Jump to content

TT5/ST5 rain tire sizing


Recommended Posts


Hi All,

I am preparing a Mazda RX-8 for TT5/ST5 competition.

200 WHP approximately.  2900 lbs approximately

For dry tires, I will be running 245 R7's on 17x9 wheels (the common setup for other RX8 racers, and confirmed to pass the tire width test).



For rain tires, should I run the same sizes, or should I run a slightly narrower tire and/or wheel? (225's on 17x8 wheels for example)

Link to post
Share on other sites

I'm certainly no expert in the rain, but since there haven't been any replies yet I'll pitch in my two cents.

I think this will depend on the tire you plan on using in the rain. I skimmed through the rules, and it looks like you can use a Hoosier H2O. I assume that's your plan? If so, I'd still get them close to your width limit. They're really soft and actually get warm from my short 15-min TT sessions in the rain. I think you'd want to get them as wide as possible so they're less likely to overheat if it starts drying up in a race.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...