The Mustang Forum for Track Enthusiasts

Track Mustangs Online was built specifically for those who track their Mustangs!

Register Log in

CorteX JRi Double Adjustable Front & Rear Damper Adjustment Settings

twistedneck

TMO Race
Messages
317
Reaction score
30
Location
Dearborn, MI
Everyone,

I am really impressed with the build quality of my Cortex / JRi coilover set.

Front two way adjustable, rear one way. I know these are digressive dampers after confirming that with Filip and i do understand that part.. Filip also sent me a JRi adjustment guide but i still have some questions.

Seems its not so simple as 'compression and rebound' like i thought.

The main top knob is called the 'Low-Speed Adjuster' and the small hex nut under that is the "High-Speed Adjuster / REBOUND"

the low speed main knob has 30 clicks, if you crank it down i.e. std right hand thread you get full stiff.. it comes pre-set at the half way point -15 clicks.

The high speed rebound adjuster needs to be tracked via the number of flats in the nut that you sweep through.. back that nut out all the way and its full soft, + 14 flats = full stiff.

I need help understanding these..

is the low speed adjuster affecting compression and rebound or just compression? Is the high speed for rebound only? What do you normally run? is the factory adjustment a good place to start? i ask because the low speed comes in pre-adjusted half way, and the high speed rebound is only 5 flats out of 14.

Help appreciated, thanks,

Jeff Check.
 

JScheier

Too Hot for the Boss!
Messages
790
Reaction score
3
Location
Denver, CO
Re: Help me understand my new coilover adjustments (JRI - cortex)

Not Cortex, but a great article by my buddy Brian at HVT.
 

2013dibgt

TMO Advanced
Messages
119
Reaction score
5
Location
PA
Re: Help me understand my new coilover adjustments (JRI - cortex)

I have a different setup then the OP but still a package from Cortex and FWIW, I spent this past summer toying around with various shock damping settings and after all was said and done I only ended up a click or two less then the default settings that the dampers arrived at as my ideal setting.

Assuming the same tuning was done to yours its probably a safe bet to think you won't need to stray too far from the settings you received them. In other words, there is probably little need to reinvent the wheel like I did only to arrive at a setting that isn't far from the defaults.
 

SDS

TMO Intermediate
Messages
98
Reaction score
13
Location
East Bay
Re: Help me understand my new coilover adjustments (JRI - cortex)

I dropped the Boss at Cortex today installation for the same setup you have - JRI DA strut/ SA back. I'll ask about adjustments when I pick it up Tuesday if we don't have an answer by then.

Steve
 

cortexracing

TMO Intermediate
Supporting Vendor
Messages
21
Reaction score
22
Re: Help me understand my new coilover adjustments (JRI - cortex)

Here is some guidance on setting up the JRi shocks.

The JRi low speed adjuster affects both compression and rebound but in a strategic way. The rebound adjuster (high speed adjuster) only affects rebound.

CorteX recommends the following setting listed below for the double adjustable shocks and struts. The setting can vary depending on spring rates, tires used, and driver preferences.

Front Struts

Baseline (Should be as-shipped)
+5 High speed (lower adjuster - "sweeps")
-15 Low speed (Top adjuster - "clicks")

Strut Softer Setting
+2 High speed (lower adjuster "sweeps")
-6 Low speed (Top adjuster "clicks")


Rear Shocks

Baseline (Should be as-shipped)
+12 High speed (lower adjuster - High Speed "sweeps")
-6 Low speed (Adjuster at the end of the shaft - Low Speed "clicks")

Shock Softer Setting
+4 High speed (Second adjuster "sweeps")
-3 Low speed (Adjuster at the end of the shaft - "clicks")
 

SDS

TMO Intermediate
Messages
98
Reaction score
13
Location
East Bay
Re: Help me understand my new coilover adjustments (JRI - cortex)

I picked my car up from Cortex with the DA-SA JRI/watts setup this week. Due to the rainy weather, I hadn't been able to play with it until today. The ride height and camber/ caster ride setup was done primarily for track use.

First impressions are that the stock JRI settings are plenty stiff, the rear end seems very planted. The car seems to be on rails, and the turn-in is instant. I also drove a fiends 13 Boss today with Koni's but no watts link for comparison. The Koni setup was closer to the stock, not as stiff as the JRIs but this is probably due to softer damper settings.

Cortex was great to deal with in every aspect, quality parts, installation and setup. I have been on the fence on suspension changes and am glad I waited until i could afford this level of quality.

I'm really looking forward to getting onto the track with this upgraded suspension and I haven't stopped smiling after today's little test drive

Steve
 

twistedneck

TMO Race
Messages
317
Reaction score
30
Location
Dearborn, MI
Re: Help me understand my new coilover adjustments (JRI - cortex)

CorteX Racing said:
Here is some guidance on setting up the JRi shocks.

The JRi low speed adjuster affects both compression and rebound but in a strategic way. The rebound adjuster (high speed adjuster) only affects rebound.

CorteX recommends the following setting listed below for the double adjustable shocks and struts. The setting can vary depending on spring rates, tires used, and driver preferences.

Front Struts

Baseline (Should be as-shipped)
+5 High speed (lower adjuster - "sweeps")
-15 Low speed (Top adjuster - "clicks")

Strut Softer Setting
+2 High speed (lower adjuster "sweeps")
-6 Low speed (Top adjuster "clicks")


Rear Shocks

Baseline (Should be as-shipped)
+12 High speed (lower adjuster - High Speed "sweeps")
-6 Low speed (Adjuster at the end of the shaft - Low Speed "clicks")

Shock Softer Setting
+4 High speed (Second adjuster "sweeps")
-3 Low speed (Adjuster at the end of the shaft - "clicks")
Thanks for clearing that one up.

Can you post the same information on the SA rear JRI setup?

Thanks
 

Grant 302

OPM Spent: $665,833
Moderator
Messages
7,322
Reaction score
2,086
Location
In the OC
Re: Help me understand my new coilover adjustments (JRI - cortex)

CorteX Racing said:
Rear Shocks

Baseline (Should be as-shipped)
+12 High speed (lower adjuster - High Speed "sweeps")
-6 Low speed (Adjuster at the end of the shaft - Low Speed "clicks")

Shock Softer Setting
+4 High speed (Second adjuster "sweeps")
-3 Low speed (Adjuster at the end of the shaft - "clicks")
http://cortexracing.com/wp-content/uploads/Instructions/JRi_DB_Adj%20Shock.pdf

Is this .PDF current? It says that the low speed adjuster has 25 clicks, and mine seem to turn well past that (40) without any sign of resistance...and that's both sides. Also seem to be a bit stiff for the street even at -25. Currently have the rear set at +10, -25.

Any suggestions?
 

ilesjohn

TMO Intermediate
Messages
68
Reaction score
0
Re: Help me understand my new coilover adjustments (JRi - CorteX)

Grant try +8, and -14, & they do turn more than indicated but i don't think it does further adjustment. Make sure to turn them all the way to the reference point and start from there
 

Grant 302

OPM Spent: $665,833
Moderator
Messages
7,322
Reaction score
2,086
Location
In the OC
Re: Help me understand my new coilover adjustments (JRi - CorteX)

ilesjohn said:
Grant try +8, and -14, & they do turn more than indicated but i don't think it does further adjustment. Make sure to turn them all the way to the reference point and start from there
That's close to one of the settings I tried on Friday. +8 and -15 or -16 and it felt like uncontrolled bouncing in the back. Initially started at +8 and -4 and kept clicking down to -20. Set it to -25 to roll to the track.
 

twistedneck

TMO Race
Messages
317
Reaction score
30
Location
Dearborn, MI
Re: Help me understand my new coilover adjustments (JRi - CorteX)

Grant 302 said:
That's close to one of the settings I tried on Friday. +8 and -15 or -16 and it felt like uncontrolled bouncing in the back. Initially started at +8 and -4 and kept clicking down to -20. Set it to -25 to roll to the track.
Uncontrolled boucing = not good! i assume you have the 300 lbs / in rear springs?

I have the SA rear setup - i assume i only have the high speed rebound on the SA rear? so to deal with uncontrolled bouncing in the rear i would reduce the rebound damping by adjusting the 14 flats so that its +4 or so out of the 14 total, that way rebound is only 1/3 stiff?
 

Grant 302

OPM Spent: $665,833
Moderator
Messages
7,322
Reaction score
2,086
Location
In the OC
Re: Help me understand my new coilover adjustments (JRi - CorteX)

twistedneck said:
Uncontrolled boucing = not good! i assume you have the 300 lbs / in rear springs?

I have the SA rear setup - i assume i only have the high speed rebound on the SA rear? so to deal with uncontrolled bouncing in the rear i would reduce the rebound damping by adjusting the 14 flats so that its +4 or so out of the 14 total, that way rebound is only 1/3 stiff?
I'm assuming you have a low speed adjuster that clicks. Is that right? I don't think you should have the problem because you can't run your HS rebound too low. But that's just my guess. Do you have an SA data/instruction sheet?

I have 350 lb./in in the back and 550 up front.
 

twistedneck

TMO Race
Messages
317
Reaction score
30
Location
Dearborn, MI
Re: Help me understand my new coilover adjustments (JRi - CorteX)

Grant 302 said:
I'm assuming you have a low speed adjuster that clicks. Is that right? I don't think you should have the problem because you can't run your HS rebound too low. But that's just my guess. Do you have an SA data/instruction sheet?

I have 350 lb./in in the back and 550 up front.
the adjuster is on the bottom of the shock so i am assuming its the low speed / rebound. I didn't get a sheet from cortex on how the rear SA damper works. Anyone have a copy?
 

Grant 302

OPM Spent: $665,833
Moderator
Messages
7,322
Reaction score
2,086
Location
In the OC
Re: Help me understand my new coilover adjustments (JRi - CorteX)

This isn't a sheet from CorteX or the Mustang specific setup:


Like this:


How many clicks do you have?
 

twistedneck

TMO Race
Messages
317
Reaction score
30
Location
Dearborn, MI
Re: Help me understand my new coilover adjustments (JRi - CorteX)

That looks exactly like my setup. when i get home i'll take a look at number of clicks. thanks!!

Ok I got home and took a look. I hve that exact same shock spring combo and adjuster. It has a total of 72 clicks. Its 22 clicks away from the full + (I assume that's 14 clicks more rebound high speed rebound damping than middle?)..
 

ilesjohn

TMO Intermediate
Messages
68
Reaction score
0
Re: Help me understand my new coilover adjustments (JRi - CorteX)

Grant 302 said:
That's close to one of the settings I tried on Friday. +8 and -15 or -16 and it felt like uncontrolled bouncing in the back. Initially started at +8 and -4 and kept clicking down to -20. Set it to -25 to roll to the track.
I should say that is a track setting, and I didn't read completely that you are were looking for street.

Try +0 on top, and -25 on the bottom adjuster then make small changes to both until its where you like it for street.
 

Grant 302

OPM Spent: $665,833
Moderator
Messages
7,322
Reaction score
2,086
Location
In the OC
Re: Help me understand my new coilover adjustments (JRi - CorteX)

twistedneck said:
That looks exactly like my setup. when i get home i'll take a look at number of clicks. thanks!!

Ok I got home and took a look. I have that exact same shock spring combo and adjuster. It has a total of 72 clicks. Its 22 clicks away from the full + (I assume that's 14 clicks more rebound high speed rebound damping than middle?)..
Until Filip or CorteX responds, I would aSSume that it's 60 clicks and the extra 12 are 'over-run' that (I think) do nothing like mine are past -25. And that would make your 'mid-point' -30. The reference point is from full stiff. In JRi speak, you'd just call the as-shipped baseline -22. I'd start there, if you haven't already started your testing...unless somebody with experience says otherwise.


ilesjohn said:
I should say that is a track setting, and I didn't read completely that you are were looking for street.

Try +0 on top, and -25 on the bottom adjuster then make small changes to both until its where you like it for street.
Gotcha! 8) I left the HS rebound in place at +8 in the back, because I was looking just to transport to the track and make as few changes as possible and doing only the low speed clicks is easy. That was the right call since I barely made my first session. I will take your advice on starting at +0 when I start adjusting for street use. Thanks!
 

2013dibgt

TMO Advanced
Messages
119
Reaction score
5
Location
PA
Re: Help me understand my new DA coilover adjustments (JRi - CorteX)

Welp..looks like I'm now in the same shoes as others on this one. Just finalized the install of my JRi DA struts today and now I'm at a point of wanting to make a few adjustments before I take the pig on its maiden voyage.

Man... I gotta say I am not a fan of the adjustment knobs on these things. The top knob is better due to having "clicks" but I still don't like the fact that their is no Stop point at full stiff (ie.. Cranked all the way towards the sky). I damn near lost the little ball bearings that control the clicks but luckily saw them starting to poke out of the shaft before I went too far.

The Compression (bottom) knob is about as useless as tits on a Bull! When I turn mine it rotates the whole assembly (ie..Top and bottom knobs) at the same time with a level of resistance to the turns that I'm not feeling very warm and fuzzy about. Seems shady to me.

Am I missing something here? As a comparison, my rear Penske DA's which also use "Sweeps" for compression are silly easy and there is no question what your adjustments are doing.

Looks like I'm going to have to call JRi and have them decrypt what's going on since RTFM only applies to those who actually got a manual to begin with. :mad: :eek: :p
 

Grant 302

OPM Spent: $665,833
Moderator
Messages
7,322
Reaction score
2,086
Location
In the OC
Re: Help me understand my new DA coilover adjustments (JRi - CorteX)

You might not like this suggestion: Buy the JRi pin adjusting tool. I only got it after losing one of my allen wrenches when it sprung out of the adjuster. :mad:

Movement of the Low Speed (clicker) is normal with the High Speed Rebound adjuster.

Count your clicks, write them down and know when you are testing for the last one. Haven't had an issue myself.
 

TMO Supporting Vendors

Top