camber,toe,fittment question

[jayliu.jiayu@gamil.com]

i am on the stock suspension

running on

rpf1 17x8 +45 re71r 245 40 17 both front and rear
going to install a camber blot for less tire wearing on the front on the track



here the peek for my front tire after one track day









the number i am hope on alignment

front
-1.5 camber
0 toe
rear
-1.0 camber
0 toe


anyone have the experience with this size setup and some camber

could conform no rubbing issue or anything

[churchx]

For track insufficient camber chosen imho. Due more front camber then stock aignment (of 0 camber front) you'll get less understeer, but insufficient camber for even -track- tire wear. In relation to track/HPDE usually i see something like -3 front/-2.5 rear camber, but of course it can be tire dependent and should be dialed right using temp readings of pyrometer.

[wparsons]

-1.5* isn't going to be anywhere near enough to fully fix that, but it will help slightly. You'll need -3* at a minimum with those tires.

[jayliu.jiayu@gamil.com]

Originally Posted by wparsons

-1.5* isn't going to be anywhere near enough to fully fix that, but it will help slightly. You'll need -3* at a minimum with those tires.

I am still use it for daily can’t running too much camber
I am worried about my off set on the wheel, it may leave me
A very narrow space for me to get camber
Will try -1.5 first, if it not work out for me , may consider
Get a stronger ant-roll bar for front and rear

[NoHaveMSG]

Anti roll bar is not going to help with that. More camber is the only real fix or just live with it.

[wparsons]

I daily drive -3.2*F/-2.5*R, it's 100% fine. Even with a much stiffer sway bar front and rear, you'll still need more camber than -1.5* for track use on those tires, or just keep flipping the tires to get double the life as they wear like that.

[churchx]

Same for me, i also drove with similar track alignment whole year. Some cons of high camber - car has a bit more tendency to follow longitudinal grooves on road, and has slightly less grip in winter (where grip is lost way before lot of sidewall flex happens in cornering). My current choice is doing two "seasonal" realignments, -1.5/-1 for winter, -3/-2.5 for summer, alongside wheel/tire switch to/from winter ones, but IF you intend to drive whole year on same alignment AND if you'll go at least to 5+ trackdays in summer, most even tire wear will happen with track oriented alignment, despite your daily driven mileage being much longer. Choose optimal alignment depending on where and how much wear proportionally happens, not by simple mileage. Track wears tires (and brake pads) way more then daily driving does, 5-8 trackdays will wear 80-100% of thread, while 10-20K km of DD will wear only 5-20% of thread depth. Doing just 1 trackday per year? Then optimal camber will be less. Doing 5 or more? Use more track-oriented (of higher overall negative camber).

[timurrrr]

Consider getting harder compound tires. RE71Rs are known to be too soft for the track. Also, 245/40 might be too flexible for 17x8, which most likely impacts the steering response, and possibly causing even more wear for the edge of the tire. Given that this set is pretty much toast now, try 225/45 next?

[jayliu.jiayu@gamil.com]

Originally Posted by churchx

Same for me, i also drove with similar track alignment whole year. Some cons of high camber - car has a bit more tendency to follow longitudinal grooves on road, and has slightly less grip in winter (where grip is lost way before lot of sidewall flex happens in cornering). My current choice is doing two "seasonal" realignments, -1.5/-1 for winter, -3/-2.5 for summer, alongside wheel/tire switch to/from winter ones, but IF you intend to drive whole year on same alignment AND if you'll go at least to 5+ trackdays in summer, most even tire wear will happen with track oriented alignment, despite your daily driven mileage being much longer. Choose optimal alignment depending on where and how much wear proportionally happens, not by simple mileage. Track wears tires (and brake pads) way more then daily driving does, 5-8 trackdays will wear 80-100% of thread, while 10-20K km of DD will wear only 5-20% of thread depth. Doing just 1 trackday per year? Then optimal camber will be less. Doing 5 or more? Use more track-oriented (of higher overall negative camber).

3-4 track day with 5-6auto x this year
I am not sure my current set up allow me that much camber
Will talk to the alignment guy too see what is my current camber
Most likely should be around 0, since it is stock
Will try -1.5 if then
And see how it goes , still have 2 track day this year
Hopefully it allow me get -1.5 without rubbing.
Camber blot May only give me that much I guess
If the tire still can’t hold
The sway bar will be my next
I am sure that will help

[jayliu.jiayu@gamil.com]

Originally Posted by timurrrr

Consider getting harder compound tires. RE71Rs are known to be too soft for the track. Also, 245/40 might be too flexible for 17x8, which most likely impacts the steering response, and possibly causing even more wear for the edge of the tire. Given that this set is pretty much toast now, try 225/45 next?

I may try the alignment first and see how it goes. It toke me sooo much effort to get this tire size right. Almost nothing change for the suspension component
225 45 is not same radius, and it is not usual tire size, going to be expensive to replace
215 45 17 will around $800 245 40 17 will around $950
May also use chalk on the tire to see what’s going on.
“the old school way”

[churchx]

jayliu.jiayu@gamil.com: for rear you'll need adjustable LCAs for any case. For front .. at stock height camberbolts (SPC 8135+KCA416) at both holes worth ~ -2.3 (if lowered then -2.5), if you add to those camberbolts something like powerflex (PFF69-801G) eccentric bushing, up to -3. For even more, extra camber can be added at top mount, for example eccentric rubber mount by Pedders , or pillowball camberplate. Or you can go right away to camberplates + eg. one camberbolt set.

[timurrrr]

Originally Posted by jayliu.jiayu@gamil.com

225 45 is not same radius, and it is not usual tire size, going to be expensive to replace

Just pointing out that 225/45 is a "classic" tire size on 17x8 wheels among 86 enthusiasts. I wouldn't worry to much about the radius, the difference is minuscule, and some say it actually makes the speedo more precise

[NoHaveMSG]

Originally Posted by jayliu.jiayu@gamil.com

The sway bar will be my next
I am sure that will help

Somebody may correct me on this but a sway bar may make it worse since it will transfer the body roll into the tires more.

[jayliu.jiayu@gamil.com]

Originally Posted by NoHaveMSG

Somebody may correct me on this but a sway bar may make it worse since it will transfer the body roll into the tires more.

i think that is not the case

keep in mind i am on the stock suspension
which mean a lot of body roll
get a strong sway bar will balance the left and right in the corner

from my understanding, it will help reduce the weight loading on out side tire
therefore, it helps reduce the tire wearing in the corner.
[ame]http://www.youtube.com/watch?v=_liGnV3PTiQ[/ame]

correct me if i am wrong