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      08-15-2022, 11:21 PM   #23
hC1001
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Do rear toe links and the lock out plate. The stock design has a lot of give to them when you are working the rear suspension hard. It will help or at least keep the rear a little more predictible.
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      08-16-2022, 02:29 AM   #24
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Do rear toe links and the lock out plate. The stock design has a lot of give to them when you are working the rear suspension hard. It will help or at least keep the rear a little more predictible.
That would be my next step. Maybe its my mind being biased but with both zcp bars car feels a bit more planted now. Havent pushed it hard yet but the dynamics have improved a bit from what i can tell. Rear SPL toe arms will be next after i get the gts and cs coding.
Anyone have a good source where to get that done?
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      08-16-2022, 06:26 AM   #25
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Imo, our platform suffers from understeer, not oversteer. This is why most track folks go to great lengths to fit the widest possible front tire, even downsizing the rear tire width in order to run a square setup.

What you perceive as oversteer could simply be a nasty driving habit like overslowing into a corner and then over compensating by getting on throttle too early on corner exit. I see this often and have been guilty myself. Maybe ask an instructor for a ride along for a session before you start modding any more?

On the other hand, the miss matched front/rear tires compounds, springs and Swaybar could be culprit.
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      08-16-2022, 11:46 AM   #26
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Quote:
Originally Posted by D_SheerDrivingPleasure View Post
Imo, our platform suffers from understeer, not oversteer. This is why most track folks go to great lengths to fit the widest possible front tire, even downsizing the rear tire width in order to run a square setup.

What you perceive as oversteer could simply be a nasty driving habit like overslowing into a corner and then over compensating by getting on throttle too early on corner exit. I see this often and have been guilty myself. Maybe ask an instructor for a ride along for a session before you start modding any more?

On the other hand, the miss matched front/rear tires compounds, springs and Swaybar could be culprit.
Well I wouldn't get oversteer when slowing into a corner. It would be from going into one at speed or applying some throttle throughout the corner. My springs are all part of the set. Rear zcp seay bar with base front is what came on CS models but just upgraded the front as well. Tires are different front to rear yes. Maybe it is the culprit.
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      08-16-2022, 11:47 AM   #27
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Quote:
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Originally Posted by David0ff View Post
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Problem is your rear tire compound.

The vette ZP cup 2 is a super sticky, fast warming co pound. The rear connect is a more tamed down version of it which does not have the same ultimate grip and warmup characteristics.

Try looking for a 305 or 315 in 19" from a mustang 350r or GT.
The mustang 305 is as wide as the vette 285.
Suggest the 315 to match your front.
Compound and warmup is almost identical to the vette tire

How I know: I spent last season tearing Cup2s on my lapping car, I delaminated about 12, tried about 20 in all.

Good luck
The one that i got for rear was from a mustang gt350. Not sure if r or not. I think its from the R. The guy said he got the performance set of wheels and this one was from the front. Its the 180 thread wear and not the newer 240. It actually is the track connect version and not just the connect one. Is this the correct gt350r tire that your talking about?
Pics of what i have
This is a pic of 8/20 tires from last season

The top 4 are 285zp vette like yours
The bottom are 305 98y mustang like you need, there is also a 315 which comes on some mustangs which looks like the 305s & 285zp

The 305 you now have in the rear is a tamed down version of the sticky 305 98y which comes on the mustang 350r I'm quite sure
Just double checked and mine is the 102y version but 180 tw. What tw is the 98y?
98y is the one like in my pic is also a 180 I believe, but almost semi slick.
102y like on the proche is like the one you have… it's different, both compound and sidewall.

I assure you the problem you are experiencing is the rear tire.

That 102y 305 only works well on Porsche, I never liked It on my m4 on track, always weirdC always loose and tricky
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      08-16-2022, 11:55 AM   #28
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I see the difference. Then outer thread block has less cut outs on yours and the first grove looks shallower and thinner. I have not ran into the ones that you have yet. Can you post a link to that tire? Does it work well with the zp fronts?
This is tire rack 98y
Picture is wrong

https://m.tirerack.com/tires/Spec.js...tnum=03YR9PSC2

But it's the correct on as starting thread is 5.5/32

The 102 is ~7
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      08-16-2022, 12:19 PM   #29
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Well I wouldn't get oversteer when slowing into a corner. It would be from going into one at speed or applying some throttle throughout the corner. My springs are all part of the set. Rear zcp seay bar with base front is what came on CS models but just upgraded the front as well. Tires are different front to rear yes. Maybe it is the culprit.
I'm with D_SheerDrivingPleasure - depending on how serious you are at the track you'll need to satisfy a few requirements to make proper adjustments on corner behavior:

A) Adjustable Suspension
B) Proper Tire Grip
C) Aero

A lot of the smaller mods you can do will generally throw balance off on the car and make it less predictable. Imo, predictability of the F8X on a track is one of the platforms shining highlights.

Without making any modifications: Corner exit will be throttle control given whatever aero/mechanical grip you have available. For entry, realistically you need to brake earlier and balance the car before smoothly applying steering input.

The car definitely lacks rear downforce and stock suspension has a ton of body roll.

When your car is ready to accept changes your primary goal for corner entry will be more front end stiffness (springs/sway bar) + adjust rear for more rebound + more angle of attack on wing.

Come join us on the track forum - tons of great info and great drivers there.
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      08-16-2022, 01:04 PM   #30
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Quote:
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I see the difference. Then outer thread block has less cut outs on yours and the first grove looks shallower and thinner. I have not ran into the ones that you have yet. Can you post a link to that tire? Does it work well with the zp fronts?
This is tire rack 98y
Picture is wrong

https://m.tirerack.com/tires/Spec.js...tnum=03YR9PSC2

But it's the correct on as starting thread is 5.5/32

The 102 is ~7
Thanks for explaining and the links. It makes a lot of sense now. Would you say the front ZP and rear 98y cup2 are from same compound or very similar?
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      08-16-2022, 01:07 PM   #31
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Quote:
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Quote:
Originally Posted by David0ff View Post
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Originally Posted by Skiy View Post
I see the difference. Then outer thread block has less cut outs on yours and the first grove looks shallower and thinner. I have not ran into the ones that you have yet. Can you post a link to that tire? Does it work well with the zp fronts?
This is tire rack 98y
Picture is wrong

https://m.tirerack.com/tires/Spec.js...tnum=03YR9PSC2

But it's the correct on as starting thread is 5.5/32

The 102 is ~7
Thanks for explaining and the links. It makes a lot of sense now. Would you say the front ZP and rear 98y cup2 are from same compound or very similar?
Yes, same animal, can be paired together great.

I used them both on track, grip the same, feel the same and die the same way.

Tried 285f 305r to start then ended up 305 square after destroying all 4 x 285s.
You will see the 285zp is as wide as the 305 98y
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      08-16-2022, 03:24 PM   #32
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Quote:
Originally Posted by David0ff View Post
Yes, same animal, can be paired together great.

I used them both on track, grip the same, feel the same and die the same way.

Tried 285f 305r to start then ended up 305 square after destroying all 4 x 285s.
You will see the 285zp is as wide as the 305 98y
i am seeing thread width shows 11.2 for the 285 zp and 11 for the 305 98y. wow thats a surprise. What about the 315/30/19 100y from the mustangs, will it fit my 19x11 wheel? I found a used set that I'm tempted to try
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      08-16-2022, 03:27 PM   #33
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Quote:
Originally Posted by David0ff View Post
Yes, same animal, can be paired together great.

I used them both on track, grip the same, feel the same and die the same way.

Tried 285f 305r to start then ended up 305 square after destroying all 4 x 285s.
You will see the 285zp is as wide as the 305 98y
whats your front tire width and et?
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      08-16-2022, 03:31 PM   #34
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Quote:
Originally Posted by Skiy View Post
Quote:
Originally Posted by David0ff View Post
Yes, same animal, can be paired together great.

I used them both on track, grip the same, feel the same and die the same way.

Tried 285f 305r to start then ended up 305 square after destroying all 4 x 285s.
You will see the 285zp is as wide as the 305 98y
i am seeing thread width shows 11.2 for the 285 zp and 11 for the 305 98y. wow thats a surprise. What about the 315/30/19 100y from the mustangs, will it fit my 19x11 wheel? I found a used set that I'm tempted to try
Yes get the 315 instead of 305
Will be perfect on 11

I have Apex sm10 10"&11" wide, et 25F & 44R plus 12mmF spacers & 7.5mmR spacers

Here is a pic of my car with the 285zp F and 305(98y) R
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      08-16-2022, 03:49 PM   #35
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beautiful, thank you!
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      08-17-2022, 11:53 AM   #36
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What improved my rear grip the most is running double staggered setup like the CS. My F82 MY20 763m wheels. 19inch 255 / 20inch 285. On MP Has springs. Tires PS4S BMW Star.

The offset with the double stag really helps the car to rotate a lot smoother and faster.
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      08-17-2022, 06:41 PM   #37
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Quote:
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What improved my rear grip the most is running double staggered setup like the CS. My F82 MY20 763m wheels. 19inch 255 / 20inch 285. On MP Has springs. Tires PS4S BMW Star.

The offset with the double stag really helps the car to rotate a lot smoother and faster.
Stagger in diameter is just looks. Also there may be better tire options in 19s than 20s. Your width stagger is almost same as OEM F8x so you'll understeer bit because of your front width.
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      08-18-2022, 06:30 AM   #38
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Quote:
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Its tuned and a manual. I stiffened the rear because i was getting a lot of understeer on stock tire sizes, i guess i improved it more then i thought it would as its not that much thicker of a bar.
Ok. I would work more with spring rates for balance than change the stabiliser bars. Stiffer bars makes the car more unstable over curbs and puts the car easier out of balance. The rear stabiliser bar does not have that much of effect for stability as it's mostly there to avoid droop but i still see no reason to change it.

Last edited by M 4 FUN; 08-18-2022 at 06:41 AM..
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      08-18-2022, 10:57 PM   #39
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I'm not sure of the M3 dynamics but M4's when pushed hard tend to understeer. Power oversteer can be induced out of corners with too much throttle too early but steady state corning on the limit of traction, we've found they understeer more than oversteer.

On a ZCP M4 street/track setup, this provided the fastest lap times.

MP HAS with camber plates, 3 degrees camber, 2mm toe out CS coded shocks, smaller CS/non ZCP front sway bar.

2 degrees rear camber 2mm toe in. ZCP/CS rear sway bar (stock), GTS coded Diff.

Wheels and tyres, front 19x9.5 ET20 with star spec (GTS) 265/35 Cup2's. Rear 19x11.5 ET45 with Mustang GT350R spec 315/30 Cup2's

Roll Centre is a good adjustment to balance the car and for most tracks, the rear ride height is around half an inch 13mm lower than the front. Raising the front ride and lowering the rear for example induces understeer and vice versa. Here's my M4 in street trim, a bit higher and less front camber.

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Last edited by RevNev; 08-19-2022 at 03:59 AM..
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      09-05-2022, 08:30 PM   #40
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i don't think your stock shocks are alive anymore. even if they are ok this car's stock suspension can't cope in demanding situations. maybe it is time to upgrade for a proper coilover setup and shape the things around it. preferably with something you can setup low/high speed compression and then you have lots of option to play caster,camber,different spring rates.

I am amazed how many f8x owners simply skip the weakest point of the car and try to fix the problem with lots tapes
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      09-06-2022, 01:43 AM   #41
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i don't think your stock shocks are alive anymore. even if they are ok this car's stock suspension can't cope in demanding situations. maybe it is time to upgrade for a proper coilover setup and shape the things around it. preferably with something you can setup low/high speed compression and then you have lots of option to play caster,camber,different spring rates.

I am amazed how many f8x owners simply skip the weakest point of the car and try to fix the problem with lots tapes
I doubt anything is wrong with the shocks. They feel the same they felt since car had 10k miles. And coil-overs cant be electronically adjusted. Its nice to make it softer or firmer with a button
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      09-06-2022, 06:15 PM   #42
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you don't need that button. whichever car i have used with these EDC system (including my current kw ddc - which will be swapped soon ) it felt like only good mode is sport. comfort is bouncy and sport plus rebound too stiff, compression too soft. so always I ended up using sport no matter which condition, car and suspension. (bmws,porsche,mercs)
if you set stiffer low speed and mid stif high speed.

Problem about sway bars, monoballs and rear toe/tractions arms is that you just start to throw random stiffness to the places and I personally could not find a balance and took them off. in one setup i achieved great rear traction however it felt like when it goes out of control, it will go off properly. Then I decided not to throw random stuff and invest in proper coilovers.
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      09-06-2022, 08:05 PM   #43
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you don't need that button. whichever car i have used with these EDC system (including my current kw ddc - which will be swapped soon ) it felt like only good mode is sport. comfort is bouncy and sport plus rebound too stiff, compression too soft. so always I ended up using sport no matter which condition, car and suspension. (bmws,porsche,mercs)
if you set stiffer low speed and mid stif high speed.

Problem about sway bars, monoballs and rear toe/tractions arms is that you just start to throw random stiffness to the places and I personally could not find a balance and took them off. in one setup i achieved great rear traction however it felt like when it goes out of control, it will go off properly. Then I decided not to throw random stuff and invest in proper coilovers.
What coil overs you recommend for f80?
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      09-07-2022, 11:20 AM   #44
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Quote:
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What coil overs you recommend for f80?
MCS has been growing more and more in popularity.

I have never used them but know a lot of very fast F8x drivers that run them as well as some ridiculous E46s. They all seem to love them.
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