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350Z track/road : help me solve my oversteer problem and improve settings

Old 02-09-2016, 07:57 AM
  #41  
terrasmak
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With your wheel size, I would do 275/35-18 all around.
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Old 02-11-2016, 07:55 AM
  #42  
Nabush
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Originally Posted by terrasmak
With your wheel size, I would do 275/35-18 all around.
Yes, i thought about it, but the R888 at 265/35 are in real already 284mm wide (!!)... With the ride height i had (640mm front) , i had to put camber to -3.2° in order they don't rub... Since i lost too much in breaking with this much camber i put it back to -2.5-2.6° . I hope it won't rub or i'll need a fender roll...

I'm a bit afraid that the R888 275/35 would be wider... though i don't know because my rear 275/40 are 279mm in real...

What alignment are you running front and rear with you 285/30 tires ? and which ET and rim width ? Are your fender rolled ?

Thanks
Old 02-11-2016, 08:11 AM
  #43  
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Originally Posted by Nabush
Yes, i thought about it, but the R888 at 265/35 are in real already 284mm wide (!!)... With the ride height i had (640mm front) , i had to put camber to -3.2° in order they don't rub... Since i lost too much in breaking with this much camber i put it back to -2.5-2.6° . I hope it won't rub or i'll need a fender roll...

I'm a bit afraid that the R888 275/35 would be wider... though i don't know because my rear 275/40 are 279mm in real...

What alignment are you running front and rear with you 285/30 tires ? and which ET and rim width ? Are your fender rolled ?

Thanks
I run 10.5 +15 front and rear , 285/35-18 , then -3.3 front camber and -2.2 rear. Rear fenders are rolled, front fenders are slightly hand pulled and have the tabs folded almost flat
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Old 02-12-2016, 04:45 PM
  #44  
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Going square will also help with the brake balance issues you are having with the high camber, and may allow you to run more and retain balance under heavy braking. Pad choices aside.

16mm or .63in is a pretty large difference. Raising it up will help.
Old 02-16-2016, 07:46 PM
  #45  
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Playing with my friends car the past week I learned some stuff. He has a similar setup on his car 12k front and 10k rear, complains of the same problem. His ride height is actually higher than your, very close to mine.

Here is what I gathered, his rear spring is a 7 inch swift in 10k. I removed the spring and checked the suspension travel range it is seamed perfect. It was hard to measure the how much the spring would be compressed at full travel but didn't seem like enough room. I pulled up the charts from swift to see the effective range of spring compression.

I believe he is running into a coil bind problem before his bump stops engage. An 8 inch spring would allow him to have the same ride height but add usable travel before coil bind. I don't have a 10k in 8 inch laying around, but I do have a 12k in 8 inch that will give him even more travel before bind because of less preload. We are going to try it out next time I hit the track with him.
Old 02-16-2016, 10:40 PM
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Just be carefull the first time out, having 12K front and rear it will oversteer much more than it does now.
Old 02-17-2016, 08:32 PM
  #47  
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Originally Posted by 06platinumG
Just be carefull the first time out, having 12K front and rear it will oversteer much more than it does now.
12k front , 12k rear is the same as the Nismo T2 springs. A great starting point, and I doubt is anything like a normal oversteer, it's a snap oversteer problem caused by something
Old 02-18-2016, 09:17 AM
  #48  
BryanH
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Wouldn't you see evidence of coil bind on the paint of the springs?
Old 02-18-2016, 08:02 PM
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Originally Posted by BryanH
Wouldn't you see evidence of coil bind on the paint of the springs?
Good question, I would think so depending on how often and how hard it hits to bind. These springs have not been on the car long. I may mount a camera and try watch the spring when I go to the track with him, maybe even a little street time with a camera could show
Old 02-19-2016, 04:00 AM
  #50  
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Great thread, and nothing to add that others have already said - EXCEPT -
Your car sounds great
Old 02-24-2016, 03:23 AM
  #51  
Nabush
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Thanks for the new comments... 10 kg sound enough for me, since i'm afraid to loose a bit more traction if i go to 12kg springs..

First i want to try my new whiteline antirollbars, but i didn't receive them yet (ordered in december!!) cause it seems whiteline is closed on january and end december...or it's plant..
Old 02-24-2016, 03:31 AM
  #52  
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Originally Posted by Nabush
First i want to try my new whiteline antirollbars, but i didn't receive them yet (ordered in december!!) cause it seems whiteline is closed on january and end december...or it's plant..
They look the same as Eibach, so if you're struggling to get them try them, very good reputation
Old 02-24-2016, 09:05 PM
  #53  
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What length rear springs are you running ?
Old 02-27-2016, 12:51 AM
  #54  
Nabush
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Originally Posted by terrasmak
What length rear springs are you running ?
I really don't know... They are the standard 10 kg rear springs from BC Racing ER Coilovers...

Speaking of that i find it very difficult to set up correctly coilovers with separate compression and rebound setting.

I find on the road that 5/30 compression and 15/30 rebound seems good. Last time on the track i put 30/30 on compression and leave 15 on rebound. need to try 30/30 rebound next time to see what it changes....

Another news : just receive my SPL compression bushings, LCA SPL bushings, SPL solid diff mounts and Nismo rear traction arm bushings.

Need to find the motivation to mount all these...it's a shame i didn't receive the whiteline sways bars since i'd like to install these first to see the difference..
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Old 02-27-2016, 08:24 AM
  #55  
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This will help a bit, 2 way coilovers are not simple to set up.
Attached Thumbnails 350Z track/road : help me solve my oversteer problem and improve settings-image.png  
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Old 10-09-2016, 12:56 AM
  #56  
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Nabush, have you fixed your problem with left turn snap oversteer ?

Terra, any news after testing the 8 inch rear springs on your friends car?
Old 07-26-2018, 08:42 AM
  #57  
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For reference I usually track m car with BC ER with around 20-25 compression damping. Rebound damping needs to be sufficient so that in quick left right turns the suspension stays accurate. My car is a bit higher than yours with 1.5 deg rear and 2 front camber. I've bee using oth r888 and michelin PSS. Car handles nicely, but lacks downforce with stock aero. In that video you were in gear when it happened right? So it's not you unsetteling the car with improper heel and toe?
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