tire pressure & negative camber

[mike13]

All,

I've reviewed the zilvia "archives" (i.e. ran a search) and my concerns haven't been answered directly.

I just got my car back from 2 months of fixing bodywork, and sorting out mechanicals. I had an alignment done. I had the guys adjust my rears to -1.5 camber.

When driving behind my car, You can see daylight where the tire isnt touching the ground from the negative camber. When performing a burnout or powerslide, the tread left on the ground is missing 1/3 of the tire (estimation, dont take these numbers as absolute fact).

Now, i'm inclined to say that with less pressure, the tire will sit flatter on the ground. I usually run ~28psi and up. I dont watch it closely for daily driving.

It's common knowledge that running a lower pressure helps traction on drag launches. Will a lower tire pressure help with overall traction and tire wear?

If so, whats the lowest PSI you would reccomend for daily driving?

[chmercer]

umm, get your camber set at zero if you want the full contact patch in a straight line

[Ian]

lower then 28 is bad for driving on IIRC


i run 35 front and 40 ish rear, but this is for drifting

Daily on my subie i run 32 all around...my tires are still floppy

tread wear is best at around 32-34psi

this is all what i THINK is correct of course, dont take it as fact

[OptionZero]

doesn't it differ from tire to tire?

[Dousan_PG]

you're alignment aint right
i run -1.3 and its all touching. when driving at track and such i get very even wear tad more inside but not by much

i think your camber changed driving around, maxed in
when you put on rucas you kept the stock eccentric bolt right?


i run 32 psi cold
at track might drop it a tad to 35 or so when hot.
235/40/17

[Romeyo07]

yes, but in this case approximate numbers will work fine. Like anything, you have to fine tune it.

[ranisron]

post your alignment spec pittsburgher... perhaps then we can give better advice?

I have set -1.5 all corners, and I have no problems with rubber contacts...

was your toe out of spec? with -1.5 degree in the rear, I have even tire wear. my old tires got eaten away (very fast) from my shitty toe...

EDIT: my tire pressure is usually 32 psi for daily driving. I don't check them that often.

[fuzzy_tanit]

my alighnment is pretty extreme since i attend lots of scca and parking lot acting stupid.

Front
2.5 camber
no toe
7 degree of caster

rear
2.5(way too much but can't change it due to bolt seize so waiting on ruca)
slight toe in (and i mean slightly toe in almost no toe actually)


i use azenis rt215 for daily and track use.
on daily basis the tire gets nowhere near full contact i also run 42psi in an attepmt to wear out the middle as fast as the inside.

on race day i find myself running any where from 37-40psi depend on temp and surface.
with 2.5 camber all the way around i use up almost all of my rear thread (90%) so little less camber would be better for me.
for the front i roll right to the edge where the arrow on the sidewall indicates so perfect match.

with the caster it's and no toe unfront its really reponsive and will "track" to the surface(especially on highway).

i also found what that most favorite setting for drift according to "drift tengoku" mag is
front 2.3 camber, 0 toe, 7 deg caster
rear 2 camber, 2.0mm toe in
(FOR FASTBACK s13)
the coupe uses less camber(2, 1.3) and less toe in 1.5mm.
so try these setting out to see if u like it.
drive in scca to really feel the full limit of ur car and urself.




btw if this post dont make sense is because i havent got ne sleep DAM TESTS
adios

[EchoOfSilence]

why the hell would the coupe have such different settings

[ranisron]

isn't it true that most members on this forum run more negative camber on the front than the rear?

I have -1.5 all four corners, 0 toe all four corners, and 7 to 8 caster for front. What I could say is that ... I need to rework my rear end - shock is really weak now and I don't feel the car to be that stable in lane-change (due to 0 toe??).

[fuzzy_tanit]

why the hell would the coupe have such different settings
i think that it's the different in weight and weight distribution, different in body rigidity. since coupe is lighter and more rigid(dam hatch) you do not need as aggressive alignment as a fastback would.

just an ideal number uras/blitz er34 the 4 door skyline driven by nomuken is set up as
-2, -1.5, and no toe at all but that number is for a fully built car i don't remeber the exact weight of it from one of the option vid but i know that it is most likely to be light than most of our cars due to major diet(glass/windows are heavy).

setting up ur alignment can wary but these are just ideal numbers and recomendations.