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CorteX JRi Double Adjustable Front & Rear Damper Adjustment Settings


Because racecar.
Arizona, USA
JJ is one of the founders of JRi and now runs Ultimate Performance. I talked with him on the phone a couple months back and he has a wealth of knowledge of his own product, as well as damper design in general from his days at JRi and also prior work at Penske Racing Shocks.

Compliance is key with bumpy surfaces, especially for every day driving.

That SUCKS about your dampers, though! :( I would be furious.
3. JRi rear shocks are leaking. Working w JJ Furillo who is a JRi shock expert from North Carolina. He will rebuild them pretty cheap and put better internals in to prevent future leaks.
[email protected].......
I had my JRi SA setup rebuilt about a year ago because I noticed the rears were obviously leaking..and I live in Japan so shipping was HEFTY. After 1 year they're leaking again.... getting pretty annoyed with this.


TMO Race
Dearborn, MI
Well I guess that's the story all over the world....... Thats quite a drop in spring rate!!! I was thinking of going from 600/350 to 500/300..... But 150 in the rear??? Must be quite the shock!!
On the smooth roads the car is not in the same control as it was before and at the track the high speed stuff aint nearly as planted i bottomed out the rear shocks hard on a high speed rut section at the bottom of a hill. i actually heard a smack of metal! but i've since moved up to 425 front, with the factory GT front sway bar and kept the 150 rear, and use the super thin 18mm rear sway bar.

Oh in case you guys are wondering i sent the shocks back to JRi for full repairs. it wasn't bad.. the leak was cause by a scratched shock rod ($320) and one of the adjuster setups was so trashed it couldn't be salvaged $30 i think? i opted for the new Schrader valve Nitrogen fills on the bottom instead of the Presta - i never use that part of the shocks but hell why not (upgrade of $170 for the pair). Also got brand new adjuster knobs and a new poker tool for the high speed rebound. with shipping and everything it was $930. Worth every cent. Thanks for the great Service Marty Flannery at JRi.

The car drives now like it NEVER drove before so smooth no clunks finally (i stopped using a wrench to tighten the top nut, i used an impact this time and it was so damn easy! no more holding the shaft with cloth covering the jaws). its actually handling now like i always wanted it to. oh and here is an example of stellar service and why i worship Cortex stuff.. Filip answered my emails within 1hr on a Monday night and then again at midnight when i sent him a Tuesday late night note! Hand drawn diagrams and everything. I highly recommend you buy as much Cortex stuff as possible. Hope your setups are grippy! Jeff Check.


TMO Race
Dearborn, MI
Thanks for the update Jeff. Glad it worked out and that it wasn’t an unreasonable cost to fix clowny mistakes from the other guy.

But I’m not surprised that you have issues bottoming out with 150 lb./in. springs.
Grant.. i thinknthe rear frequency is a tiny bit slow now formthe faster 425 fromts so im going to install a 175 rear today. i belive something is coming lose in the rear shocks / mounts so i need to inspect it anyway. will report back on it. fyi w that huge jounce bymper on the resr shock i dont think it can bottom out so it must have been a lose or worn fastener. stay tunrd

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