sctman1

Everyone seems to run oversize wheels (16's, 17's, and up). I don't want a bigger wheel & rubberband tire.

So, is anyone running oversize 15" tires?
Examples: 195/60-15, 205/60-15, 215/60-15, 185/65-15, 195/65-15, etc, etc.

If not stock, what width 15" wheel are you running?

Handling? (better / worse)

Ride (better / worse)

Rubbing?

Performance changes? (better / worse)

Gas mileage? (better / worse)

The speedometers seem to run a little fast on these anyway & there appears to be plenty of space in the wheelwells to go up a size or two at least.

Thanks,
sctman1

sctman1

No one has stayed with 15" wheels and upgraded to larger tires for increased sidewall height?????

magicmanjk808

i have 195/50/15 but i also have 8" wide wheels. overall height is smaller. probably no help for you, but at least you know people aren't ignoring you. if you need more info on my set up, let me know

sctman1

Thanks for the feedback. I was wondering if I was invisible???????? HAHAHA
I'm considering going to a 6.5" or 7" wide 15" wheel with 185/65 or 195/65 -15 if it won't cause problems. The 185/65 should cause no problems, just a little higher sidewall and overall diameter, 195/65 a little more sidewall, diameter and a little increase in width. Looks like there is plenty of room, would drop the RPM's a little & maybe improve the ride/handling some.
The 185/60-15's just look too small and out of proportion to the vehicle (xB)

magicmanjk808

well, depending on the offset and how low you are, you may have rubbing problems

sctman1

magicman,
The wheel I'm looking at is 15" x 6.5" with +35mm offset per the info on tirerack.com, Stock suspension height, no suspension mods. Do you think I will have any rubbing problems?

magicmanjk808

doubtful.....

Tomas

Yes, there are folks running slightly "oversize" tires on their 6JJx15 OEM or equivalent. There are actually a number of threads on ScionLife discussingh various factors. Here's one: https://www.scionlife.com/forums/viewtopic.php?t=98697.

Search around and you will find several more discussions of oversize tires on xBs.

SmokingTires

I'm running +20 offset I belive with OTG spacers in the rear, with 205/55/15 on a 15x7 rim. I rub slightly on the back passenger side...time to roll the fender. The tires and rims look great. I'm am completely unsure of the offset, I pulled the rims off my e30 bmw. Panasport Ultralights, my MPG has skyrocketed, but mainly due to the larger tires (I'm suspecting) or the fact that the overall wieght is probably 1/2 that of the stocks.

sctman1

Tom,

Thanks for the feedback & link. Your info in the link confirms the outcomes I am looking for (improved ride, stability & slight drop in hiway RPM's) and I too have had very good results / service from BFGoodrich TA's. Seldom snows here in southeastern Va. We do get our fair share of rain but not anything like you get.
I just bought my xB & did some searching in here but it seems like everything I found was discussions on larger wheels & rubberband tires, how "cool" they look even though handling and ride suffers.

Thanks again,
Steve

TomBo

I've been running P205 60 15s on 15" x 6.5" wheels. No problems at all with rub anywhere, totally stock suspension. I notice better handling, better acceleration, (I suspect cuz it is a bit smaller tire diameter thus lowering gear ratio in effect0. I don't know the offset. I want to go a bit wider but not sure where to get the info. on that too.

MileHightC

@TomBo You do realize you just replied to a thread that is over fifteen years old...to a poster who hasn't been on here in almost fifteen years.

MR_LUV

Start with:

Sticky xB 1G, xA Wheel, Tire and Offset Calculator


MR LUV

__________________

04_Toaster

IMO, it's a great first post.......

DannoXYZ

That tyre size is actually 1" taller than stock and lifts your car by 1/2". Width of 205 is pushing it for 6.5" wide wheel. For best handling, you'll want 8" wide rim with that tyre. Pinching wide tyre onto narrow rim actually reduces grip. That's why racing organizations only regulate rim-width, not tyre-width. Wider rims with same size tyre will give better cornering. Do you have any lap-times at racetrack for comparison with factory size tyre of same model? Or instrumented skid-pad testing?*

Proper sized tyre would be 205/55-15 to match factory diameter of 23.75". Next width up is 225/50-15 and best on 9" rim with exact same 38mm factory offset to prevent rubbing on wings. These are pretty close:

https://www.good-win-racing.com/Mazd...t/61-1388.html
https://www.good-win-racing.com/Mazd...t/61-2369.html
https://www.enjukuracing.com/product...oss-black.html

DannoXYZ

* My 1st experience with changing rim-widths occurred at Laguna Seca way back in 1997. My Porsche came with 16x7/8" wheels with 205/55 and 225/50 Pirelli tyres. After year of doing trackdays (about 25) tyres were shot and I decided to squeeze maximum width on factory rims. Spooned on some 245/45-16 Dunlops and eagerly awaited next trackday. By time I finished 4 morning sessions, I was still at same 1:44-1:45 lap times as before with narrower tyres WTF?!@#$!

I asked around with others who were running same car about why phatter tyres weren't improving my times and they asked if I was using factory rims.. yeah so..... They told me that wide tyre squeezed onto narrow rims caused sidewalls to flop around when entering turn and only when outside sidewall was pulled fully to inside, then it started pushing car into corner. But by that time, center is distorted and grip suffers.

So I went looking for wheels. Luckily, another racer at track was selling set of wheels for my car in 16x10.5". AND, they had 12mm more offset than stock to place most of extra width on inside, so no rubbing WOOHOO!!!! Had Dunlop vendor swap my tyres over to new rims and I was ready! On 1st session after lunch, I took it easy 1st lap out and flew off inside of turn-2!!!

Extra rim-width reduced sidewall flop, thus increased turn-in response and grip so much, that my regular steering-input was way more than necessary and car carved tighter turn than needed! WOW! I was amazed at faster turn-in, it made car feel much smaller and lighter; changed directions much easier than before. By time I was done with this session, my laptimes had dropped to 1:40-1:41. By end of day I was in 1:39 range. That's 6-seconds per lap faster than before on exact same tyres! Only difference was extra 2-3" rim-width. In real-world terms, 6-sec/lap at Laguna Seca is over 2 football fields ahead per lap. If I had been racing myself with narrower-rims, I would be pulling ahead by 2 football fields per lap! That's HUGE increase in speed! All from optimising rim-wdiths alone.

Low_Kei

Weird, I run a 205/40zr17 on 17x7 wheels with +35 offset and have no issues at stock height.

DannoXYZ

Factory size of 185/60-15 is about 23.7" in diameter.

Your 205/40-17 tyres are 23.5" in diameter, so pretty close to stock. Good choice on those tyres and wheels with correct offset! 👍🏼

But... his 205/60-15 are 24.7" or 1" taller than stock. Thus raising his car by 1/2" and increasing gearing.

TomBo

No, I didn't. Thanks.

2006ToyBox

My box had TRD 18”x 8” 135/50 (4-100) and the ride was terrible. I purchased Maxxim Ferris with OEM dimensions, including 38 offset and mounted 195/60-R15 tires a few weeks ago.
the ride is so much better, the interior space is quiet and many rattles I was planning to chase are gone. Hope that helps! Good luck