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Old 09-10-2007 | 06:37 PM
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i have 2 sets of kumho 710s 245 and 285
should i keep trying to sell the 245s and run 9.5 all around
or rull staggered 8.5 f and 9.5 r
i currently have 2 track 9.5
i will just be doing open lapping (5-8) and couple (2-3)of auto x events in the next 12 months or so
need advice
thanks
Old 09-11-2007 | 06:04 AM
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a lot of tire guys will tell you for track use its optimal to use same size front and rear. however spend a few mins at the track and look at the faster cars. usually they run 295 or 315 rears and 255 fronts or bigger. i run 245 on all four corners. i also dropped down to a 17 inch stock rim from my factory 18's. figured a little less rotational mass wouldn't hurt.

my thoughts are if you have a high HP car, your going to need more meat in the back. My 245's on my N/A Z rarely slide out. If I over cook a turn or just plain make a mistake sure yeah the azz will slide out some. I can still induce oversteer if needed however with a little left foot braking or lifting at the right/wrong time. Not sure inducing it would be as easy if my car was sitting on huge tires in the back.

I know...i didn't help at all..sorry. just giving ya some thoughts.
Old 09-11-2007 | 07:11 AM
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For cost and tire life the same size all the way around is MUCH better since you can rotate to any corner.
Old 09-11-2007 | 07:38 AM
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Originally Posted by mhoward1
For cost and tire life the same size all the way around is MUCH better since you can rotate to any corner.
+1

I run the same size (255/40/17) all around as well. It really neutralizes the balance of the car. Cost benefit since you can rotate tires.
Old 09-11-2007 | 08:16 AM
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given what you guys said
i am still na
springs / sways done
are the 285 on 18 all around too much ?
the motor will stay na for as long as its a track car
flywheel is next with exhaust and kenetix plenum
no need for more serious hp increase
trying to save cash cause of other hobby expedetures in the last 2 years
thanks for the replys so far
what do ya think

Last edited by gixracer; 09-11-2007 at 08:19 AM.
Old 09-11-2007 | 09:17 AM
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just keep those tires, run a set of 245 all around and 285 all around and see what difference it makes in time. i run 235s all around and i have no problem. i do wish i have more grip
Old 09-11-2007 | 11:16 AM
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the problem is cash
i wish i had enought for two sets of track wheels
i have two sets of staggereds (tires)
i just need to decide wether
to get 9.5 fronts----one set of 245 to sell and run 285 all around
or
to get 8.5 fronts----have 2 sets of tires and run staggered
Old 09-11-2007 | 11:31 AM
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We race on Kumho 710 285/35 x 18" all around, but are allowed to use 9" front and 10" rear wheels. This combination works well as we set T-2 track records this year at both Nelson Ledges and Roebling Road.

We have on hand a couple of sets of take-offs and will have 3 sets more after the runoffs in mid October. We use a new set of tires for each racing weekend so they dont have a lot of use on them. At the runoffs we will have a new set for each day of qualifying and then pick the best set or fastest set for the actual race. So those other two sets will be only 5 or 6 lap tires. Let me know if anyone wants some. Bob Hines
Old 09-11-2007 | 07:23 PM
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i wish this was going to be easier
the 9.5 wheels do not clear the front brembo calipers. they just barely hit.
yes a 5mm spacer would work
is it worth going and getting the spacer for track use on the 9.5 or am i barking up the wrong tree
the wheels are the raze r74 18x9.5 with 35mm offset (26lbs a wheel)

i am just trying to get the most for what i have 2 wheels(2 more to purchase)and 8 tires (4-245, 4-285). need alitlle direction to get a balanced car on the track

Last edited by gixracer; 09-11-2007 at 07:45 PM.
Old 09-11-2007 | 08:37 PM
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dont worry about it, just drive. I don't know what your driving level is, but your driving should dictate you on how you should go.
Old 09-11-2007 | 11:30 PM
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If you're this new to things, my suggestion would be stay with the stagger. that extra little "safe" understeer could save your butt

I'd avoid spacers.

Also, if buying a set of wheels and/or tires is prohibitively expensive you might wish to reconsider track days, it's an expensive hobby and more addictive than crack, meth and heroin combined... you'll find yourself buying tires / brakes and that the costs of keeping a car safely maintained for the track isn't cheap. Certainly not trying to talk you out of it but just keep in mind the cost.
Old 09-12-2007 | 03:57 AM
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Originally Posted by gixracer
i wish this was going to be easier
the 9.5 wheels do not clear the front brembo calipers. they just barely hit.
yes a 5mm spacer would work
is it worth going and getting the spacer for track use on the 9.5 or am i barking up the wrong tree
the wheels are the raze r74 18x9.5 with 35mm offset (26lbs a wheel)

i am just trying to get the most for what i have 2 wheels(2 more to purchase)and 8 tires (4-245, 4-285). need alitlle direction to get a balanced car on the track

Could always grind that caliper down slightly.
Old 09-12-2007 | 04:17 AM
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after looking at the tire prices i will go with the staggered set up. its kind of a function of cheaper wheel fitment and tire maximization for the time being.

as far as knowing about expenses and addictivenes, i raced motorcycles in ccs for 4 yrs as an expert. that gets spendy 2-3k a weekend, then taught as an instructor for free track time the last 4. my problem is i have too many bikes i don't want to give up and the z is only a temporary track car for the next 2 years or so. when i want to have a dedicated track car it will be a true track/race only car. the z right now is the the fun, go out on a date with the wife no kids car.

right now the goal is to be set up for the alfa day at grattan in october

thanks guys
no spacers, staggered setup is the way for me right now
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Last edited by gixracer; 09-12-2007 at 06:03 AM.




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