[Flooredsubaru]

Ok i got the Kumho Escta V700 in and mounted ready to run on saturday. What are your guy's tips on Psi to run in them for the race?

 

[Storm]

We're running 33psi all around and then bleeding down to 34 after each run. We also run -2.5* camber up front and a 24mm rear bar.

Start here and see how it feels. Good luck and keep it floored!

 

[Wizard of O.Z.]

45 psi , but the course was a speedy course, was told mine was rolling under at the previous 36 psi setting. I think it depends on what the course layout is like and your driving style. The higher setting did welll for myself.

 

[Boy]

You're running 45 lbs on Victoracers??? That seems way too high. I run similar pressure in my street tires.

 

[Wizard of O.Z.]

Yeah that was what I thought but my fastest time came when i raised it. A guy that been racing for a long time said my tires was rolling under and i need to set them higher for this course.

 

[Boy]

Wow, I'd try the old shoe polish trick and start backing down the pressure. You may be over inflated which will cause a smaller contact patch and shorter (relative term ) lifespan of the tire.

 

[10th Warrior]

from what i've heard, the Kumhos run high. also, running that much pressure in a race tire isn't that strange. i, for example, run 40 all around with my R1s. one other thing, the chalk trick doesn't work on race tires because they're sidewalls are so stiff. i could run my tires at 10psi and not get any rollover. this is not to say that there wouldn't be a noticable difference basically, unless you have a pyrometer (and already have your alignment sorted out), all you can do is go by feel and times. if you're region has T'n'T, then you can experiment there, otherwise, its at the events.

 

[Boy]

If he was rolling over at 36 lbs than the shoe polish would've scuffed. It just seems a little high for any R-compound.

 

[Storm]

45 is pretty high. The Kumhos are gonna roll over no matter what. The sidewalls aren't that stiff. If they feel better for you that high, then by all means, go for it.

We tried ours at 40 and worked or way down to the current 33 to 34psi.

 

[Flooredsubaru]

I ran mine at 34psi and they worked awsome... i got 6 out of 13 i wasn't on the gas as much as i should have been for the last corse. i cam though the finish cones at 65mph and ran most of the course in top of 3rd gear. The corse was a little scarry at that speed i kept thinking if i spin at 65 i'm going to go around a couple of times but the kuhmo's didn't make a sigle sound the whole race so it was smooth and fast i just need to work on the driver and try some more camber in the ft.

:biggest:

 

[Storm]

I ran mine at 34psi and they worked awsome... i got 6 out of 13 i wasn't on the gas as much as i should have been for the last corse. i cam though the finish cones at 65mph and ran most of the course in top of 3rd gear. The corse was a little scarry at that speed i kept thinking if i spin at 65 i'm going to go around a couple of times but the kuhmo's didn't make a sigle sound the whole race so it was smooth and fast i just need to work on the driver and try some more camber in the ft.

:biggest:

If you had 45psi in them...you would have spun for sure!

Since you say they didn't make a sound, I would definately drive them harder. Definately go for as much camber up front as you can.

I loosen the lower 2 strut bolts and heft the whole knuckle assembly inward after maxing out the eccentric bolt. This should give you right around -1* or a touch more. Don't even mess with the toe since it'll go out when you lean the wheels in. You want this to happen.

Try and squeeze the last little bit of camber out by loosening the top strut bolts (up top) and hefting the whole strut assy. in as much as possible.

Opening up the holes in the body *a little* will net you another .25-.5*. Don't go overboard or you'll wind up in DSP or SM. Just enough to stay within the stock sized nuts/washers should do it.

If you still feel like you're pushing, air up the rears until you get the balance you want. Put some toe OUT back there while you're at it. (be careful though)

 

[Flooredsubaru]

I still dont understand how to know if i'm rolling over onto the side walls of the tires what is the best way?

 

[Boy]

Take some white shoe polish (get the liquid type) and place dots every 1/3 or 1/4 of the way around the edge of the tire. You want to make sure there is white on both the edge of the contact patch and the edge of the sidewall. If he shoe polish only wears on the contact patch then you're probably fine, if you get very little wear at all then you're overinflated, if the shoe polish on the sidewall wears then you're rolling over. Best thing to do is (ideally at a test and tune) set the pressure around 40 psi and mark the tires, start backing down pressure until the tires start to roll, then go back up in the same increment until no roll is encountered and viola.

 

[Storm]

I'll add to that, the mark should go fairly far onto the tread surface and sidewall. If you're overinflated, you'll see white still on the tread surface. If you're wearing the white off the 1st .25" of the shoulder, then you're pretty good. Any more than that, or if the actual sidewall is worn clean, then air them up a bit more.

Make you're changes in 4psi increments at first so that a change will be undoubtedly noticable. Fine tune from there in 2psi changes.

Don't forget to note your times along with the amount of roll you have. If it's making for fast times...leave it alone!

 

[Imprezawd]

The reall way is get a pyro meter and run the temps between the inside endge of the tire / the ouside edge and the center. Get this onths Grassroots motorposrts. OItalks all about auto x tire pressure and how to find the perfect setup using temps.

Also u can just spend some oney and get yourself a nice coilover setup w/ camber plates. Or just get some camber plates and have the alienment shop mark -1 -2 -3 Degrees. Trhats what i did. Seems to be the easiest way with out taking uor tire off,. Just a little jacking up the car and loosed 4 bolts on top and slam that baby on over!! :drool:

Thats what i will be doing aug 25th a scca WDCR5 auto solo II!!

 

[Flooredsubaru]

can you run camber plates in stock class?


I already found out i'm not alowed to run my bumper at nationals.

stupid scca :boxer:

Oh well My first rally is in september :biggest:



p.s. as is life...

 

[10th Warrior]

no, camber plates are not legal in stock class.

while tire temps are the best way to finally get the pressures sorted, if you don't have your alignment figured out, that is all the numbers will tell you.

 

[nitrohuffer]

On the skid pad running crappy 215/45-17" 712's the best setup was 44f 41r with rear bar set at 18. It seems high, but that's what worked best on my legacy. This may not be the best for imprezza's that weigh 600lbs less though.

 

[Storm]

Major update!

We did some temp testing with a probe this weekend. Turns out we were way soft in front. My apologies go out to anyone who I suggested to run 34psi up front.

After testing, we found that 44-45front and 34-35rear were the right settings. The car was much more stable in the turns and temps were even across all tires. We're running about -2.5* camber in front and 0 in rear with a 24mm rear bar. YMMV...

Too bad it was a day too late as I dug a hole too deep to get out of for a trophy position! We'll be all set for Topeka.

 

[Flooredsubaru]

well i was running 32 in one of my frounts after my run i checked my tire it droped to 20psi and i ripped a whole lot of tread off my brand new tire i will get a pic up.

next weekend i will try the 44 and 35.

i wish i could run the sway bar though

Erik S.