View Single Post
Old 06-12-2018, 02:09 PM   #15 (permalink)
2011 Nismo#91
A True Z Fanatic
 
2011 Nismo#91's Avatar
 
Join Date: Mar 2011
Location: NJ
Posts: 2,381
Drives: slowly
Rep Power: 33858
2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute2011 Nismo#91 has a reputation beyond repute
Default

Quote:
Originally Posted by Shoeshear View Post
Hey guys, hope you guys don't think I've been cluttering up the forum too much.


Just needed some help on planning out/deciding what to do about suspension. I read the stickies and honestly came away more confused than before I started reading. From sport bikes, I'm somewhat familiar with the adjustable aspect of the dampers (in the sense that I vaguely know what the words mean lol), but when people started to throw shock dyno charts down, I got super lost. The response for true coilovers, non-"true" coilovers, springs, springs and dampers, seemed to be pretty varied and I don't know if the various OPs' question was too vague or just that it's more opinion than fact. I came away with a bunch of weird technical tid-bits, but no real recommendation on which way to proceed.

So this is basically what I understood:

1. For the absolute best, real track performance and lap time reductions, you need a set of really nice dampers with matching spring rate springs to complement the valving from a race-heavy brand (AST, Moton, Penske, etc.)

2. If you don't give a crap, cheaper is better to a degree.

My problem: What the hell do guys who want something in the middle do?
After my first track outing with the Z, a few things are very apparent:

1. The car is extremely capable out of the box and handles very nicely. Definitely beyond my current ability. There are better lap times to be had simply by improving myself.

2. Despite that, I found that the car still squatted and had more brake dive than I'd like, but it cornered pretty flat relative to the amount of front to back springiness. I love the way it takes the corner, less in love with the pitch on brakes and gas.

3. Tires are king.


So now, what do I do if I want to modify it a bit to get what I want performance-wise (a little bit firmer on the brakes and on the gas) but I also desire a slight drop for aesthetic purposes (.5-.75 inches max, don't want much)? I mostly drive on the street (DD), but it will see a couple track days/AutoX every year (as the wallet dictates).

I don't need anything mega adjustable, and something with a minor, but fixed performance benefit would suit me fine. I know that springs can be a reasonable change, but I also don't want the damper to blow out early. I have made this mistake on a previous car and the struts were leaking much sooner than anticipated.

I'd rather just take a little improvement and get better as a driver than get a fancy bit of kit and not be able to do anything with it. And I definitely, DEFINITELY, do not want to make the thing handle worse...

I have run into this situation on my motorcycle. After messing with it and doing all sorts of damping adjustments and getting a suspension guy to look at it, the real improvement just came from riding it.

TLDR: What suspension springs and dampers should I be looking at for reasonable performance improvement, without the need for 3-way adjustability? Is the answer to do nothing? Or just change spring rates?


Please help, you are my only hope.
Suspension is a deep rabbit hole both in dollars and setup. This is why it was the last thing I am doing performance wise to my car. And I'll probably spend the rest of my time trying to figure it out.
I finally got to test my new suspension on the track and it was much better then it was shaved a almost full second off my best right away with the default settings. But getting it setup correctly (I have 14 compression steps x 21 rebound steps = for 294 different settings. Not to mention sway bar settings and spring rate options.) was going to be impossible. I actually hired a driver to put a few sessions in and dial in the correct settings in the pit lane after each few laps. IMO it was worth it because after it I dropped another full second. If it hadn't rained in the afternoon we would have finished what it would have taken me many track days to get even near.

Anyway enough about me, the car will squat and dive on stock springs, even nismo ones. Stiffer springs will fix that but you will lose ride comfort. I have 1000lb/in (17.8kg/mm) front springs and it was/is painful for me especially after the recent harsh winter here in the NJ. On nice pavement it's fine but on concrete roads from 40 years ago with joints ever 25' it makes me want to cry sometimes regardless of how I set the dampers.

#1 Budget is your biggest concern/limiting factor.
#2 Less adjust-ability is more in this instance. Spend more on a better 1-way. And have an easier time learning and tuning it.
#3 Front sway bar. As good as the car may feel in the corners it sure does get it's lean on.
#4 Make a spread sheet of all your potential part options and their prices and pros/cons; make 2 or 3 columns for low cost, middle, and high. Look at it, sleep on it, change it, think about it, then change it again, and after some time you will see one you like more and then go and get it. And after you got it you won't be worried you made a bad decision because you planned and though it through. It took me over a year from start to finish for my suspension overhaul.
#5 Remember you can have plenty of fun with the car as is just by being a better driver.

Edit: IMO I feel the Fortune 500 would be great and make sure you get a dyno sheet with it since each are custom built and tested already.
__________________
GTR TT 493Whp/431lbft, Ecutek, Southbend 6puck,Quaife, RPM RollBar 4Point, R888R, JRZ RSPro F(10R/10C) R(10R/6C) 1000f500r inlbs+150inlbs Tender, SPL everywhere.Full Specs

Last edited by 2011 Nismo#91; 06-12-2018 at 02:48 PM.
2011 Nismo#91 is offline   Reply With Quote