AX Tire Question for Boxster
03-07-2006, 02:02 AM
#1
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AX Tire Question for Boxster
My Dad asked me a tire question I couldn't answer. He has a 2000 Boxster with 17s. Currently running 205/50 zr 17 front and 255/40 zr 17 on rear. An AX instructor suggested moving to 225s in the front but he can't find 225/50s in the Yokohama Advan Neova AV07s. They only come in 225/45s. Will this mess up his speedometer / mileage? Should he run a different sidewall or consider a different tire??? Many thanks.
Matt S
Matt S
03-07-2006, 08:41 AM
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Actually, if you are getting dedicated AX tires, 245/40s all around are a good choice. If not dedicated AX tiires then 225/45s will be fine up front.they have worked for me. The idea is to reduce pushing (understeer) this can also be done by increaseing front air pressures. On street tires, I find the going to about 36-38 lbs all around works well. This is just for the AX...I usually run 31F 34R on the street.
You can find out a tires circumferance from the Manufacturer, the idea is to have all at about the same measurement.
You can find out a tires circumferance from the Manufacturer, the idea is to have all at about the same measurement.
03-08-2006, 10:18 PM
#5
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Originally Posted by autobahnNY
225/45 is the size you want up front. This is the size most upgrade to if you have stock 17 inch wheels.
i'd stick with the 255 in the rear, i'm not sure about the guy who mentioned running 245s all around seeing as the front is a 7" rim and definately wont fit a 245 properly!
edit- another note, check out this tire calculator. you'll find a 225/45 is .4% different than 205/50 whereas the 225/50 is 3.1% different. the change in size on the 225 is small enough that your father shouldnt notice any adverse effects.
http://www.miata.net/garage/tirecalc.html
03-09-2006, 08:31 AM
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..245s all around is the preferred dedicated AX setup...NOT street..7" rims work OK in this application.
Believe me I've done it and so have many SCCA solo 2 participants.
Believe me I've done it and so have many SCCA solo 2 participants.
03-09-2006, 09:49 AM
#7
Ironman 140.6
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Dennis is correct. 245's all around on 17's (or 265's all around on 18's) are a popular solution for AX.
However, this is for AX only. I would not suggest this for DE or Street.
However, this is for AX only. I would not suggest this for DE or Street.
