LR Stack Spring

[strong08]

I bought a set of shocks from Rocket and I had them set up the LR with a stacked spring set up. It was suppose to be set up with 200 pounds of extended load. When I have the car up on stands and the rear end is hanging at full extension with the chain tight, the top spring and bottom spring doesnt touch. So my question is people setting the 200 pounds of load when the rear end of the car is full dropped out or is it set when the shock is compressed at a lesser length.

[Jking24]

I bought a set of shocks from Rocket and I had them set up the LR with a stacked spring set up. It was suppose to be set up with 200 pounds of extended load. When I have the car up on stands and the rear end is hanging at full extension with the chain tight, the top spring and bottom spring doesnt touch. So my question is people setting the 200 pounds of load when the rear end of the car is full dropped out or is it set when the shock is compressed at a lesser length.It's generally set at 4" from ride height. Is this a xr-1 or blue Grey car ?

[TheJet-09]

I'm not a Rocket guy, but along the lines of Jking24, I'd check what the extended center-to-center is supposed to be. Things like where the RR is at (such as when you have it on jack stands, is the RR supposed to be at ride height?) and the LR link location/s can affect the LR droop center-to-center.

[grt74]

depends on the springs (how soft) i could believe that with the right springs, and check your measurement on the lr, some cars let out a ton (too much) on the limiter, it wasn't to long ago they found out too much is bad too, us racers go too far on everything from time to time, thats why you'll here a guy say "we went back to standard" sometimes

[strong08]

its on a XR 1. I have a 90/200. The rear is fully extented. My measurement between axle tube a bottom of frame is 18 7/8 inch. which is standard. I looked at the recommend c toc its 18 5/8 icns which I am not at I am more around the 20 1/2 inch with car on the ground with me in it. I cant go any lower the top nut on the shoch is up far as it will go. At rocket he told me he set the extented load at 22 5/8 inchs but the spring was a mile from touching. After reading the prevoius statement a industry standard of 4 inchs the 22 5/8 makes sense. Note: I am running a 604 in the car. And it is tight on entrance and really tight in the center espcecially if I run at Tazewell Speedway. If I run at Lake Cumberland same thing except leaving the corner exspecially 4 it spinns the RR and I am side was.

[cjsracing]

22 5/8 seems short for full drop. My MB Custom c to c at full extension is 24 1/2 to 25" (depending on my bar location)

[MasterSbilt_Racer]

22 5/8 seems short for full drop. My MB Custom c to c at full extension is 24 1/2 to 25" (depending on my bar location)

It's not full drop, but it's where Rocket says to check. Why? Beats me...

[billetbirdcage]

its on a XR 1. I have a 90/200. The rear is fully extented. My measurement between axle tube a bottom of frame is 18 7/8 inch. which is standard. I looked at the recommend c toc its 18 5/8 icns which I am not at I am more around the 20 1/2 inch with car on the ground with me in it. I cant go any lower the top nut on the shoch is up far as it will go. At rocket he told me he set the extented load at 22 5/8 inchs but the spring was a mile from touching. After reading the prevoius statement a industry standard of 4 inchs the 22 5/8 makes sense. Note: I am running a 604 in the car. And it is tight on entrance and really tight in the center espcecially if I run at Tazewell Speedway. If I run at Lake Cumberland same thing except leaving the corner exspecially 4 it spinns the RR and I am side was.

Your 20 1/2" ride height on the ground is pretty typical if your using rockets load numbers

[cjsracing]

It's not full drop, but it's where Rocket says to check. Why? Beats me...

hmmm interesting

[MasterSbilt_Racer]

hmmm interesting

A lot of places, a good driver lives from full extension to down 1". So, doesn't make sense to me.

[strong08]

i am hearing people is getting much as 300 lbs of extended load on this cars. Is that because its being set with such a compressed number instead of being set with the shock being full extended.

[cjsracing]

i am hearing people is getting much as 300 lbs of extended load on this cars. Is that because its being set with such a compressed number instead of being set with the shock being full extended.

To compensate for really soft RF's. Running 175 RF you need to have some more extended load to make up for that RF not pushing back on the LR.

A friend who has a Rocket just got a new set up shocks smashed and ready to put on - 175 RF and 300lbs of extended load on the LR.

[7uptruckracer]

What kinda bump are they using with that RF?


To compensate for really soft RF's. Running 175 RF you need to have some more extended load to make up for that RF not pushing back on the LR.

A friend who has a Rocket just got a new set up shocks smashed and ready to put on - 175 RF and 300lbs of extended load on the LR.

[strong08]

550 Bump spring with a 200 pound 14 inch spring. Something I have been confused on is at point to switch back to a traditional bump stop. Is that when I switch to 275 spring or when. Rocket did tell me when I run springs for Volunteer or Tazewell to go back to a Tradtional bump stop. So far I have been using the bump spring at both cant tell much difference in feel compared to a bump stop. Grated I used the bump stop on a Blue gray and not a XR1. I plan on trying a traditional bump at Tazewell this week.

[7uptruckracer]

That seems pretty soft on the bump spring…weird

550 Bump spring with a 200 pound 14 inch spring. Something I have been confused on is at point to switch back to a traditional bump stop. Is that when I switch to 275 spring or when. Rocket did tell me when I run springs for Volunteer or Tazewell to go back to a Tradtional bump stop. So far I have been using the bump spring at both cant tell much difference in feel compared to a bump stop. Grated I used the bump stop on a Blue gray and not a XR1. I plan on trying a traditional bump at Tazewell this week.

[MasterSbilt_Racer]

^^has to be coil bound.

Now, that probably occurs at 2100-2200 # depending on his initial ride load and gap, so maybe it isn't too bad.

[TRocket8]

On the rocket set-up set up sheet, if you run a 200 with a 550 bump spring, it says you need an internal bump stop in the shock. I never ran that setup so I am not sure.

[fastford]

we figured out pretty quick that on a rough track , the bump spring or even the 2 stage set up was better and a smooth track the rubber stop was better , we never went that soft on the bump spring though , we also migrated to the long soft lfr spring over the stacked , we like the swift tornado spring the best...jmo...

[Jking24]

On the rocket set-up set up sheet, if you run a 200 with a 550 bump spring, it says you need an internal bump stop in the shock. I never ran that setup so I am not sure.I believe they are referring to a.500" spacer inside the bump spring to keep it from coil binding

[latemodel99]

its on a XR 1. I have a 90/200. .

What brand/length of springs do you run? Been looking for about a 100lb short spring (6in) but not able find anything.

[MasterSbilt_Racer]

What brand/length of springs do you run? Been looking for about a 100lb short spring (6in) but not able find anything.

I think PAC made that spring, if you can find someone who bought up their inventory.

Swift makes it in the barrel type.

[7uptruckracer]

8” 100 12” 200 use the unloaded on the smasher to assemble it. 6” will coilbind

[MasterSbilt_Racer]

Even at 8", swift isn't supposed to be loaded to 600#. I assume the poster has something different than cookie-cutter in mind.

[7uptruckracer]

I think last one I did was 645 and it was a sheet of paper from starting to touch coils lol. But I never got the load down to raise deck more before the car got put away for covid


Even at 8", swift isn't supposed to be loaded to 600#. I assume the poster has something different than cookie-cutter in mind.

[Austin34471]

Easy equation for what spring is needed for your desired "extended load"

Spring rate = ((Ride height load) - (Desired extended load)) / (Extended center to center) - (Ride height Center to center)

Example: I want 100# of extended load, my ride height load is 600#. My Ride height center to center is 15", my extended center to center is 20"

(600# - 100#) / (20" - 15") = 100 lb/in spring

[Jking24]

Easy equation for what spring is needed for your desired "extended load"Spring rate = ((Ride height load) - (Desired extended load)) / (Extended center to center) - (Ride height Center to center)Example: I want 100# of extended load, my ride height load is 600#. My Ride height center to center is 15", my extended center to center is 20"(600# - 100#) / (20" - 15") = 100 lb/in springGood info but worth mentioning this only works for non lockout setups

[Austin34471]

Good info but worth mentioning this only works for non lockout setups
That equation gets a little tougher but is pretty easy to do on a spreadsheet. I raced for a long time with no spring smasher, just microsoft Excel on my phone.

[MasterSbilt_Racer]

That equation gets a little tougher but is pretty easy to do on a spreadsheet. I raced for a long time with no spring smasher, just microsoft Excel on my phone.

I only got a smasher to deal with bumpstops. I hear you.

[Modified18]

Is there a way to figure out using spring rubbers in Excel or is that something you absolutely need a spring smasher for?

[MasterSbilt_Racer]

Is there a way to figure out using spring rubbers in Excel or is that something you absolutely need a spring smasher for?

That's another one where you need to check it, to really know. Those were invented for a hail Mary adjustment, it's funny how they are considered std equipment now.

[Modified18]

Thank you good to know. I'm new to all the coil stuff racing a big block modified and we were on torsion bars for years. Been trying to use 4m as a way to catch up on things. Spring rubbers seem to be the main thing people are using on them currently.

[skippydoo10]

Thank you good to know. I'm new to all the coil stuff racing a big block modified and we were on torsion bars for years. Been trying to use 4m as a way to catch up on things. Spring rubbers seem to be the main thing people are using on them currently.
I'm new to coils too, 602 crate Teo car at Orange County Middletown . Where do you run?