Advise on full suspension upgrades
 

hey guys, I want to start a discussion about suspension, bushings, roll bars, control arms, links, etc. I plan on building the ultimate street car, with handling capabilities able to tackle any track. I want to have the ability to adjust every component. I've already decided a brand that I want to have for all my suspension arms, bars, links. The brand I chose was SPL. I want my suspension to be bullet proof. I want to have a good coilovers. I keep coming back to to BC racing DS/DR type coilovers. just because the simple fact that they are digressive and have a pretty good range of adjustability. I'd go full fledge racecar and get the ZR type but, I feel like the higher I go up in performance, the higher chance the drivability on the street is depleted. I don't want to have a track dedicated car, then again I don't it to be street dedicated. I'm torn between solid mounts and poly mounts. any opinions on that? reputable brands? btw I'm going true coilovers in the rear. I know the whole ordeal with the eccentric lockout bolts. whats the best sway bar with the best adjustability? I don't want to have any binding. what's your dream suspension setup? lets start a discussion. all opinions are welcome. im open to all ideas

Spl solid , then poly bushing elsewhere and BC coilovers. I'm sorry but it sounds like an unorganized train wreck.

Spl is awesome , my car had their full parts on it, worth every penny for a track car. I still recommend them for street cars , but without quality dampers , just not worth the price if admission. Spend the money on KW V3 or better coilovers, quality dampers are more important.

Coilovers, differential, front upper arms, front LCA bushings, swaybars and rear subframe bushings are a must. Other parts from there are just nice to have.

It can get very pricey , especially if you are paying for the labor. I have done a bit of what you are talking about , I don't track the car , but for the street , and for being so low, mine drives amazing. You really feel the loss of bushing deflection and also a general feeling of being very smooth , & very stable over OEM....at all speeds . Lastly you can dial in, and maintain great alignment , and enjoy great tire wear.

Stance SS True Coilover
Hotchkis F & R Sway Bar
SPL = V3 FUCA, Ti Rear Toe Links, Ti Rear Traction Arms, Ti Rear Camber Arms, Eccentric Lock Out Kit, Solid Rear Differential Bushings , V5 Front Outer Tie Rod Ends, Front & Rear Sway Bar End Links.
19" Forged Work Wheels 9.5" / 11" , Single Digit Offsets
35 Series Soft Compound Tires

Look at this sticky too, it has most of the info you need, bar subjective stuff like suspension.
https://my350z.com/forum/brakes-and-...ion-101-a.html

I don't like BC Racing, granted it wasn't flagship coilovers I used previously from them.
I'm using MeisteR GT1's (newest valved stuff) and spherical bushings on nearly everything, and another friend here is using some VERY nice MCS suspension (talk to them first if you're serious, with deep pockets):
http://motioncontrolsuspension.com/

Yes it may sound like an unorganized train wreck, prolly just cause I just began planning lol. Why does everyone dislike BC coilovers? The only reason I'm considering poly bushings is because of vibration, I don't care about road noise or nvh. I just feel like if I chose let's say solid diff bushings, and I'm driving on a grooved road surface, it doesn't seem healthy. I just don't want my car to rattle itself to death. Just think of when an engine is being put together and the clearances, vibration is bad and you usually try to stay away and you keep all the clearances in spec. I know the tires and dampers have a lot to do with the vibration being diluted a bit. I don't know where to research all that stuff but I'm looking. I just feel like the research would just be hypothesized and have no data (The pros and cons of solid and urethane individual bushings). With your car, how much did you drive it? Any failures? I'm going to be doing all the work myself because I don't trust shops. I'd rather do it myself. One reason being that it's a good feeling to say that I built my car and I didn't pay someone to do it. The other reason being I won't have anyone to blame but myself if something goes wrong. It's just I know I do quality work and I don't just treat my car like a machine. Yea I don't have a lift but, who cares lol. I think the only thing I'd leave in someones hands is the tuning.
Alright can you give me like a description of what your car felt like mid corner, exit, and straight away? Before and after the upgrade?

You can choose poly if you want but it has terrible stiction/binding (imho). If it's purely rotational (steering rack/sway bars), it's fine as long as it's lubed.
If you use poly on any articulating suspension joints, you turn the steering wheel and there is a delay in response in comparison to rubber or spherical.
You feel it initially react slowly and then suddenly it does what you wanted it to (have a search online, there are some YT videos too).

There are different grades of polyurethane, so I'm sure some 'feel' better than others but I'm not using any again (unless rotational).
If the car is road only, I'd go with oem or I'd try out Hard Race (rubber).

Difference between OEM rubber differential bushings , and solid SPL bushings are not significant where vibration is concerned IMHO. The loss of deflection , increased response , & never having to change them again more than makes up for it.

Heh I have to change a couple, the white nylon inserts (I presume to stop rattle) on a couple have made their way out unfortunately.
Granted it's only to reduce the annoying rattling going on, although the kaaz diff makes enough of a racket out the back anyway :icon38:

I researched a little bit recently, and came up with a somewhat reasonable upgrade. i think I'm going upgrade the sub-frame bushings to solid bushings. i think the only bushing that i will upgrade to poly is going to be the diff bushing. my reasoning behind this is i think that having the diff held down when under high stress loads will cause wear (possibly failure)especially lets say if i hit a bump and my suspension bottoms out, i feel like it would be better to have the diff cushioned than be held down. i don't know if there is a study to this but, i'd really like to see if there are any proven facts to what is better for the drive line. oh yea i was reading up on the compression arm bushings from spl and saw reviews saying there was really bad noise and that there was premature wear on the cones and that the design was flawed. has anyone found a solution to this besides machining the cones down? have they revised the the design at all? im not sure whrre i read this but i recall seeing somewhere that if your car is too low this will happen. any thoughts about the solid bushings from sikky can have any effect on how those spl bushings react? ive heard the bushings raise the frame or something to that affect. and that it lowers the roll center. i have no idea how that has anything to do with each other... just brainstorming.

Regarding the dream setup, I aim to run Koni Yellow shocks, and Swift Spec R springs in the future. This would be ideal for my daily driven, occasionally tracked z. I don't have any aero mods, but I have a Tomei 1.5 way LSD with oem 3.9 final drive on the way. I found a great deal though a Facebook group, and jumped on it. Even comes with a cooler. I'm on 18 x 10.5" RPF1's with Sur4g 275/35, squared setup. Swapped in face-lift breaks that I got a great deal on as well.

I also have Z1 polyurethane trans and engine mounts - they greatly increased driver feel, without really affecting NVH. The Z1 brake cylinder brace, and Bell Race Works diff braces also greatly improve driver feel, and are mods worth looking into.

If the sky's the limit, there's also various Soul Function body braces that look great, and make the car more rigid.

How's the fitment on the rpf1s? Are they +15? Any mods to the body to get them to fit? How flush? Cause that's the exact setup I've been planning on running. Just haven't found anyone that ran 275 square. Could you go any bigger of a sidewall?

I think you have the right idea leaving the diff bushing as poly, as a solid diff bushing will increase the NVH alot. However, you should be fine with solid bushings on the various suspension arms. One of the biggest areas that a solid diff bushing will 'increase' feel that I've read, is the compression arm bushing.

SPL has been regarded as one of the highest quality parts manufacturers, but I will add that I'm happy with my Z1 rear camber arms, with solid bushings and eccentric lockout kits. Be careful choosing the front camber arms, as many of the brands have sub-par design for holding your alignment.

I've read alot of good things about BC coilovers, but who knows if those people used them on a track, etc... Maybe take a look at Fortune auto, read good things with those as well, I don't have personal experience though.

Honestly I noticed mild deflection only when running slicks while hooning the chit out of the car at the track. Under those conditions (with slicks) I'm sure you will notice deflection with spherical bearings as well. I'm running poly bushings BTW (front and rear upper & lower control arms and subframe bushings).

IMO I would work on the driver mod before upgrading the suspension. For most street driven cars poly suspension & subframe bushings, sway bars, and a set of good shocks (Koni yellow or Bilstein) are more than enough to have fun & leave enough for driver improvement. Personally I would avoid the majority of aftermarket springs (except the OEM Nismo 350z springs which are stiffer than stock) because they lower the car & decrease the spring rate :thinking:

IMHO coilovers don't belong on a street car but I know that's not a popular opinion. I've driven cars with solid bushings and just don't want to put up with the amount of noise they put out. I have the nismo s-tune suspension set with a mix of poly and nismo (hard rubber) bushings, whiteline sway bars, spc rear camber arms and kinetix front uppers. I have zero noise, ride is tighter than stock, slight drop, fully functional and actually rides better than stock. It's a win-win for me.

Diff bushings, run solid. Poly have failed do to heat. Subframe bushings, Run the poly ones as you will get little to no deflection in that location.

My car, I ran solid diff and poly subframe for a while, then upgraded to Sikky raised solids.

My G will have all poly as it will never see the track

Yes, +15 with no mods to fit. Keep in mind, I'm on stock suspension, so when I go lower, I'll need to roll the rear fenders. I probably could go bigger on the sidewall, but this setup was recommended by Russ at Z1, who initially hooked me up with the wheels/tires combo. I think the compound is slightly different on the 40's. I also go down to 30 psi on track days - these tires perform great. No rubbing, and terrific grip, I removed a fender liner screw, as it could rub against that. But as far as everything else is concerned, go for it.
https://cimg5.ibsrv.net/gimg/my350z....fc54c21ed5.jpg

Your car looks great man. I appreciate you replying btw. I'm looking forward to getting those rpf1s. Hopefully I can get them in that gunmetal color. the color of my car is carbon silver, so I think that would look great. Your front ride height is perfect, I don't know why Nissan decided to rake the car so much. I'm not sure what all affects the performance of the car when you lower the rear, but I think it looks better lowered. Yea I talked to Russ, he seems like a really knowledgeable guy. He's the one who quoted me on my exhaust and helped me choose a clutch to buy in the future. But anyways, thank you for replying and helping me decide my wheel setup. You're awesome!

Thanks! I agree, the factory staggered setup was terrible. The squared setup has a ton more grip. I'd like to go slightly lower, but only because it's tracked. Otherwise, I'd stay at stock height.

Have you not watched any Best Motoring videos on the Z ?

The rake help with front down force not that our Z really produce any stock. Sasha from onpoint too his to a wind tunnel and they talk about some of the effects on the z. Unfortunately they don't say as much as i wish they did.