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      03-07-2016, 08:52 PM   #23
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Quote:
Originally Posted by AriuSen
Quote:
Originally Posted by Finnegan View Post
Fast hands there buddy! Wow.

Two things:

First: Even 700 pounds in the rear might be a bit much. You might be better off going with lower rates maybe 500/550. Intgr8rs MCS rate differential only shows 50 pounds between the front and the rear.

Second: What sways are you running and what are the settings? Need to know what those are before we start looking at spring rates only.

Great stuff by Rick F.

My experience is that heel toeing on the track is completely different than on the street. That's due to how deep you are in to the brakes, and the generally higher rev you're trying to hit with the match compared to street driving, which means trying to give more throttle then you're probably used to as well. If you drive the Z a lot on the street, you build habits that work real well for heel toeing on public roads. But that doesn't help you much on the track, in fact it actually hurts you, since your habits of been ingrained for the street. All that adds up to simply a need for more track time!

Thanks haha...its from a lot of gokart when I was younger.
Anyway, so I have stock sway bars. I dont plan to get aftermarket sway bar ever....I dont really like them....it makes the car feel more nimble, but I think it always compromise grip.

I only drove the z4 maybe 4 times since I bought it....I dont drive it much...and when I drive on streets, I dont do heel n toe.
With the e92 my heel n toe was much better.....not perfect, but much better....I will have to practice more....I am still learning the potential of the car and limits
Gotcha. I'm planning on doing some karting this year myself as a way to ease myself back to the track after about 14 months off.

I really think about those MCS spring rates. See if you can get some more input first, but I don't think there's a reason to go so high in rates.

Another thing, the M is really sensitive to rear toe settings. I'd add some rtab limiters from Turner, and go with toe-in set towards the high end of stock. (Maybe I noted before, sorry if I'm repeating myself.). More here. Integr8, me, Kgolf, my wife--all agree settings toward the "more" side of stock help a bit. http://www.zpost.com/forums/showthre...e#post14527886

If The rear is still getting loose, at that point, you could try disconnecting the rear anti-rollbar. That's another trick a few folks have tried.
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      03-07-2016, 11:02 PM   #24
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Quote:
Originally Posted by Finnegan View Post
Gotcha. I'm planning on doing some karting this year myself as a way to ease myself back to the track after about 14 months off.

I really think about those MCS spring rates. See if you can get some more input first, but I don't think there's a reason to go so high in rates.

Another thing, the M is really sensitive to rear toe settings. I'd add some rtab limiters from Turner, and go with toe-in set towards the high end of stock. (Maybe I noted before, sorry if I'm repeating myself.). More here. Integr8, me, Kgolf, my wife--all agree settings toward the "more" side of stock help a bit. http://www.zpost.com/forums/showthre...e#post14527886

If The rear is still getting loose, at that point, you could try disconnecting the rear anti-rollbar. That's another trick a few folks have tried.
go kart is amazing!!...so much adrenaline....i really love it...but im loving the z more lol

Good info here...I will try to toe settings....I ended up going with 600/700....will see how it feels....I have -3.5 camber and -2.5 on rear...Do I have too much camber?
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      03-08-2016, 12:37 AM   #25
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Quote:
Originally Posted by AriuSen
Quote:
Originally Posted by Finnegan View Post
Gotcha. I'm planning on doing some karting this year myself as a way to ease myself back to the track after about 14 months off.

I really think about those MCS spring rates. See if you can get some more input first, but I don't think there's a reason to go so high in rates.

Another thing, the M is really sensitive to rear toe settings. I'd add some rtab limiters from Turner, and go with toe-in set towards the high end of stock. (Maybe I noted before, sorry if I'm repeating myself.). More here. Integr8, me, Kgolf, my wife--all agree settings toward the "more" side of stock help a bit. http://www.zpost.com/forums/showthre...e#post14527886

If The rear is still getting loose, at that point, you could try disconnecting the rear anti-rollbar. That's another trick a few folks have tried.
go kart is amazing!!...so much adrenaline....i really love it...but im loving the z more lol

Good info here...I will try to toe settings....I ended up going with 600/700....will see how it feels....I have -3.5 camber and -2.5 on rear...Do I have too much camber?
Camber depends on tires, and your driving style. Do you have a pyrometer? That's the only way to know whether settings are optimal. I learned a lot using my 150 dollar gauge. Learn to log and read inner, middle, outer temps. Check. Play with pressure. Then from there adjust suspension settings.

http://www.elephantracing.com/techtopic/tiretemp.htm
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      03-09-2016, 07:32 AM   #26
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Quote:
Originally Posted by Finnegan View Post
Gotcha. I'm planning on doing some karting this year myself as a way to ease myself back to the track after about 14 months off.

I really think about those MCS spring rates. See if you can get some more input first, but I don't think there's a reason to go so high in rates.

Another thing, the M is really sensitive to rear toe settings. I'd add some rtab limiters from Turner, and go with toe-in set towards the high end of stock. (Maybe I noted before, sorry if I'm repeating myself.). More here. Integr8, me, Kgolf, my wife--all agree settings toward the "more" side of stock help a bit. http://www.zpost.com/forums/showthre...e#post14527886

If The rear is still getting loose, at that point, you could try disconnecting the rear anti-rollbar. That's another trick a few folks have tried.
Agree completely with this, the rear toe is a critical piece.

I also run with no rear bar. It helped minimize the snap oversteer and smoothed things out as you get on it and work in throttle steer.

& to clarify I'm running the middle configuration from MCS (100 lbs differential)
I'm VERY happy with this setup.
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      03-09-2016, 01:57 PM   #27
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Quote:
Originally Posted by inTgr8r View Post
Agree completely with this, the rear toe is a critical piece.

I also run with no rear bar. It helped minimize the snap oversteer and smoothed things out as you get on it and work in throttle steer.

& to clarify I'm running the middle configuration from MCS (100 lbs differential)
I'm VERY happy with this setup.
so did you feel a lot of difference going with max toe in?

how were you tires after?

I ended up going with 600/700 =) if i dont like it, ill just orer 750 for rear later.
But I went with eibach cuz price was cheap....are they all same thing? Or hyperco is better than eibach? Cant see springs doing a major difference between brands
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      03-09-2016, 02:32 PM   #28
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Like others have said your way too loose for such stiff springs in the rear. These guys that are running without sways in the rear have actually figure that out.
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      03-09-2016, 03:15 PM   #29
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Quote:
Originally Posted by AriuSen View Post
so did you feel a lot of difference going with max toe in?

how were you tires after?

I ended up going with 600/700 =) if i dont like it, ill just orer 750 for rear later.
But I went with eibach cuz price was cheap....are they all same thing? Or hyperco is better than eibach? Cant see springs doing a major difference between brands
Yes, with 1/8th toe the rear stays hooked up better.
Tire wear was not a problem for me.

IMO hyperco and swift are worth the cost. (Tons of info on the web)
Also Hyperco has a 5.5" spring for the rear which I feel is the ideal length.
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      03-10-2016, 03:28 PM   #30
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And here I am thinking the 500/600 GC setup I've had for the past 5 years is too aggressive...
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      03-11-2016, 12:34 PM   #31
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Quote:
Originally Posted by Caddyshk
And here I am thinking the 500/600 GC setup I've had for the past 5 years is too aggressive...
Haha...... It was a good car control lesson! You should try same rates! Haha
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      03-21-2016, 02:57 PM   #32
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So I went to Chuckwalla this past weekend with 600/700 springs. Car felt much much better. Since it was the first time at this track, I was a little bit lost on braking point, so I was lifting a lot the throttle in middle of the turn causing the car to oversteer. Also this track is in the middle of the desert, so everybody was having hard time getting grip since a lot of sand on the track
Most of the oversteer were from my mistakes this time. I noticed that I have to run very soft compression.
Anyway had fun in the bimmer challenge event!! socal people should join....good prizes!


Last edited by AriuSen; 03-21-2016 at 03:05 PM..
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      03-21-2016, 03:12 PM   #33
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by the way, this time i had 18x10 et 35 square with 10mm spacer on front on 275/35/18 nt01 and I have no rubbing at all!

my compression settings +4/+5
rebound +13/+14
Tried about 5 different settings, and this felt the best and fastest.
Its amazing how 1 click on jrz makes so much difference
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      03-21-2016, 03:32 PM   #34
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Still looks twitchy compared to some of the cars you were following. Fun but twitchy.
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      03-21-2016, 03:41 PM   #35
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my car is so planted to compared to what I'm seeing in this video.... something seems amiss imo, unless the sand really has that much effect ( I'm unsure so take your word on that).
Really good driving however , well done and the car sounds gorgeous!!
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      03-21-2016, 03:55 PM   #36
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Still looks twitchy compared to some of the cars you were following. Fun but twitchy.
thats because you saw all the moments i had to counter. overall thats a collection from 40 laps.
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      03-21-2016, 04:04 PM   #37
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my car is so planted to compared to what I'm seeing in this video.... something seems amiss imo, unless the sand really has that much effect ( I'm unsure so take your word on that).
Really good driving however , well done and the car sounds gorgeous!!
yea...my car is not good yet....i was trying and trying different settings, but I am lazy on going out of the track every 1 or 2 laps just to change compression since I have to lay down on the floor lol.

But at the end, I think figured what I have to do....my compression is still high....will lower 1 click next track....Also I didnt bother adjusting too much, because I dont know this track, so I couldnt have a base line to know whats good or bad.

Also I had 1/16 toe in in the rear....will try 1/8 this time.
But all my friends with e46 and s2k were complaining that it was too slippery too.
thank you for your compliment
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      03-21-2016, 09:22 PM   #38
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Wow, looks like you were working hard on some of those corners mate.
Very well done, loving the laps.
More vids required

Glad you had fun out there
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      03-21-2016, 09:29 PM   #39
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AriuSen,

Looks like you had a lot of fun--and you've definitely got loads of car control at this point!

All the same, it still looks like too much rear roll stiffness compared to the front. You were getting a lot of oversteer both with power and with trailing throttle entering the turns. The second half of your video looked smoother and better balanced--either because the sand had been cleared off the track or because your throttle application was smoother.

If it were me, I'd try a lower rear spring rate. Also, how are your rear suspension bushings? A sixteenth inch of static rear toe-in could turn into some toe-out if the bushings are worn and deflect a bunch. Just a thought.

Keep tuning and having fun!

Rick F.

PS--One other thought: This was a former drift car, right? Could the previous owner have made any other changes designed to encourage a ton of oversteer? Like a very stiff rear sway bar compared to the front? Or different suspension geometry? (The latter would probably require changes to the suspension pickup points, which would be pretty obvious.)
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      03-22-2016, 07:44 AM   #40
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Quote:
Originally Posted by AriuSen View Post

Also I had 1/16 toe in in the rear....will try 1/8 this time.
But all my friends with e46 and s2k were complaining that it was too slippery too.
thank you for your compliment
I assume your rear toe 1/16 per side?
If so then yes definitely bump it to 1/8.

Did you try it w/o the rear bar?

Please note, that with my settings I'm also running a wing.
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      03-22-2016, 10:39 AM   #41
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Quote:
Originally Posted by inTgr8r View Post
I assume your rear toe 1/16 per side?
If so then yes definitely bump it to 1/8.

Did you try it w/o the rear bar?

Please note, that with my settings I'm also running a wing.
hmm forgot that huge detail...i dont have a wing.

Yea i will try 1/8 this time....I run oem sway bars...did you mean to disconnect rear oem bar?
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      03-22-2016, 10:48 AM   #42
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Quote:
Originally Posted by Rick F. View Post
AriuSen,

Looks like you had a lot of fun--and you've definitely got loads of car control at this point!

All the same, it still looks like too much rear roll stiffness compared to the front. You were getting a lot of oversteer both with power and with trailing throttle entering the turns. The second half of your video looked smoother and better balanced--either because the sand had been cleared off the track or because your throttle application was smoother.

If it were me, I'd try a lower rear spring rate. Also, how are your rear suspension bushings? A sixteenth inch of static rear toe-in could turn into some toe-out if the bushings are worn and deflect a bunch. Just a thought.

Keep tuning and having fun!

Rick F.

PS--One other thought: This was a former drift car, right? Could the previous owner have made any other changes designed to encourage a ton of oversteer? Like a very stiff rear sway bar compared to the front? Or different suspension geometry? (The latter would probably require changes to the suspension pickup points, which would be pretty obvious.)
I really love your comments rick, please keep commenting lol.
About the bushings, The upper arm and trailing arm are solid bushings from turner.
and also have FCAB from superflex.
I am starting to beleive that solid bushing in the rear is helping the car oversteer more.....even though last owner build it for drift, all he did was install that drift ebrake and he didnt even do drifting lol
This saturday I am going with 1/8 toe in and also I will try a setting that will be good....if those doesnt work, I will change my spring rates again.
And even then, nothing works, I will have to bring you or someone else who owns a z4m to drive my car and see if my car is normal or if the driver (me) is not driving it properly lolol.

Funny how I drove an e46 after and I did 1 second faster....and that was all because I could go on gas much earlier on corner exit than my z4m. If I can just solve my corner exit oversteer, my car can be a monster!
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      03-22-2016, 11:15 AM   #43
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just few things to note for those interested.
I drove my z4m with nt01 and also my friends e46 m3 with same mods pretty much with re71r
ok....the re71r is definetly not a street tire....its like a super r-comp....I thought that would be good for only 1 or 2 laps, but all 4 laps i did similar time. They are absolutely amazing.
another thing I noticed is that, now I might know why people say m3 are better and faster than z4m......the m3 is much easier to drive fast IMO I did 1 second faster than on my car because moving from a z4m, which is harder, to a m3, took me only 2 laps to get used to it, ....HOWEVER, with the m3 I felt that I was close to the limit already.
With the z4m, my car is not yet dialed perfectly and I did only 1 second slower, which made me think that if I can adjust my car to be close to the m3, the z4m is clearly faster, because I didnt even push it close to the limit yet worrying too much of the oversteer at corner exit.

Last edited by AriuSen; 03-23-2016 at 12:59 AM..
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      03-22-2016, 11:22 AM   #44
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Alex, did you notice any diff with the Epic tune installed? Hows the car running aside from the suspension setup? watching your vid showed your gauges turning from white to blue to red every now and then. very, very cool!
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