[TSM330i]

Great info Charles.

You're right, it's a very difficult thing to explain to someone when you get good coil-overs on a car.
My summation of the difference is that it takes our cars (BMW 3-series) and goes from a sport sedan/coupe to a sports car.
The utter control over body motion, suspension reaction time and how quickly the car settles over any kind of road imperfection is mind blowing.
You know from yourself the first time you drove my car. It's just so flat and hooks so hard and doesn't let go.

BTW: You're going to LOVE the PSS!

[swifty]

Originally Posted by CJ421

You can get the RS1s with adjustable collars as Harold noted. That would give you adjustable height independent of the spring. My setup by comparison is dependent on the springs for ride height. As far as spring recommendations ... the ACS ones are the only ones I've heard of being recommended with this damper. Though I don't see why you could not use a standard spec 335 or M3 spring. I forget the exact reasoning why I don't have 335 springs in the front, just that they did not work. The rear is M3 because it's an M3 style shock and I have the M3 lower rear camber links.

These JRZ dampers are quite different because the they are designed to compensate for the spring and act in ways you would not expect of a damper. It's still important to choose the right spring (the key number is the spring rate you want); just realize a JRZ damper is far more effective than a 'normal' damper. I am still wrapping my head around the behavior of these dampers; since getting them installed I now understand things I could not have understood reading a book (which is what I've been doing for months). I'm usually not fascinated by things but am overwhelmed by the capabilities and sheer power of these dampers (and how utterly controlled it is). I wish I could explain better but I think it must be felt. I'm calling it magic for now.

Now I'm not going to stare at your tires at every meet.

Regarding ride height - my car has settled a tiny bit. Can't tell in a picture but it's lower. Going out of my driveway I slightly scrape the air deflector things under the front bumper. That did not happen initially. Here is what the car looks like, almost like factory with a slight rake towards the front. The stance is visibly different in person.

Can you provide the spring rates you have for the front & the back? Thanks for all the info you have posted.

[CJ421]

Originally Posted by TSM330i

Great info Charles.

You're right, it's a very difficult thing to explain to someone when you get good coil-overs on a car.
My summation of the difference is that it takes our cars (BMW 3-series) and goes from a sport sedan/coupe to a sports car.

Thanks Rob. I'd equate going to a good set of c/os (or magical ones, in my case) even greater than going to an LSD from the open diff.

Originally Posted by swifty

Can you provide the spring rates you have for the front & the back? Thanks for all the info you have posted.

AC Schnitzer doesn't disclose the spring rates despite my (and VAC's) prodding.
Only reason I went with them was because JRZ and VAC recommended them. I haven't regretted the choice.

[E90335iflyer]

Very detailed review OP!

This looks like a great kit. My e90 is my DD, but the stock suspension is horrible so replacement must happen soon. I am done with twin tube stuff(my personal choice) so this Monotube has my interest. Super expensive external canister suspension can go on my other two toys.

What does something like this set me back? Any forum sponsors sell these? I would rather give my business to forum sponsors who give contribution.

[CJ421]

Thanks!

Call VAC for a quote but here's the link to the RS1s on their site:
http://store.vacmotorsports.com/jrz-...e87-p2732.aspx

VAC is a forum sponsor. Mike@VAC is their rep here.

[E90335iflyer]

Originally Posted by CJ421

Thanks!

Call VAC for a quote but here's the link to the RS1s on their site:
http://store.vacmotorsports.com/jrz-...e87-p2732.aspx

VAC is a forum sponsor. Mike@VAC is their rep here.

Thank you.

Anyone else? I usually like to see quotes from at least 3 vendors and speak to each before placing my order. Price is not the biggest factor, but customer service is. Had too many experience before going with the best quote but also getting the worst customer service after the purchase!

[badblk335i]

Beautiful review as always Charles. Your car has a killer stance and I am looking forward to going for a ride real soon!

[Mike@VAC]

Originally Posted by E90335iflyer

Thank you.

Anyone else? I usually like to see quotes from at least 3 vendors and speak to each before placing my order. Price is not the biggest factor, but customer service is. Had too many experience before going with the best quote but also getting the worst customer service after the purchase!

We have 6 full time folks who handle sales. I am also available pretty much 24-7 via PM, email, text etc.

We obviously sold a kit to Charles and his feedback is here. We have hands on experience installing dozens of JRZ suspension solutions.

fun facts:
-our main tech ran JRZ exclusively on his Grand Am race cars.
-We run JRZ on our E36 race car which is quite a good performer given it's heft. (esp when driven by Aaron Povoledo)
-While in Germany for the PMW Show (where we exhibit) last year, we stopped by JRZ to meet with the brass. Pics here: http://www.e90post.com/forums/showpo...59&postcount=2
-Our track day partner, pro driver Aaron Povoledo can be seen in the awesome JRZ video here. https://www.opentrackdayevents.com



Please LMK if you have any questions, I can def help

[Mike@VAC]

Pic of the fixed height kit.

[CJ421]

Thanks Mike for the input and that is a fantastic picture!

Originally Posted by Mike@VAC

We obviously sold a kit to Charles and his feedback is here. We have hands on experience installing dozens of JRZ suspension solutions.

fun facts:
-our main tech ran JRZ exclusively on his Grand Am race cars.

He is an AWESOME person and a good percentage of the reason I go to VAC. He personally sets up my car and to say he knows his stuff is an understatement.

[cvc 22349a]

What does JRZ do for bumpstops? Do the struts have internal bumpstops like Bilstein?

Charles: Any idea how much of a drop you got up front from using camber plates v. the oe strut mounts?

[CJ421]

Originally Posted by cvc 22349a

What does JRZ do for bumpstops? Do the struts have internal bumpstops like Bilstein?

Charles: Any idea how much of a drop you got up front from using camber plates v. the oe strut mounts?

Interesting question about the bumpstops, I'm going to have to ask VAC about that one ...

Regarding ride height - not sure what the camber plates do for that either. Regarding an earlier question you asked about the ride height ...

Originally Posted by cvc 22394a

Also, why did you go with M3 springs instead of 335i? That's why your ride height is what it is.

It's actually not because I am using M3 springs; VAC tried 335 springs and it was the same height. The M3 spring isn't any taller, just a tad wider. Apparently the ride height behavior is just how this damper is.

I imagine most people will buy the RS1 adjustable ride height version.

[cvc 22349a]

[quote=CJ421;12337904]Interesting question about the bumpstops, I'm going to have to ask VAC about that one ...

Regarding ride height - not sure what the camber plates do for that either. Regarding an earlier question you asked about the ride height ...

It's actually not because I am using M3 springs; VAC tried 335 springs and it was the same height. The M3 spring isn't any taller, just a tad wider. Apparently the ride height behavior is just how this damper is.

I imagine most people will buy the RS1 adjustable ride height version.[/QUOTE]

I wouldn't. I think you made the right choice going with a wider diameter spring v. a c/o spring.

[CJ421]

Originally Posted by cvc 22349a

I wouldn't. I think you made the right choice going with a wider diameter spring v. a c/o spring.

Good to hear coming from you. I have no regrets about keeping the ride height. There is precious little room to lower these cars and maintain the standard geometry.

FYI car is at VAC now for some upgrades - Michelin PSS (235/265), the ETS 5" intercooler, a brake fluid flush, and VAC's beautiful stud kit!

[turugara]

Originally Posted by CJ421

FYI car is at VAC now for some upgrades - Michelin PSS (235/265), the ETS 5" intercooler, a brake fluid flush, and VAC's beautiful stud kit!

Catching up!

Only seats and BBK left afterwards

[CJ421]

Originally Posted by turugara

Catching up!

Only seats and BBK left afterwards

*hands over ears* blah blah blah can't hear you!

Man I just can't catch a break ... brake ... I need brakes ... because racecar ...

My mind is just about to go completely.

[turugara]

Originally Posted by CJ421

*hands over ears* blah blah blah can't hear you!

Man I just can't catch a break ... brake ... I need brakes ... because racecar ...

My mind is just about to go completely.

Good review though. Glad your liking those JRZ's. I think you have a great ride height for a full undertray diffuser system.

[spicish22]

Originally Posted by CJ421

Good to hear coming from you. I have no regrets about keeping the ride height. There is precious little room to lower these cars and maintain the standard geometry.

FYI car is at VAC now for some upgrades - Michelin PSS (235/265), the ETS 5" intercooler, a brake fluid flush, and VAC's beautiful stud kit!

hahaha... thought you were just getting PSS next!

Originally Posted by E90335iflyer

Thank you.

Anyone else? I usually like to see quotes from at least 3 vendors and speak to each before placing my order. Price is not the biggest factor, but customer service is. Had too many experience before going with the best quote but also getting the worst customer service after the purchase!

VAC & Mike are top notch! customer service is excellent. i drive over an hour to go to VAC cause i value having someone i trust work on my car!

[CJ421]

Originally Posted by turugara

Good review though. Glad your liking those JRZ's. I think you have a great ride height for a full undertray diffuser system.

LOL. In my very pleasant daydreams.

Originally Posted by spicish22

hahaha... thought you were just getting PSS next!

VAC & Mike are top notch! customer service is excellent. i drive over an hour to go to VAC cause i value having someone i trust work on my car!

Lol blame Steve.

All parts are installed now, the intercooler is just beautiful. I'm gonna pick up the car later this week when I'm done work.

[Mike@VAC]

Bumpstops: This is a copy/paste from the MAN in Holland.

1. We are not in need of a bumpstop due to our design philosophy. We are always using high compression forces in relation to the rebound forces. We know that that is the way to go (because of years of development and testing, as you know, we win races). So reaching the end of the stroke with a high velocity will almost never happen due to the high compression forces.

2. The high gaspressure also helps with this. We set our dampers with a high gas pressure. When compressing, this force rises. The more you compress the damper, the higher the gas pressure will be as well as the resistance in compression.

3. When you install bump stops you actually insert a extra spring on the end of the stroke. So what happens when you hit the bumpstop is that the spring rate goes up exponentially. The bumpstop will consume this compression force and will give you (almost) the same in rebound force. So the bumpstop throws you back up. When you are cornering and for some reason you are hitting the bump stop, you will first compress the dampers and bump stop. And while you are still cornering, the bump stop throws you back up!!

Having said all this, we’re not in need of a bump stop. We always design our dampers to work superbly without any need of a bumpstop. That is the way to go. You can find a solution for a problem, but it’s better to resolve the problem so it doesn’t occur anymore.

[Andrew@ActiveAutowerke]

We are installing the JRZ RS pro's on our shop car right now! I can't wait to take her for a spin

[rismo]

Originally Posted by Andrew@ActiveAutowerke

We are installing the JRZ RS pro's on our shop car right now! I can't wait to take her for a spin

How is your impression of the kit? What springs go along with the pro set?

I'm seriously considering the RS1's....