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cnorman
09-17-2011, 10:25 PM
I Have Heard Alot Of People Talking About Running Stacked Spring. How Do You Callculate The Spring Rate And Is The LR The Only Place You Can Run It On? What About Everywhere Else? What Are The Advatages Of Running Stacked Springs? How Does It Affect The Car Verses Standar Springs?

Dirt2727
09-17-2011, 11:37 PM
http://www.jimmyjudd.com/jimmy/spring_rate_cal.htm

Egoracing
09-18-2011, 08:12 AM
(Spring X spring) / (Spring + Spring)= stack rate
200 X 400 / 200 + 400 = stack rate
80000 / 600 = 133.3333.....

cnorman
09-18-2011, 09:51 AM
Thanks For That .... But What Are The Advantages Of It? Does That Mean If You Run A 800/600 combo On The RF It Will Travel Like A Hard Spring But Act Like A Soft One?

Egoracing
09-18-2011, 10:13 AM
Thanks For That .... But What Are The Advantages Of It? Does That Mean If You Run A 800/600 combo On The RF It Will Travel Like A Hard Spring But Act Like A Soft One?

The regular stack on the LR allows you to run a spring rate that would compress and bend if you ran a regular setup. A 133 LR would not last but the stack adds more metal to the spring which allows it to carry the weight without fatigue.

grasshopper
09-23-2011, 07:43 PM
Running a stacked spring on the right front you get in the corner on the bottom spring. Get off the corner on the top spring. The stacked springs lets you get in the corner on a soft spring and off the corner on a stiff spring that loads the LF rear and gives you drive off. some one tell me if im wrong.

Dirt Man
09-23-2011, 08:12 PM
Running a stacked spring on the right front you get in the corner on the bottom spring. Get off the corner on the top spring. The stacked springs lets you get in the corner on a soft spring and off the corner on a stiff spring that loads the LF rear and gives you drive off. some one tell me if im wrong.

Your wrong!

Egoracing
09-23-2011, 09:02 PM
The only time it will react as 2 springs is if you are running a limiter and lock nut setup. A dual stack is just a better way to run a softer spring.

Matt49
09-24-2011, 05:49 AM
Like clockwork, this topic comes up about once a month and invariably 15 people chime in and don't know what the difference is (or that there even is a difference) between a "stacked spring" and "dual stage" setup.
Stacked spring is just that: two springs one on top of the other. And it won't run or behave any different than the a spring of the spring rate determined by the formula that Egoracing posted UNLESS one of the springs coil binds and you should never do that intentionally (or on accident for that matter). This is commonly used on the LR where a soft spring rate is desired but can't be achieved with a single, long spring due to bowing. Contrary to what a lot of people think because they read it in a book somewhere, softer LR makes for tighter corner exit.
Dual stage involves use of a slider and lock nut so that one spring is taken out of the equation after a certain amount of travel (determined by location of the lock nut). This is commonly used on the RF to get the car to roll over on entry using the soft combined spring rate and then stand on the stiffer spring to generate LR dynamic bite on exit. It's an alternative to the bump stop setup that is loved and hated by so many.

Ruhlman Race Cars
09-29-2011, 10:27 AM
We offer dual rate spring set-ups as well as bump stop and bump limiter combinations for late models and modifieds.

Give us a call and we can get your shock and spring program on track.

bwels25
09-29-2011, 11:33 AM
We offer dual rate spring set-ups as well as bump stop and bump limiter combinations for late models and modifieds.

Give us a call and we can get your shock and spring program on track.

I can tell you for a fact this does work and Brian knows what He is talking about! The best our car has ever been. thanks Brian

dualdj1
09-29-2011, 04:03 PM
Just out of curiosity... on the spring rate calculations, does spring length make a difference? As in, do both springs have to be the same length, or can you use different spring lengths? I wouldn't think it would matter, but didn't know for sure.

Egoracing
09-29-2011, 05:32 PM
Just out of curiosity... on the spring rate calculations, does spring length make a difference? As in, do both springs have to be the same length, or can you use different spring lengths? I wouldn't think it would matter, but didn't know for sure.

No, The only thing that matters is if you can get the nut on the shock with both springs on.

CHUMBA
09-29-2011, 07:38 PM
does anyone make a spring compresser? need to compress both about 2" to get everything together.

Egoracing
09-29-2011, 08:26 PM
does anyone make a spring compresser? need to compress both about 2" to get everything together.

Typically it is a 10 inch spring and a 4 inch spring in the stack and you do not need to compress it. If it is loaded that much you will damage the shock without the cars weight on it.

CHUMBA
09-30-2011, 06:43 PM
I have tried that the 4" is going to coilbind before i get the travel needed, iam using the 5" afco spring now and its close to coilbind, I want to go softer up there, thats why I want to run 6 or 7" spring. running integra shocks nut goes on first then spring then devider then next spring then then cone, thats the part I need about 1 1/2 to 2" of spring compress to get on. the bottom spring is 8". any thoughts anyone???

giffordracing
10-01-2011, 01:46 PM
8" bottom spring...4" top...12 inches total...

jedclampit
10-01-2011, 11:49 PM
I have tried that the 4" is going to coilbind before i get the travel needed, iam using the 5" afco spring now and its close to coilbind, I want to go softer up there, thats why I want to run 6 or 7" spring. running integra shocks nut goes on first then spring then devider then next spring then then cone, thats the part I need about 1 1/2 to 2" of spring compress to get on. the bottom spring is 8". any thoughts anyone???

What rate are you trying to produce?
What lengths/rates are you using?
Your short spring is probably too soft.

CHUMBA
10-02-2011, 05:04 PM
What rate are most people running? (the combinded of the two springed) 200 to 250 or 250 to 300 or more or less? Iam in the 250 to 300 range. Thanks!

jedclampit
10-02-2011, 08:26 PM
If you are after a 200+ #/ inch spring , I see no reason to stack.
If less than 200, then there is a reason to.
The example above to get a 133# / inch should suit you well.
4" 400 and 8" inch 200=133#/inch 12 " spring.

CHUMBA
10-02-2011, 09:10 PM
jedclampit: this is for a right front app. were thinking 300 top and 700 bottom with stop nut.

MasterSbilt_Racer
10-03-2011, 01:22 PM
jedclampit: this is for a right front app. were thinking 300 top and 700 bottom with stop nut.

That 300 is your problem. You are probably going to need a 6 or 7 inch spring. Good luck finding one.

CHUMBA
10-03-2011, 05:03 PM
yes i know thats why I was looking for spring compresser, and also wondering, what two springs most were useing? and if Iam way off on what Iam wanting to try. Thanks for replys CHUMBA.

CHUMBA
10-03-2011, 07:21 PM
I have run 400 on top of 400 and it was loose coming of thats why I thought about going stifer on bottom, the tracks I run on bad slick!! I have played with adj on stop nut, but still loose off.

MasterSbilt_Racer
10-03-2011, 09:10 PM
I have run 400 on top of 400 and it was loose coming of thats why I thought about going stifer on bottom, the tracks I run on bad slick!! I have played with adj on stop nut, but still loose off.

Well then just stiffen the bottom.

CHUMBA
10-03-2011, 11:14 PM
We have but the more I stiffin the bottom the closer the top 400 5" spring is getting to coil bind, if I go to a 6" long spring I cant get the bottom cone on. Thats why I was asking about spring compresser. anyone know of anyone making one? or a way to get the spring compressed to get cone on? Thanks again for all replys.

grt74
10-04-2011, 06:51 AM
chumba,use two 7in springs,you may have to work a little to get them on but they will go on by hand,we use hypercoil springs on ohlins shocks or a 7 and a 5 or 6 and a 4in spring i would not worry about the coil bind because it should hit the lock nut before coil bind if adjusted right but you can always check it on a shock/spring rater before putting it on the car

CHUMBA
10-06-2011, 05:29 PM
grt74 you got PM

giffordracing
10-28-2011, 07:24 AM
600 4 inch top
500 8 inch bottom

CHUMBA
10-29-2011, 12:57 AM
Please explane how this combo would work?? I dont get the 600 on top of the 500. pm me if you dont want the whole world knowing. thanks chumba.

Sprint76
10-29-2011, 09:02 AM
Chumba, clear your PMs.

mackwrench
10-29-2011, 11:15 AM
STACKED SPRING RATES

400 / 175 = 122

400 / 200 = 133

400 / 225 = 144

400 / 250 = 154

400 / 275 = 163

400 / 300 = 171

400 / 325 = 179

400 / 375 = 194

400 / 400 = 200


Formula:

Top spring Top spring
X (divided by) + = Total Spring Rate
Bottom spring Bottom spring

Example:

400 X 225 = 90,000

400 + 225 = 625

90,000 divided by 625 = 144

CHUMBA
10-29-2011, 12:24 PM
PMs cleared, I think

rcmaster
11-01-2011, 10:36 PM
PMs cleared, I think

you guys have alot to learn, hypercoil will get you lentgh you need, get you a checker and check stack rates with different nut settings,you will be shocked, and when you run it make sure you have a travel indicator on outside of shock.

CHUMBA
11-02-2011, 06:37 PM
Teach us old wise one! thats why Iam asking questions on here trying to learn, dont have budget to travel 4 hours rent track and just try things, I have called chassie builder, he dosent run it. and wont give advise on it! PM me if your are interested in helping. CHUMBA

rcmaster
11-05-2011, 10:13 PM
not trying to be smart,it just takes testing, every driver is different,how much rebound you run in right front makes huge difference, most people will try it and run it if it works that night if not they wont adjust it just take it off.one last thing figure out how much rf travel your car gets when its at its best then make sure your stack gets same travel then adjust to liking--------- its really difficult to explain all the different adjustments.

CHUMBA
11-06-2011, 04:52 PM
Not calling you a smart ass!!! Just trying to get as much info as I can. we have ran it our last three races, and are going to continue to work with it, I think we have figured out we are running too much gap, thats the only direction we have been adj, when we start raceing again we are going to go less gap, but that will be in april 2012. so Iam just trying to learn more about the complete set up so we can be close. thank you for info, and again sorry for implying you were a smart ass, not my intention!!
Chumba.

BDR40
11-18-2011, 10:19 PM
A lot of guys run around a 400-600# 4 inch spring with anywhere from a 350-450# 8 inch spring on the dual stage stuff. Brian @ Integra recommended that we start with a 600/400# to start out.

CHUMBA
11-19-2011, 12:33 AM
thats funny 2 years ago I ask him about doul stage stack spring on right front and he said he knew nothing about it. that was after I spent around $1000.00 getting shocks repaired & revalved.

Ltemodel
11-20-2011, 01:26 PM
We start at a 600# top and 400# bottom and put 3/8" to 5/8" gap in the lock out ring at ride height. The best way to figure gap, if you can't test, is to record your RF dynamic ride height with your slick RF set up in. Usually you will soften RF for slick. Record your compression travel on the RF.
Record your shock eye to eye measurement at ride height.
Take your spring and shock off the car and put it into a spring rater and compress it to ride height and then dynamic ride height and record those two load readings.
This will give you the load the spring is supporting at its maximum in the corner and load at ride height.
Then stack up your springs with the lock out and adjust them so that your spring eye to eye measurement and your load at ride height come back to the original measurements.
Then you can compress it and start playing around with the dynamic side.
If you want to raise the RF ride height in the middle of the corner, take gap out of your lock out adjuster.
If you want more travel on to the RF before it stops, put a larger gap into your RF setup.
This set up is not a cure all deal. It is good if you know how to work with it. Experiment and have fun.

Kevin