Cortex JRi Dampers - Dyno Plots?

[El Jefe]

For those of you who bought the Cortex JRi dampers, did you receive dyno plots with your purchase? If so, would you mind posting the plots?

 

[neema]

FWIW I didn't receive any dyno plots with my purchase

 

[VoodooBoss]

No plots here either. I know a guy on Team Shelby that just purchased the SA JRi's and had them tested. I'll post the results when I have them.

 

[DGRacing]

Hmmmm. I wonder why Filip didn't give any. They have to be valved for a specific spring rate. Did they at least do that? Once they get pressurized and valved for your spring rates they have to dyno them to ensure all the adjustments are working properly and within spec.

 

[VoodooBoss]

Is this really that big of a deal? I hadn't even thought of this until I saw this thread. The JRi's are made to CorteX specs. Having met and talked to both and seeing numerous Mustangs on track with this setup I trust what both JRi and CorteX are doing. The dampers aren't valved for a specific spring rate they're valved for a range of spring rates and you use the adjusters to fine tune. I have 450 lb front and 250 lb rear springs.

 

[Grant 302]

Hmmmm. I wonder why Filip didn't give any. They have to be valved for a specific spring rate. Did they at least do that? Once they get pressurized and valved for your spring rates they have to dyno them to ensure all the adjustments are working properly and within spec.

I didn't wonder at all. But I might be making the wrong assumptions about their possible reasons.

I did talk to Filip quite a bit about the damping characteristics and particularly about the nature of the HSR adjustment. So I got what *I* needed to get my head around making adjustments. A dyno chart *may* have gotten me what I needed...but with so many combinations of settings, I don't know how that would have been practical for helping me make adjustments. I did assume that they are tested, but would only expect them to be run at say their baseline, as-shipped settings. I don't know how useful that would be.

If anybody in this thread has any questions about the damping properties, I suggest you contact Filip directly. He answered every question of mine without hesitation.

That said, I've been meaning to start a thread about customer opinions of the JRi units. Frankly, I've been simply amazed by the change in grip, and I'm surprised I haven't heard anyone else say the same.

 

[JScheier]

The dampers aren't valved for a specific spring rate they're valved for a range of spring rates and you use the adjusters to fine tune. I have 450 lb front and 250 lb rear springs.

^This. Unless you are purchasing dampers with true, custom valving, you are getting dampers that meet or come exceedingly close to a 'spec' for a 'range' of spring rates. This is common, as most resellers do not have the shock dyno, fixtures and software to accurately dyno shocks. Not to mention that if the right rear shock has slightly better / worse response at a setting than the left rear shock, it opens up a whole new level of issues in customer service.

FWIW, I get mine dynoed before & after a rebuild just to see what's going on. This helps me better determine future rebuild / service intervals (other than, "Oh $hit... fluid is leaking out of it).

 

[DGRacing]

^This. Unless you are purchasing dampers with true, custom valving, you are getting dampers that meet or come exceedingly close to a 'spec' for a 'range' of spring rates. This is common, as most resellers do not have the shock dyno, fixtures and software to accurately dyno shocks. Not to mention that if the right rear shock has slightly better / worse response at a setting than the left rear shock, it opens up a whole new level of issues in customer service.

FWIW, I get mine dynoed before & after a rebuild just to see what's going on. This helps me better determine future rebuild / service intervals (other than, "Oh $hit... fluid is leaking out of it).

My ASTs were valved specifically to my springs from the manufacturer, but I got mine fully built. I wasn't aware if these JRi's were being 'built' or not. Of course they _will_ work within a range. It's not like the damper is going to malfunction but there is a sweet spot in the dyno curve and the gas pressure has to be suitable to the spring rates YMMV. For off the shelf kits I'm sure that range is very wide.

 

[DGRacing]

I didn't wonder at all. But I might be making the wrong assumptions about their possible reasons.

I did talk to Filip quite a bit about the damping characteristics and particularly about the nature of the HSR adjustment. So I got what *I* needed to get my head around making adjustments. A dyno chart *may* have gotten me what I needed...but with so many combinations of settings, I don't know how that would have been practical for helping me make adjustments. I did assume that they are tested, but would only expect them to be run at say their baseline, as-shipped settings. I don't know how useful that would be.

If anybody in this thread has any questions about the damping properties, I suggest you contact Filip directly. He answered every question of mine without hesitation.

That said, I've been meaning to start a thread about customer opinions of the JRi units. Frankly, I've been simply amazed by the change in grip, and I'm surprised I haven't heard anyone else say the same.

I don't think the shock dyno chart is useful really, just more of a record of the very expensive parts characteristics. It's nice to have in the cars documentation is all.

 

[El Jefe]

Is this really that big of a deal? I hadn't even thought of this until I saw this thread.

Yes and no. This wasn't an attack on Cortex. I bought my JRis from MM and did't receive dyno plots either. I'm more trying to figure out if the dampers are built with a dyno at JRi or just assembled. For $1K a corner, yes, I assumed they would be checked on a shock dyno. It also would help me learn how much they wear down over time. While a before and after plot is great when you get them rebuilt, it doesn't show you a comparison from new.

Having said that, I still think they are amazing dampers and don't have any regrets with my purchase. If I was to do it again, I would have shipped them off to get tested before I installed everything.

 

[Grant 302]

Yes and no. This wasn't an attack on Cortex. I bought my JRis from MM and did't receive dyno plots either. I'm more trying to figure out if the dampers are built with a dyno at JRi or just assembled. For $1K a corner, yes, I assumed they would be checked on a shock dyno. It also would help me learn how much they wear down over time. While a before and after plot is great when you get them rebuilt, it doesn't show you a comparison from new.

Having said that, I still think they are amazing dampers and don't have any regrets with my purchase. If I was to do it again, I would have shipped them off to get tested before I installed everything.

I understand why you're asking now, but you're barking up the wrong tree. The only data/plots that would help you are ones from the MM units. I suspect even the plots from Rick's SA units would be different from my DA units...even if we could figure out what settings were 'equivalent' for testing purposes. The MM DA units are *very* different from the CorteX DA units. The MM DA adjusters are for compression and rebound while the CorteX DA adjusters are for low speed compression/rebound and high speed rebound only. So the CorteX dyno plots would be totally useless for comparing to yours new or worn.

Hope that helps!