Jrz rs pro for track
 

How many people run the jrz rs pro? Do you have install pics? I am trying to decide if I need the quick connects to mount the reservoirs so I don't need to get under the car to adjust both settings.

Would like to see pics installed as well if you have them and ideas of spring rates.

Speaking w clintfocus I am going to order two sets probably. 13k front and 10k rear and 14k front and 11k rear thoughts?

Currently run 285/35/18 rs3, would later like to run nt01 and td plus add full aero.

Trust me. Get the quick disconnects. It will make your life easier. Spring rates sound fine (albeit on the soft side IMO), but you are definitely going to want more spring once aero and R-comps come into play. I run just under 18k front and 15.2k rear (1000/850lb) on my autocross car. Not apples to apples since I use very large A6's and have aero. I also don't use a rear sway bar.

not using JRZ's (*jealous*) but I run 18/10k and happy with that. if you have an option for quick changeout of springs, that's prob worth it. how much $?

I'm betting the 10k rear is in coilover....correct? If not, I hope you run a ton of rear bar.

multilink, yes on big bar

I know it's a multi-link, but is the spring on the shock or in the OEM location?

Martin's setup is going to be true coilover in the rear, so the spring rate will be closer to the actual number then in the stock location where its "effectively softer".

I recommended the rates to martin as a starting point, but take into account the socal tracks we run are on the bumper/rough side, so compliance is key.

Sorry being a little off topic here...for you track guys running true type coilovers in the back, have you thought about reinforcing the rear towers? (seems to be somewhat a problem in the E36 3 series)

this is something ive discussed with Martin since its true that the damper towers were not designed for the load of the spring. With his future custom roll bar plans this should be addressed.

How much reinforcement are we talking? Would just the usual endplates on a normal cage setup be sufficient, or do you mean reinforcing all around the top?

FWIW I'm using the JRZ RS1 package that Forged put together (which is JRZ's entry-level - single-adjust without external reservoirs, but they are true coilovers in the rear). Forged's spring setup on those is 11.5k + 9k. Feels pretty nice to me, but the car is still very much at a street level of setup (in that most of the rest of the suspension is stock, and I'm on high-treadwear street tires and no aero mods). I'm guessing I'll ramp up the spring rates later as I add other stuff to match. I run the Hotchkis sways too, lately using the stiffest setting in the rear (but I'd probably back that off a notch or two if I wasn't losing front grip to camber issues...).

reinforcement detail is something best decided by a experience chassis fabricator, which is what im going to do when i look to do such modification myself. Martin is most likely going to go to my guy for the same safety mods and possible rear tower strengthening .

Yeah i recommended the rates to try and get martin back onto his stock rear bar, but to also prep for a rear wing, and 100ish treadware R comps. The high(ish) front rates are to hlep compliment Martin's square setup (18x10.5/285) and the smallish front whiteline sway bar. The 13-14k front ate should work well with Martin's cornering force, and the 370s front weight bias, also the VQ37 motor has some what of a high CG.

We run a much larger split on rates...large front bar.. Small rear bar(in comparison to the front)

The split on spring rates seems awful narrow considering it's in true coil-over. Especially with a big rear bar.

Agree
Just my two cents
we use a 245 front tire... So with a larger front contact patch.. I would seriously reconsider those rates.

when you guys say larger split, Larger higher front rate, or softer rear rate?

I was trying to ease the transition from Martin's mediocre coilover at 10k front 8 k rear. He also has changed alot of bushings, alignment arms etc. Getting him off the stiff rear whiteline bar, off the bump stops, and on a good damper i feel is step one. i dont want to throw too many changes at him at once.

Dwnshift, after testing and speaking with you i like the large front bar on the 370, im leaning on Martin to try the same, but i want to get somewhat of a baseline with these rates.

Thanks for the inputs keep them coming LOL, I need to order ASAP. My whole suspension has been upgrade to SPL, all bushings and every possible SPL link etc.

I currently run whitelines front and rear but like Clint said, I will be playing with other sway bars etc.

Thanks again!

Clintfocus: YES
;)
But more so speaking on the rear

Just chiming in that the split seems very narrow and if I were going to drop JRZ money, I'd get corner weighted and do the math on what spring rates you should actually start with.

As far as rear area reinforcement.. here's what I did:
http://www.the370z.com/attachment.ph...1&d=1375729379

Well we're tracking off-topic a bit now, but... the ends on those bars at the shock towers, are they just welded plates onto the body near the tower top, or is there something deeper going on there? Not that I plan to do any of this myself, but I like to have some idea what I'm talking about when I find someone to do the work.

It's also interesting that your main hoop is just behind that stock low horizontal support part. I've seen pics with it just in front of that, or welded straight onto the top of it for a shorter hoop, but I hadn't ever considered putting it behind like that. Might leave more room for seat/harness mounting/adjustment, too.

so you'd say both, more front rate AND less rear.

I actually have a stiffer front bar in my garage i was going to let martin test on to see how he liked the setup (its inbetween the whiteline and the hotchkis in stiffness)

Again, the rear rate being "high" is in preperation for a large rear wing setup, and to go with a softer rear bar

They're welded through the first layer into the second. There's some sealant between the two layers, we went through that.

The main hoop is in the same position on most of the cages I've seen, I think?

It's where it is on mine out necessity, my seat is within 3 inches of the hoop, as I've got it mounted pretty far back. Idea was to move my weight as far rearward as I could. I may end up needing to re-locate the pedals and wheel a bit rearward, but in the street driving I've done so far with the chair in the current position, it seems okay.

Btw guys, i think the rear tower reinforcement discussion is good and fine in this thread, since most race coilovers for the 370 go to traditional coilover design, the info is relavent

BJ, does conti make you guys run a square setup?

They're 245/275 IIRC.

245/275 Conti DoTs

The conti's don't have the DOT stamp but they are the Hoosier R6 DOT compound, yet a few pounds lighter thanks to a thinner carcass.

The JRZ's have been ordered should arrive in about 2 weeks and if everything goes well they will be tested at Auto Club Speedway on Sept 8th, then on the 14th for Redline Time Attack.

In for details. I'm heading in this direction myself. :D

Hey Martin, I don't know if you have ridden in Len's 350, but I know he runs 15K springs up front on a Moton suspension-not sure what he runs in the rear. He is deployed somewhere in BFE right now but you might be able to facebook him. If you go with 15k's I hope you already have another car for DD or you are gonna break your *** driving through LA.

because of the wishbone suspension motion ratio, the effective spring rate is less then the springs actual rating, also the Z is has a significant amount of weight and grip potential up front so i think the springs in the low to mid teens kg wise isnt bad

Pretty sure Len only runs something like 6-7k spring in back (coil-over). I think anything under 750-800lb spring up front is going too soft.

Len runs 13k front 6k rear as a true coilover.

len who?

Novak.

Don't add aero to cover up something else. You will be quicker with proper spring rates...and no "aero" than a bd choice in spring rates and a large rear wing.
Larger front bar :)

its not band aiding the rates with aero, its in prep for the aero. what good is the rear onces its on the bump stops in high speed cause the rates were too soft for the downforce

Hey dwnshift, can you explain the huge front bar a bit further. I am pretty new to suspensions been chatting with clint a bit and doing my reading. But based on what I sorta kinda know, not totally clear on why you recommend a ton of front bar. Keep in mind I am still 98% stock. Would it be good for me to go super stiff up front? I am thinking of doing sways before dampers and coilovers just to get rid of some of the body roll. In the meantime I am just trying to learn more about suspensions.

If your on the bump stops ...then your rear ride height is too low.
Its a complete package and everything has to work together.

I think he likes the massive bar because the front end of these cars are so heavy, he likes to prevent too much weight transfer to the outside wheel, thus reducing grip.

Big front bar also helps to load the outside rear tire on corner exit as well. My guess is that transfer to the tire is of huge importance on a small 275 rear section width. I also run a large front bar and no rear bar for the same reason. At Road America you don't set fast lap times with speed into the corner, but how quickly you get out of them. Getting on the throttle early onto the long straights is hugely important.