Finally found someone local that wants to trade my R83's for his R81's. I want the R81's for auto-x, as they are light, light, LIGHT!

205/50R15 is available in Kumho MX's and Falken Azenis... either should fit, right? According to the specs for each, 5.5 is an approved rim width, and it appears there is plenty of room.

 

Tirerack reccommended that I go 205/55/15, that 50 for aspect ratio wasn't enough. A lot of autocrossers are running it regardless. Hey, it's your call.

 

>>Tirerack reccommended that I go 205/55/15, that 50 for aspect ratio wasn't enough. A lot of autocrossers are running it regardless. Hey, it's your call.

205/50/15 has load if you run 36 psi!

Alex

 

Alex, forgive my ignorance here, but I'd read all across the internet that you couldn't put a 205-section tire on an R81 (something about 195 being the max width for a 5.5" rim....)

 

I look to something like Bridgestone s-03, witch mounts from 5.5 - 7.5 inches.

Results per tire modle may vary.

Alex

>>Alex, forgive my ignorance here, but I'd read all across the internet that you couldn't put a 205-section tire on an R81 (something about 195 being the max width for a 5.5" rim....)

 

Most of the 205's I've seen all have 5.5 - 7.5 as the approved rim widths...

 

Yeah, I've been back and forth on this whole issue...sorry to hijack the thread, but here goes:

I want some autocross tires (I compete in H-Stock in my local SCCA region) but I've been having difficulty justifying a dedicated set of wheels + tires. My dream combo is the Anthracite SSRs 16x6.5 w/Kumho V700's. However, that's ~$1700.

A set of NZO Monzas with Falken Azenis tires (like the combo that Webb Motorsports is selling) is about $1k, and they're good for summer drives, as well. That'll probably be what I end-up with.

If I could grab a set of R82's and put some Kumhos on those in the 205/50R15 width, that'd be close to ideal, but from what I've read that's not a good application: The rule of thumb (from my reaserach) is that the baseline for applications is 185 width is good on a 6-inch-wide rim, and that you vary .5" rim for each 10mm of tire section.

Hence:
175 -> 5.5" rim
185 -> 6" rim
195 -> 6.5" rim
205 -> 7" rim
215 -> 7.5" rim
(etc.)

That's just ideallized, but it does seem like going from 175 to 205 on the same rim is a bit of a strech. I wouldn't have any qualms about a 195 tire, but nobody makes an R-compound in 195/xxR15 to my knowledge.

Anybody have any suggestions?

 

205/50/15 <~~ I yeild any theory I may have to manufature's specified rim widths.

Alex