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Denali_2017
08-02-2020, 02:59 PM
So first off I've been reading through this forum for quite some time and man there is so much good info on here!! So here goes my first post. I know there's alot of people who say you don't need a 20" LR spring but I need some info. While running a 20" 100lb spring with a chain limiter when you jack the car and have it on the limiter and that 20" spring is compressed to 16.5" is your droop load 3.5" x 100lbs = 350lbs of droop/pre load? And if so does this number effect what you dial in for left rear bite static on the scales?

MasterSbilt_Racer
08-02-2020, 06:19 PM
So first off I've been reading through this forum for quite some time and man there is so much good info on here!! So here goes my first post. I know there's alot of people who say you don't need a 20" LR spring but I need some info. While running a 20" 100lb spring with a chain limiter when you jack the car and have it on the limiter and that 20" spring is compressed to 16.5" is your droop load 3.5" x 100lbs = 350lbs of droop/pre load? And if so does this number effect what you dial in for left rear bite static on the scales?

Yes, your droop load is 350#. LR static bite on the scales doesn't mean much except maybe on a restart for a fraction of a second.

The only way to make both of those loads what you want is to adjust chain length or select the correct spring.

Denali_2017
08-02-2020, 06:34 PM
Thank you for responding so fast. I know it's a gm 4 arm triangulated mess back there but we have had great results with those numbers until recent when it's been hot and tracks slicks off. We had been lightning fast running around on the top but the last 2 nights it's been a bottom race track and we are lacking something down there. Been running 150lbs of static LR with that 350# load number. Do I need to open up the chain to let the car roll up more to run the bottom? Again appreciate your response

MasterSbilt_Racer
08-03-2020, 08:06 AM
Thank you for responding so fast. I know it's a gm 4 arm triangulated mess back there but we have had great results with those numbers until recent when it's been hot and tracks slicks off. We had been lightning fast running around on the top but the last 2 nights it's been a bottom race track and we are lacking something down there. Been running 150lbs of static LR with that 350# load number. Do I need to open up the chain to let the car roll up more to run the bottom? Again appreciate your response

Is the car sliding up the track on entry?

Denali_2017
08-03-2020, 08:13 AM
Car enters perfect wherever he wants to go. Says it's a little free getting in...center/off just doesent get up and go. Can hug the bottom all the way through no problem. Running a 850Rf with a tie down/Slow bleed and a 1000 bump spring. Soft spring is very new to us and we are still getting him use to it. Eventually want to start working down on the front spring rates as he gets comfortable

MasterSbilt_Racer
08-03-2020, 08:16 AM
Car enters perfect wherever he wants to go. Says it's a little free getting in...center/off just doesent get up and go. Can hug the bottom all the way through no problem. Running a 850Rf with a tie down/Slow bleed and a 1000 bump spring. Soft spring is very new to us and we are still getting him use to it. Eventually want to start working down on the front spring rates as he gets comfortable

More extended load will loosen off gas entry. More dynamic wedge will tighten exit. It sounds like you need more of that at the throttle application point. May need more bump spring engagement.

Longer chain could help from load standpoint, but will introduce more steer.

Denali_2017
08-03-2020, 08:21 AM
So if I have 4" of droop with that #350 lb load on a 100lb 20" spring I'd want to stiffen the spring to get a little less load so it's not so free off throttle? And increase static wedge for exit . And soften RF to keep it on the bump? Increasing chain will lower load, increasing rear steer but could combat that with lower arm angle or lead the RR a little

MasterSbilt_Racer
08-03-2020, 08:27 AM
So if I have 4" of droop with that #350 lb load on a 100lb 20" spring I'd want to stiffen the spring to get a little less load so it's not so free off throttle? And increase static wedge for exit . And soften RF to keep it on the bump?

Question #1 You need less load at the attitude of corner entry. A stiffer spring would do what you say, if the LR corner is up at that point. If a stiffer spring changes the attitude, that goes out the window.

Question #2 - I would soften main spring and raise the bump closer to engaging.

Denali_2017
08-03-2020, 08:29 AM
Ok these are some great things I can work on easily for this week. I appreciate you and your responses and will keep you posted on results

MasterSbilt_Racer
08-03-2020, 08:33 AM
Ok these are some great things I can work on easily for this week. I appreciate you and your responses and will keep you posted on results

Sounds good. The rf spring change may do everything you need. I'd do just that first. I had a metric car in the 90s that was very fast with a 1000# rf. No bump or anything. So you are still not that soft, IMO.

Denali_2017
08-03-2020, 08:38 AM
Yes everything we are working on has us headed to around 700 range. And I think with that bump spring we need to keep it buried longer so as I get him more comfortable and I get more understanding of it the better it will get. We aren't off much

racer-15
08-10-2020, 03:13 PM
Make sure the 20 inch spring isn't bowed. From what ive seen it works good for a few nights then spring bowes and car totally changes.

racetech
09-12-2020, 08:45 PM
We have been out of the SS game for a few years and just got back into it this year. I remember our old car was flat with fairly stock rear trailing arm angles, We were fastest with an 1100 RF spring. Wow have things changed. We are running absurd rear bar angles on the lowers, and 80 lb 20 inch lr spring, an 800 RF with a bump, and we are still figuring things out. We had a 700 RF earlier this year and I cant say it was bad. Still working on the sticking the RR on entry it hasnt been good. We just had a practice session and upped the LF spring from 950 to 1100 and it was better, but it didnt get really good till we shimmed LF bump till we had about 3/8 inch of travel, it plants that RR now lol

JustAddDirt
09-25-2020, 03:51 PM
triangulated 4 link on the GM cars do not work like a late models parallel 4 link.
i see people trying the soft RF spring deal, and they struggle.
the GM rear suspension binds up pretty bad, it may help if you have mono-balls in all the joints.
you are unloading and holding weight off the left rear corner of the car.
I just dont get it? maybe i am wrong.