Not sure, that OD with the width is going to be pushing it. An 18" with that offset and a 285/30-18 would be fine.

Dood, he's one of the top Mazda road racers not some forum Fast & Furious tard


Substantial scrub radius increase FTL :hahano:

^^at what point does the + scrub radius of lower offset rims actually effect the dynamics in an rx8?

Because when he's considering 19" wheels he's obviously only concerned with performance.

Good job

Uhh, ok. Whatever you say Team.

:worship::worship::worship: :worship::worship::worship::worship::worship:

Meh, I'm not tied to 19's... just since the car already has them stock I feel like I should keep them. I would rather have a wider tire tucked further under the car than a narrower tire stuck way out there. There's plenty of room in the wheel well, might as well use it! That being said, I do also want them as close to flush as possible.

I would think the scrub radius change would be negligible unless you were doing mainly track/autocross with the car.... but admittedly, I just want the car to look really good. I am likely going to put a turbo on the car, a set of Moton Club sports and these big wheels. This is just for a daily driver, will only see very occasional track use.

So you think the 285/30/19's are too tall huh? They are the same OD as my stock tires, and that's another goal of mine to keep the speedo working right.

Stock is 225/40/19.

^If you just care about the looks, the car would hit a 100x harder on some well fitting 17's on 18's, at a proper ride height. 285 is too much for a NA rx8 on a track. 10+30 with 265 would sit nicely. The specs you mentioned will be sunken, not flush.

any one has experience with this? going to alignment soon, would like some input. Thanks!

Youre just going to have to play around with it at the shop. We cant give you a number lol. Although 245's stretched on 9.5" will allow you to run less camber if you have a stiff suspension

Yes they have almost the same OD, but a 285 is a LOT wider than a 225.

Is the fenderwell contour square, or does it taper in from it's outer width? You said it was your intention to lower the chassis so the larger the tire OD and width the less room you have to work with. I can't say for sure because this OD is larger than my experience. A 285/30-18 is only 24.8".

Best way to tell is to rig up a 1.25" spacer with the stock wheel tire on one rear corner, put the car on jackstands, unbolt the swaybar endlink, and then jack that corner up to see what it looks like. :dunno:

BTW, I sent you an email asking about the internal parts similarity between the Miata and RX-8 Aisin transmissions several weeks ago. Let me know if you didn't receive it.

I'll take a 19" setup over a 30mm scrub radius increase any day

Apparently better than you realized. :cwm27:


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what size tires can i run on 17x10 +35mm/+25mm without rolling.. i don't want to deal with rolling fenders, but the concave on the 17x10 rims look amazing

It's going to have to be a pretty good stretch for that. Aggressive wheel/unrolled fenders limits you big time on tire. I think the 17x10 +25 needs a little bit of a pull, but definitely fenders rolled, with 245s lol. Hopefully someone that actually has a wheel of that size will give you a better idea.

what about 17x9? +35mm?

Yeah, I know the 285's will be wide - that's why I was thinking the tire would be flush after a roll. I am thinking that +1.25 inches must equal pretty flush? Good idea on mocking it up with a spacer, I will do that.

We have a fender roller, so I can roll them no problem - I don't want to roll and pull them, don't want to change the contour of the car too much. I don't mind running aggressive camber.

The car will be turbo, and it will see the track from time to time.

I was looking at 18" tire sizes, and I would have to go with a 265/40/18 to keep the diameter close, or a 275/35/18, and those sidewalls sound tall to me.

Hate buying wheels not knowing how they will REALLY look on the car, especially when they need to be ordered. Wish I could find a picture of anyone else with those SA67R's to see how they look on the RX8.

Did you send a PM here about the trans? I am a bit behind on my PM's sorry - will check today! The gearboxes share many parts, enough that interchanging them is possible... I don't really remember exactly what transfers, it's been a while since I've been in either.

^17x9 +35 you can run a 255/40/17 and not have rubbing problems.

word thanks man!

I think this will work, but it's close and there seems to be some posts in this thread on both sides.

How will 18x8.5 +30 fit all around with 245/40/18 at stock ride height.

^that will fit no problem w/stock suspension.


w00t w00t for an almost free post :D:

The size that's iffy is the 18x9 +30 with those tires... the 8.5's are an easy fit

The new PF01's max 17" size is 8.5" deep. Anyone know if 255/40/17's will fit properly on a 17x8.5 with 40mm offset. I'm interested in how well the tire will fit on the wheel primarily.

^If you can run a 265 on a 9" wheel competitively than you will be ok running a 255 on a 8.5" wheel. Although I would opt for the 245 instead.

Thanks!

I was wondering will 19x9.5 +25 work for the rears

yes you will need a roll and slight pull pending tire size