JRZ RS1 from Bimmerworld

[VictorH]

The great thing about the forum is the ability to exchange information and help with decisions on aftermarket parts or accessories. I have been riding on a stock E90 EDC suspension for the past 3 years and while the suspension is a pretty good dual purpose suspension, i.e. street and track it’s a bit soft for the track. I’ve put several thousand track miles on this suspension and it’s held up well with no sense of wear or loss of performance. So, starting approximately one year ago the search was on for an upgraded suspension system. The goals of the system for me were to preserve street manners with a reasonably compliant set up as well as adjustability. I didn’t want to go with a race-type set up due to cost and complexity and I wanted something a bit higher performance than Koni or Bilstein.

The other item for me was to be careful about not getting a set up that is too stiff. My last dual-purpose street and track car was brilliant on the track, but it was so stiff on the street that I hated it, and most of my driving was on the street, didn’t want to repeat that mistake again. I’ve done the same thing with camshafts. Install a long duration, high overlap cam and on the track it’s so fun and tractable at high rpm but then on the street you say to yourself, “why did I ever choose this cam?”

So over time I narrowed the choices down and was thinking about a Moton set-up, AST or JRZ. After talking to a few people including James Clay at Bimmerworld as well as Brian at JRZ I decided on the RS1 system. It was designed to be a truly dual purpose street and track shock with an emphasis on good street-ability and the ability to convert it to a reasonable track set up in less than 2 minutes. I had several conversations with James at Bimmerworld and decided to go with the JRZ RS1 as well as Hyperco springs which evidently come in matched pairs by poundage.

My goal for the new set up was to be 20-30% better on the track with minimal loss of daily driving street comfort/quality. James recommended 425 lb front springs with 700 lb rears. I drove up on Wednesday morning to Bimmerworld in Dubin, VA (very pretty little town with lots of trees now changing color) and by 4:30PM that same day I was on the road on the way home.

Impressions so far, which does not include any real cornering or handling impressions as the drive was all freeway and moderate traffic. Firstly, road feel through the steering wheel and your seat is improved. This is only a consequence of stiffer springs and more vibration and road noise transmission through the chassis. I like it, though, as the steering feel in the M3 is pretty good, it’s not as good as my gold standard which is an early 1970s 911 T, E or S. Those cars you can drive blindfolded and be able to tell the passenger what type of pavement, asphalt or concrete, grate or manhole cover and just about any other surface irregularity. Road feel is better, i.e. more feedback to the driver which I like. Nothing is free so the downside is that there is a bit more noise in the cabin especially over rough surfaces, but it still doesn’t stop you from enjoying the radio or talking with your passenger.

The overall ride quality is really just about the same as stock. The change is so small as to be almost trivial. Little bumps are just like stock and for larger bumps I think the compliance of the RS1 is better than stock. I have the shocks set at 4 clicks from full soft which is great for the street. The only thing perhaps and I just noticed this once is that over a series of bumps there might be a bit more “bounce” in the front end that is not present in the stock system. I’m sure this could be fixed with one or two more clicks of firmness to the shock.

I’ve included a couple of pictures of car and shocks below. The overall ride height of the car is approximately ½” lower than stock. I actually thought that the car was at stock height when I picked it up, but when I put the car up on my hoist it was evident the clearance between the jack pad and the jack point was about a half inch less. I’m looking forward to testing this out at the track but don’t have anything scheduled as of now. Only other point is to say how good the customer service is at Bimmerworld with knowledgeable people, they kept me up-to-date as to progress on the car and James was great at explaining how to set up the car for the track, what to expect and how to adjust for different handling characteristics that are amenable to shock valving adjustment.

[flipm3]

Great to see more people picking up the JRZs!

This is at the top of my list currently for my E46 M3. Hopefully I can make a decision by the end of the winter!

Keep us posted as you put more miles on the car!

[M3SQRD]

Victor, congrats on the new RS1 setup Definitely give us an update once you've had a chance to spend more time with the setup on the street and track.

[STALKER]

Congrats. I'm sure you are going to love them.

Could you post your ride heights at each corner whenever you have time, I need to reset my ride heights. Thanks!!!!

[CBS]

OP Congrats and thanks for the review. I'm hearing good things about JRZ.

I'd be curious to hear your thoughts after more street and track time.

I would agree, the Folks at Bimmerworld are really helpful. Sounds like you received similar suspension setup instructions as I did for both street and track. That helps take the guesswork out.

Enjoy!

Chris

[akh23456]

great review sir, i plan on getting Jr-z hopefully soon.

[klammer]

Originally Posted by M3SQRD

Victor, congrats on the new RS1 setup Definitely give us an update once you've had a chance to spend more time with the setup on the street and track.

Agreed. Keep us posted. Stance looks perfect.

[STALKER]

Victor, I run mine at 5 clicks from full soft in the front and 4 out back for street use. I have noticed the slight "bounce" you are referring too as well. But I had the same thing with my Dinan set up over really small harsh bumps that are back to back.

The RS1s def absorb the big harsh stuff amazing.

Did you go with GC plates? Looks like you did.

Bimmerworld is great to deal with, I have nothing but good things to say about them.

[JamesClay]

Thanks for the positive feedback! I did a lot of road testing last week - not driving, but actual testing with a designated route that has specific surface characteristics and issues along the way, including cracks from freezing, transition seams, larger bridge seams, rough concrete, chunked-out asphalt, and a very smoothly bumpy strip in front of a stoplight where trucks stop and have rutted up the surface. The JRZ really is very pleasant on the wide variety of surfaces. There is a bit of damping range to use, and all of it is truly usable. At these streetable spring rate ranges, even with the damper dialed all the way up there is still not brutal. They did a good job hitting the mark with valving for the intended use of the shock.

One unexpected point is that half of this is on my way home from work, so my pure stock F30 ran a section unplanned. I can confirm, and was surprised, that the initial hit of some of the sharper bumps is actually harder in this stock BMW suspension than it was on my E46 with JRZ and 600/700 springs.

[kchu221]

nice! i love my JRZ's...

[flipm3]

Originally Posted by JamesClay

Thanks for the positive feedback! I did a lot of road testing last week - not driving, but actual testing with a designated route that has specific surface characteristics and issues along the way, including cracks from freezing, transition seams, larger bridge seams, rough concrete, chunked-out asphalt, and a very smoothly bumpy strip in front of a stoplight where trucks stop and have rutted up the surface. The JRZ really is very pleasant on the wide variety of surfaces. There is a bit of damping range to use, and all of it is truly usable. At these streetable spring rate ranges, even with the damper dialed all the way up there is still not brutal. They did a good job hitting the mark with valving for the intended use of the shock.

One unexpected point is that half of this is on my way home from work, so my pure stock F30 ran a section unplanned. I can confirm, and was surprised, that the initial hit of some of the sharper bumps is actually harder in this stock BMW suspension than it was on my E46 with JRZ and 600/700 springs.

I need some JRZ or MCS on my E46 M3....ASAP....

[CBS]

^ flipm3 Sounds like you may be next!

[flipm3]

Originally Posted by CBS

^ flipm3 Sounds like you may be next!

Haha...I'm working on it.

Talking to M3SQRD and exchanging emails literally on nearly a daily basis. Then buying his former KWs from his previous E46. Well to say the least, he has got me lusting over high end dampers like crazy!

I am just waiting it out until next year to make my final decision.

[VictorH]

Originally Posted by STALKER

Congrats. I'm sure you are going to love them.

Could you post your ride heights at each corner whenever you have time, I need to reset my ride heights. Thanks!!!!

Corner heights are as follows:
Driver's Front 26 1/8"
Passenger Front 26 1/8"
Driver's Rear 25 5/8"
Passenger Rear 25 3/4"

Yes, those are ground control adjustable camber plates.

[CBS]

^ if you're talking to M3SQRD then you're in trouble! He'll have you convinced in no time!

[M3SQRD]

Originally Posted by flipm3

Haha...I'm working on it.

Talking to M3SQRD and exchanging emails literally on nearly a daily basis. Then buying his former KWs from his previous E46. Well to say the least, he has got me lusting over high end dampers like crazy!

I am just waiting it out until next year to make my final decision.

Originally Posted by CBS

^ if you're talking to M3SQRD then you're in trouble! He'll have you convinced in no time!

Hey, I thought I heard a ringing in my ears

I see what's happening here, you're telling the "boss" it's all my fault you had to spend $$$ on your new suspension

[1MOREMOD]

your fender liners look super clean. mine look like ive been off roading.

[STALKER]

Originally Posted by VictorH

Corner heights are as follows:
Driver's Front 26 1/8"
Passenger Front 26 1/8"
Driver's Rear 25 5/8"
Passenger Rear 25 3/4"

Yes, those are ground control adjustable camber plates.

Much appreciated!!!!
These are from the ground to the lip of the fender? Im going to get my heights adjusted next week. Im dropped about 1.5" all around right now I think.

[STALKER]

Originally Posted by M3SQRD

Hey, I thought I heard a ringing in my ears

I see what's happening here, you're telling the "boss" it's all my fault you had to spend $$$ on your new suspension

Isn't that how we all get away with it??

[M3SQRD]

Originally Posted by STALKER

Isn't that how we all get away with it??

So true - always better to ask for forgiveness

[VictorH]

Originally Posted by STALKER

Much appreciated!!!!
These are from the ground to the lip of the fender? Im going to get my heights adjusted next week. Im dropped about 1.5" all around right now I think.

Yes, those are from the ground to the lowest edge at the highest point on the arc of the fender.

[M3SQRD]

Originally Posted by VictorH

Yes, those are from the ground to the lowest edge at the highest point on the arc of the fender.

What diameter wheel and tire sizes are you using? You need to account for the diameter of the wheels-tires when measuring ride heights from the ground.