what are the optimum 15" wheel specs?

mykflo

Member
After I drop the2.. I want a nice set of beefy tires/rims that will be used for daily driving and autocross about 6 times a year. I'm looking some 6 uls.. rpf 1 s... or " classic" jdm style rims. What's the recommended width/ offset/ any other infohanks
 
Depends.. I guess you want a wheel setup that won't rub when lowered, but how low are you going from stock? 15x7.5 6UL's are wider than by 7's, stick out pretty much as far 15x7 +30 - +35, and will fit a 205/50 tire nicely. Will also fill out a 195 welll.. little bit of stretch, but a little bit of stretch is always good.. NOTE: I said a LITTLE bit of stretch, not hellaflush, stretch and poke type of stretch
 
If you want an autocross setup and plan on running the "standard" 195/50 R1R's then you might as well go with a 15x7.5 6UL or other lightweight wheel with a similar or slightly higher or lower offset depending on your personal tastes. If you want more of a street setup I'd go with the RPF1, Kosei K4R, or other lightweight 15x7 with the 195's. I'm a minimalist in this regard, and figure with a light, sticky, but not too wide setup you can keep weight down, have good grip, and take less of a hit on mpg's. Also a higher offset wheel will be less likely to get scraped on parking curbs (and probably longer wheel bearing life). There are lots of good looking, light, cheap wheels out there too, but of course with those the quality is not quite in the same league. Konig lightspeed comes in a 15x7 and 15x7.5 and may be the best budget lightweight wheeel.

205's can be tempting since there are more options and the prices might even be lower as well since its a more common size.
 
15x7 +25 with 205/50/15

This is what I have for track days same specs. Enkei Rp01's with Kumho victoracers. Just pick a z rated tire that has a high treadwear for a daily driver plus track capability. However you may find that having 2 sets of wheels and tires will be more cost effective in the long run.
 
I like the look of the evil/sema mazda2's. my drop wont be street scraping, looking at just a sporty semi aggressive drop ala h&R/ eibach. 15's are puny, but with the right width and tire, it can be pulled off nicely. Yes i would like to keep it light and my mpg's not to suffer. I was thinking of 15x7.5 6 ul's in nickel. 15x8's and above is overkill? what about tire selection/ offset and those other numbers? any thing else i should be concerned about? I was originally thinking 15x7.. seems neutral ground, but i was reading a lot of mx5 guys who went 7.5 wishing they had gone 8. So my thought changed from 15x7 to 15x7.5 just to give it a little bit more aggression. As far as tires go, i have no idea where to start. Just want them kind of beefy, higher offset, kind of going wider than the wheel.
 
If you are a weight junkie I recommend Konig 15x7 lightning (14 lbs) or 15x7.5 lightspeed (15lbs) both come in multiple colors and are inexpensive.
 
225/45-15 on 15x9's yowza!
 

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If everything goes right, I'm soon to be on 15x9's as well :$.

And yeah, that's extremely light for the Enkei's. One of the reason's that's why it's one of my favourite rim's.
 
225/45-15 on 15x9's yowza!

see what i mean? hotness. so is the 15x9 not doable without rubbing scraping and rolling fenders or what? those are 189 a piece. is it the tire that would be expensive? Oh and those come in at 13lbs each.
 
15x9's are great on a miata with serious suspension mods (STR class), but are overkill on a n/a mazda2. Think of it this way...our cars weigh the same as a miata, but are FWD with less effective suspension and 30-40 less hp. 195/50 on 15x7.5 have already been tested to be the quickest autocross setup. I run 10.8 lb 15x7 kosei's and 195/50's. IMO Kosei (old K1-TS and new K4R) and 6UL seem to be in the sweet spot for quality/weight/price.
 
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Well, my point wasn't made clear enough.. My car is not turning into a street cruiser, since I'll be getting a project car to build up in the nearer future. Out right speed and handling isn't the main priority anymore. Just want the car to look dope.

My project car will be for that purpose though.. my true love is Function > Form (or however makes function the better one).
 
225/45-15 on 15x9's yowza!

see what i mean? hotness. so is the 15x9 not doable without rubbing scraping and rolling fenders or what? those are 189 a piece. is it the tire that would be expensive? Oh and those come in at 13lbs each.

Yeah I like it, Im sure it will work no issues the tires diameter is 22.97 in and width is only .39 in wider than my daily drivers. Mine are way taller and dont rub. This is definately a Miata setup, my friends run these everywhere. However both wheel size and tire size are not as common so prices, choices and availability etc. Here is a visual.
 

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lets get serious now, we really just want that front bumper...
 
Thanks for the info guys. So 15x7 or 7.5 then? So many options.. thought it would be easier.

At first I was going to get 15x7 6ULs, since that's the width CorkSport put on their 2 and I knew it worked, but now I think I'm going with 15x7.5s. Other people here have done it and there's no rubbing at all. You will get an advantage in unsprung weight with the 15x7s, but it's only a few pounds so it's probably not going to make a difference. Added contact patch will probably be more beneficial.
 
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