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Discussion Starter #1
With H Stock now having a better PAX Index than STF, is anyone going to change their class? Or is the difference not significant enough to matter? Or do people just not care?

Personally I'm kinda split since with the exception of wheels my planned modifications for next season would allow for H Stock, but finding 16x6.5 wheels is kinda a pain, so I may say screw it and continue to race in STF.

The new Indices for those who haven't seen them
2014 PAX/RTP Index
 

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I ran HS for a few years but am now merging to STF. Lightweight 16x6.5 wheels are scarce but they are out there. I used to run the 16x6.5 Rota Boost wheels pictured below. 15.0 lbs each so not super lightweight but better than oem. With the +1/-1 wheel diameter rule going into effect next year I would run 15x6.5" wheels with a 205/50/15 tire and ditch the 16's all together. That would shave a lot more rotating weight and give you better gearing too.

 

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Discussion Starter #3
Dumb question, but what's the +1/-1 wheel diameter rule? I assume it means I could run 15x6.5 or 17x6.5 if I wanted, but is there more to it?
 

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Dumb question, but what's the +1/-1 wheel diameter rule? I assume it means I could run 15x6.5 or 17x6.5 if I wanted, but is there more to it?

Correct, this +1/-1 rule applies to the new "street" classes which will be replacing stock eventually. So we are talking about H-Street here. Street has the same rules as stock except you must be on street tires and you also can go 1" lower or higher in wheel diameter (not width). Stock offset rules still apply which state the offset on the wheels must be within 1/4" or 6.35mm of the oem wheels.
 

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Discussion Starter #5
Ah thanks for the info. Lots to think about for the coming season. I'm tempted to just stick to 16x6.5 (TireRack has some 12.6 lb Kosei's in that size) for my first full season (only did a half season last year)
 

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Bumping this because the AX season looms. :yes:

My 2010 3s 2.5/6mt came with 17"s. I can see going down an inch as first gear seems tall but 15"? Would 15" fit over the front brakes?

My local SCCA group says I could run anything from 15" through 18" per interpretion of the - + 1 inch rule.
 

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Discussion Starter #7 (Edited)
Unless the brakes are a different size than my 2013 3i, I wouldn't think it would be a problem. The hard part is going to be finding anything wider than 6-6.5 in that size. I actually decided to run 16x7.5 and jumping to STF this year because I think (and discussed with another member in another topic) that the wider width would actually bring me out faster

Besides, I almost never stay in 1st gear beyond the first gate or so, but then again the Skyactive is probably geared differently :)

EDIT: Almost forgot, they have the draft of the 2014 Solo Rules out. Couple of other interesting things in there
 
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