Will It Fit Thread
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.
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.
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.
so I picked up my new rims today. Prodrive GC14i 19 x 9.5 +25 with 245/35/19 all around. Not lowered. Now my question is..I need to run negative chamber for it not to rub, but how low? Will -2.0 in the rear do? I also plan on droping the height.
Right now with 3 ppl in the car and full tank of gas , the rear rubs the fender when going 70 and the road is not smooth. In 30 mins of driving it rubs about 10 times.
Right now with 3 ppl in the car and full tank of gas , the rear rubs the fender when going 70 and the road is not smooth. In 30 mins of driving it rubs about 10 times.
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.
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.
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.

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.
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.
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.
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.
Last edited by J8635621; Nov 2, 2009 at 09:56 AM.
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.
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.
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.
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.
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.

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.





