffer. Gas pressure creates rod pressure which also increases effective spring rate. Really high gas pressure is common in LR shocks.
These are generalizations...some other people that know way more about shocks can elaborate but most of them aren't going to share too much free information. Can't say I blame them, but that is the reality of the shock game these days.