Page 1 of 1

Rim Size and Offset Questions

Posted: Thu Sep 22, 2016 7:23 pm
by Reitrof
I am looking to change my rim and tire size next year and have been checking this site and am unsure of which tire width and rim width to select.

Current setup

16x8 offset 50 Mazda RX7 rims with 225/50 16.
KW V3 coilovers RX8 sways
Camber is 1.5 in the front and 2.0 in the rear.

Car is a daily driver and I autox about 16 times a year. I also flat tow it behind my RV for 5000 miles each year.

Looking to improve my autox times.

Trying to decide to go with 235 or 245 tires with either a 17x8 or 17x9. Also not sure which offset would be correct, either 45 or 48. I had to do a mild roll the rear fenders for my current setup.

Thank you for any info

Re: Rim Size and Offset Questions

Posted: Fri Sep 23, 2016 8:55 am
by Brian
Lots of detail on fitment on the front page of NC wheel section. My suggestion is look at our 6UL 17x9 wheels and run 235/40 tires because that combo is plug and play....and that is MUCH faster than 16x8 combo you have now, perhaps 3 seconds faster on average autocross course. That 6UL wheel comes in several colors choices on the site, picture below of the Tungsten color on a PRHT like yours.

Brian

Image

Re: Rim Size and Offset Questions

Posted: Sat Sep 24, 2016 8:28 am
by Reitrof
Hi Brian,

Thank you for the reply. Sounds like that's the rim for me.

The tire I want to use, RE-71R's come in 234/45-17, not in 235/40/-17. Will this fit?

Re: Rim Size and Offset Questions

Posted: Sat Sep 24, 2016 10:49 am
by Brian
The 235/45 is too tall...by a lot. In that tire you could use 245/40 and given that you have already rolled fenders it should clear on this 6UL rim.

Brian

Re: Rim Size and Offset Questions

Posted: Tue Sep 27, 2016 6:15 pm
by Reitrof
Brian wrote:The 235/45 is too tall...by a lot. In that tire you could use 245/40 and given that you have already rolled fenders it should clear on this 6UL rim.

Brian
Ok Thanks Brian.