Review: JRZ RS-ONE for E92 M3

[Expert@ApexWheels]

PRODUCT REVIEW: JRZ RS ONE FOR THE BMW E92 M3

We know it's tough to find well-written suspension reviews from people who know what they're talking about, let alone one that is chassis specific. "Good ride quality" and "good handling" means something different to everyone. One customer from our recent group buy provided us with a very nicely detailed and specific review of his RS-ONE setup and we wanted to put it out there as a testament to why we stand behind it. Below are his words:

"My name is Ken Yip (@kppy86) and I picked up my JRZ RS One suspension kit for my E92 M3 track car through a group buy hosted by APEX on GangUp.com.








For ~20 track days with my car, I kept running the stock EDC suspension. I thought it was pretty good – it is. However, I started really pushing the car and started to find myself riding on the bump stops all the time. While on track, this meant the car was extremely twitchy – use the whole track on corner exit would mean the rear end would snap out on me very quickly and the car took quite some time to get settled between turns. I finally decided to join the group buy when I got feedback from coaches that I either need to adapt to the soft stock suspension or upgrade.








It is a night-and-day difference between my stock suspension and the JRZ system. Where apex and corner exit curbing would upset my stock suspension, the JRZ RS One shocks simply soak it all up, letting me focus on driving. At Laguna Seca, I’m still working my way to figuring out the increased capabilities. It’s already become very evident that I can be more aggressive in turns 2, 3, 4, 6, 9, and 10 now.









On my past E46 M3, I had the popular Koni Yellow + springs setup. I hated it, as it ruined the car and driving over any bumps felt like I was going to tear my car’s frame. On my E92 M3 with JRZ RS One, the quality of a true high-end shock is clear. I have stiffer springs and components than my E46 M3, but with the shocks set between 1-3 clicks for street, it is noticeably stiffer than the Koni setup, but I don’t fear the car falling apart.



This is where the quality shines – it’s not just a full-stiff setup that can keep the car on track. It can soak up bumps both on and off-track to maximize grip while giving the confidence of fast response. Some people think you need a back-breaking ultra stiff feel to go fast, I disagree. It feels cool once in a while, but if often means you’re losing contact patch with the ground.



I’ve attended 2 SpeedSF HPDEs so far with the new JRZ suspension. Street mile wise, it’s mostly been driving to/from tracks and maintenance as I don’t daily drive this car. My guess is ~600 street miles since the install in early December.





Thunderhill East bypass on 12/15/2018 was a very wet day. Couldn’t set a proper lap time with traffic and the rain, so my best was 2:07.38 with a virtual best of 2:01.63. (HLT).






Laguna Seca on 12/30/2018 was my first real chance to test it out. Ran a 1:42.48, ~2.5 seconds faster than my prior PB. Had Joe, one of the coaches drive my car for a few laps and he set a 1.41.32, giving me good feedback on the setup and indicated that 1:40 or below is possible with more adaptation to the car (using Waylens 10 Hz GPS).


Making adjustments to the rear dampers.

EC-7 Track Wheel Setup
Front & Rear: 18x10" ET25 with 275/35-18 Nitto NT-01 tires

SM-10 Street Wheel Setup

Front: 18×9.5” ET22 with 265/35/18 Michelin PSS
Rear:18×10.5” ET22 with 285/35-18 Michelin PSS


Other Modifications

• JRZ RS One Suspension
• Hyperco 550/800 Springs w/ Front Helper Springs
• Ground Control Rear Weight Jacks & Race Camber Plates (-3.5 F)
• Rotora 6p/380mm & 4p/355mm BBK with PMU 999 Pads
• Dinan Front Sway Bar
• Dinan Front Control Arm Monoballs
• BMW M Performance Exhaust v2 (passes sound check!)
• CSF Oil Cooler, Radiator and Power Steering Coolers
• Slon Workshop Baffled DCT Oil Pan
• ESS ECU Tune
• BMW GTS/Euro DCT Tune
• Vibra-Technics Fast Road Engine Mounts

[bajaracer]

Thank you for posting this as I was already starting to get my spring rates figured out to place my order via the group buy.

[donut_boi]

Thank you for sharing your experience!

If I may ask, I kind of see an extension for the rear adjusters protruding from the panel cover, which one did you go with?

Thanks!

[derbo]

kpewpew wrote the review.

[kyippee]

Hey guys! The JRZ suspension is the real deal.

To answer quickly, donut_boi - the rear adjuster extensions came with the kit, not sure what options there are out there. You may want to check in with APEX to confirm you'll get it.

I went to Thunderhill East this past Sunday to get some proper laps in. Great event put on by Aston Martin Owners' Club with only 40 cars, 2 run groups, alternating 30 minute sessions all day.

Had my sister and friends ride along with me. Did a lot of curb hopping and my friends confirmed - it is an amazing setup that let me go wild over curbing without getting upset. I ran 13 out of 24 clicks, and I think I can still go stiffer. My friend who has a TCK 2-way coilover kit on his 135 is converted too.. I think. His TCK kit doesn't even fit properly - he had to cut into his shock towers to be able to adjust. What a joke, huh?

Additionally, Performance Technic does effectively 100% of the work on my car and they have been great supporters for a weekend warrior like myself. I can't recommend them enough. I know we are lucky to have several amazing shops in the SF Bay Area, and I continue to drive 40 miles through the crappy I-880 traffic because they are knowledgeable professionals who put up with my crap. Up next on the car are seats, proper corner balancing, raising the front height a bit, re-aligning, deleting front lip & sideskirt extensions, and just maintenance.

I still need to gradually work up my confidence in the car's expanded capabilities. Especially turn 8- I can definitely brake less and shave some time off there. Cresting and landing at high speed over the bypass is scary, and I felt more confidence with the new setup. Transitions from turns 3 through 6 are also greatly improved. The car settled and changed direction quicker. Turn 10? What a dream. I can run over the apex curbing and not upset the car at all. I scared a miata, poor guy flew to the left at corner exit because I was just hauling through the corner. I also went jumping over the turn 15 inside curbing during my cyclone PB lap. What a blast! I was able to keep the throttle down.

Could have ran a 2:00.xx bypass but I didn't want to apex into a car pitting at turn 14. Videos embedded and some select photos attached. The DB11 AMR was losing his shit when I was going for a pass.

Cyclone config:
New PB 2:05.58
Virtual best 2:04.24

Bypass config:
New PB 2:02.74 lap starts at 2:34 PM (see top left corner for time)
Virtual best 2:00.44

[PerformanceTechnic]

Awesome write up! Love the photos too...

[kyippee]

Update: Had a great day at Sonoma Raceway with HOD, running in Group D on Sunday. Beat my past PB by ~6 seconds, running a 1:51.xx.

The JRZ Suspension customized by APEX to fit my needs continues to amaze me.

And turned pretty consistent 1:53s the session before

[Montaver]

Great write up, thanks for posting. How do you find them on the street?

[kyippee]

Originally Posted by Montaver

Great write up, thanks for posting. How do you find them on the street?

Very surprisingly comfortable. On street, I set all the dampers to 1 click out of 24. Feels a bit floaty over higher speed highway bumps, but I'm not hearing any rubbing. Feels like stock ZCP suspension on normal or sport setting.

[derbo]

Originally Posted by kpewpew

Very surprisingly comfortable. On street, I set all the dampers to 1 click out of 24. Feels a bit floaty over higher speed highway bumps, but I'm not hearing any rubbing. Feels like stock ZCP suspension on normal or sport setting.

I would imagine dialing a few more clicks will benefit highway bumps so it isn't as floaty. We can get to highway speeds very quickly!

[kyippee]

Originally Posted by derbo

I would imagine dialing a few more clicks will benefit highway bumps so it isn't as floaty. We can get to highway speeds very quickly!

Downside is that it's far too stiff for the broken city streets on the way home. Not worth the trade off for me. Any stiffer and I feel like I'm bending wheels in downtown SF.

This is street driving anyways, not track. I accidentally left the suspension on full soft at Sonoma first session and the car was looser but still hung with a Dodge Viper. I think it's good enough for highway cruising

[derbo]

Originally Posted by kpewpew

Downside is that it's far too stiff for the broken city streets on the way home. Not worth the trade off for me. Any stiffer and I feel like I'm bending wheels in downtown SF.

This is street driving anyways, not track. I accidentally left the suspension on full soft at Sonoma first session and the car was looser but still hung with a Dodge Viper. I think it's good enough for highway cruising

Even like 1-2clicks up?

[kyippee]

Update.. 2:00.065 at Thunderhill East bypass. Car is great. Ran on 15 clicks all around. Good enough to get 3rd place in SpeedSF S3 class

Video of that lap:

Another session, qualifying where I chased an M2 comp:

[kyippee]

Soo.. now the car has GTS front and rear aero. I did indeed need to run more clicks on street. With full soft, highway undulations and crests resulted in the front lip scraping.

With 5 clicks, the recommended street level, it seems to be gone now! Still pretty comfortable.

[e90///M3]

What's the recommended mileage for rebuild for these kits?

[hungryhippo]

Impressive times for your mods

[kyippee]

Originally Posted by e90///M3

What's the recommended mileage for rebuild for these kits?

I don't know.. Expert@ApexRaceParts any guidance?

[aus]

So bummed the group buy didn't get enough people to go through at the max discount for these.
The early units had issues, but the newer units seem solid and get great reviews.
.

[kyippee]

I continue to be impressed with the JRZ suspension, even though it is "just" the entry level kit. I have more to improve as a driver, but I did well enough recently at Laguna Seca with Speed SF's TT challenge. Scored 1st in my class (S3).

Next up is May 25th at Sonoma Raceway. I feel pretty good having done a 1:51 my last visit, and want to drop the time down a little while getting more seat time there.

Blog post with recap: https://www.speedsf.com/blog/2019/4/...ay-laguna-seca

[SYT_Shadow]

Originally Posted by Expert@ApexRaceParts

On my past E46 M3, I had the popular Koni Yellow + springs setup. I hated it, as it ruined the car and driving over any bumps felt like I was going to tear my car’s frame.

I have the same feedback about koni yellows on my E46 back in the day, absolute fucking SHIT

Yet people continue to tell me it's a great option.


I removed them from the car and threw them away instead of selling them, I wanted to spare other humans from dealing with that shit