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Old 01-19-2017, 06:37 AM   #1
JayG
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Join Date: Mar 2014
Location: Austin and Palm Springs
Posts: 3,793
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Tire size combo for track

On my 986 S I am doing some suspension upgrades, going to M030 ROW springs/struts with camber plates on the front. For now I will use stock S sway bars. The camber plates will get me to around 2 deg camber Front from < 1 now. Rear camber will be around 2 deg

I am looking at a couple of different tire combinations and wondering what would be the best setup. I have 2 sets of 17" wheels I will be using

Fronts
7 et 55
8 et 50

rears
8.5 et 48
9 et 52

the sets are 7 & 8.5, 8 & 9

I am currently running 225 F & 245 or 255 R
I am looking at 235 F and 245 R as a possibility or 235 F 255 R

The tires diameters are

225/45 25.0 "
235/45 25.4 "

245/45 25.7"
245/40 24.7"
255/40 25.0"

Part of my issue has do do with what class I run in and based on points if I want to change to adjustable sway bars, I can do a 235 / 245 combination. If I stay with fixed sway bars I'm fine with 235 / 255

Am I better off using a smaller or larger diameter rear tire?
I don't have PSM, just regular ABS and in any case the largest difference 25.0 / 25.7 is under 3%

Also, if the new Hankook R-S4 is a good tire choice, they wont be available in 245/45 only 245/40. Short term, I will stay with RE-71R. Later maybe the R-S4s

What is the best combination for track as well as AX?
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Last edited by JayG; 01-19-2017 at 07:19 AM.
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