Anyone have any pictures of a rx8 with 19"+ rims on it? I was thinking some 20's would look really nice.

One of the cars featured in the rx8club banner above has 19's.. Keep refreshing the page.

rx8 owners with any aftermarket rims

please post pics in this thread

My only question: why would you want rims (wheels?) bigger than the huge 18's already on it?

After all it's not a "rapper" type vehicle.

next thing you know someone will be asking if you can fit "spinners" on the 8....gheez...out with the ghetto PLEASE!

20's offer no performance characteristics what-so-ever...what would be the point? ah....oh yeh!..NONE!

do you think I can fit some spreewells on the 8?
:p

http://www.urbandictionary.com/define.php?term=spreewells

Originally posted by XeRo
20's offer no performance characteristics what-so-ever...what would be the point? ah....oh yeh!..NONE!

some people like the way they look

Thanks, Mikeb. A lot of people like the way they look....I'm currently sporting 20" chrome Lexani Roma's on my RX-8, and I'm going to go take a picture right now so you all can see what they look like. Why you would want 20" rims is mostly for looks, but those lead pieces of metal the RX-8 comes with weigh MORE than my Lexani 20" chromes (Lexani = 34 lbs., and I think I remember reading the RX-8 wheels are 41.5, correct me if I'm wrong). NOT TO MENTION, with the larger diameter, I'm chalking up miles on my RX-8 at a little bit slower rate than all of you. =)

20" rims DO fit, they fit best with a 245 35 r20, (or if you're daring enough to go w/ a smaller sidewall than a 35, it'd fit better). I put 255's on mine, and it rubs just the slightest bit when the steering wheel's cranked in reverse (doesn't rub going forward cranked). :D

Here's my Lexani 20" Romas. I love 'em. Definitely need some strakes to complement them, though. Anyone sick of theirs? :cool:

The 20' makes the brake look small:(

Originally posted by Landon_Starr
Here's my Lexani 20" Romas. I love 'em. Definitely need some strakes to complement them, though. Anyone sick of theirs? :cool: Wow, that's pretty impressive. So how does she feel and handle compared to stock? Did you drive it long enough with the stock rims to offer an opinion?

The stock 18's are very light, they are quite the opposite of your statement. The exact weight escapes me know but are easily less than the 32lbs you are quoting on the Roma's. Your rims look nice though.

Originally posted by Landon_Starr
Why you would want 20" rims is mostly for looks, but those lead pieces of metal the RX-8 comes with weigh MORE than my Lexani 20" chromes (Lexani = 34 lbs., and I think I remember reading the RX-8 wheels are 41.5, correct me if I'm wrong).

OK, you're wrong - that's for the wheel AND TIRE. The 18" RX-8 wheel by itself is too heavy as you said, and it's around 22 lbs. Your 20" wheel is 50% heavier!!! Enjoy the looks all you want, but talk about heavy slugs!! Unfortunately, while looking good (not my taste, but if you like it, great!), your car will have a worse ride, handle worse, and be slower than a stock-wheeled RX-8. Are the looks really worth all the trade-offs?

Regards,
Gordon

Ok, the weight of the wheels is 10 lbs heavier a piece, I stand corrected (this is why I said correct me if I'm wrong). However, For all these "motor/rotor-heads" in here, if you calculate a 20" wheel with a 35 series tire, you'll realize the overall diameter of the wheel/tire combination is only .15 " larger than the 18" with a 45 series tire......Huge tradeoffs? Not really. Plus I have more rubber on the ground, now, with the 255 vs. 245. I look at it as a wash, better traction, VERY slightly less acceleration.

Handling is awesome, slightly stiffer as you'd expect w/ a 35 series tire, but my treadwear is much better with the Bridgestone RE750's I put on. The TPMS integrated wonderfully (although centrifigul force is slightly less with the wider orbit, so it will turn on at probably 16 mph vs. 12 mph), but it's "sensing" perfectly. All in all, minor price to pay to look different than every other RX-8 owner. =)

Your obsession with the weight of the wheels is interesting. Sure you can shed 10 lbs with a different wheel, but if you go anorexic, bulimic, don't wear pants or shoes, you might be able to shed another 10 lbs!!!!! :)

Sorry, it just cracks me up, it's a street legal vehicle, there will be plenty of mods in the future to compensate for such things. Try to have a little style as you go fast, otherwise buy an old hatchback civic with 13" wheels and slap a turbo on it if looks mean nothing to you. :D

Wow, that's pretty impressive. So how does she feel and handle compared to stock? Did you drive it long enough with the stock rims to offer an opinion? <----------

I put 4000 miles on the stock wheel/tire setup, and really performance difference isn't very noticeable. With the new tires, cornering seems better with the stiffer sidewall, not as much give, but that's about it.

Originally posted by Landon_Starr
Your obsession with the weight of the wheels is interesting. Sure you can shed 10 lbs with a different wheel, but if you go anorexic, bulimic, don't wear pants or shoes, you might be able to shed another 10 lbs!!!!! :)

Sorry, it just cracks me up, it's a street legal vehicle, there will be plenty of mods in the future to compensate for such things. Try to have a little style as you go fast, otherwise buy an old hatchback civic with 13" wheels and slap a turbo on it if looks mean nothing to you. :D

Well, it's not quite an obsession, but you'll find plenty of people who are concerned about keeping unsprung weight to a minimum. Sprung weight (weight supported by the springs, ie anything inside the car) is important, but unsprung weight (wheels, tires, brakes, part of suspension assemblies) actually has a much greater effect on performance - especially rotating sprung weight. It's commonly estimated that additional sprung weight is equivalent to 4 times as much unsprung weight - so adding 48 pounds to the wheels is the same as adding 192 pounds of dead weight inside the car! I doubt you'll be able to trim 200 pounds elsewhere from the car... ;)

Aside from the effect of the weight on acceleration and braking, the effect of increasing unsprung weight is that the ride gets rougher (not just from the shorter/stiffer sidewalls, but from the higher inertia of the wheels, making it much harder for the suspension to work to keep the wheels in contact with the ground over any ripples or bumps in the road surface. This is a street vehicle, right? ;), driven on real roads that aren't perfectly smooth like most race tracks are.

I'm not knocking the look of the wheels, but there are real trade-offs for the style you went for. On a sports car that is supposed to be about performance, it's worth discussing this so that people are aware of the issues. Putting stylin' wheels that you think look great but that reduce performance is a tradeoff that some people might not want to make - at least they should be informed about the tradeoffs. For me, I'd pick lighter wheels rather than heavier wheels over style issues anytime, but that's a personal choice. Hell, I even spent extra on my 17" winter wheels to get lighter ones - I reduced the wheel/tire weight by 6 lbs per wheel compared to the OEM 18"s! I can definitely feel the difference (improvement) from the reduced unsprung weight, and I don't race around or drive at the limit on the streets (especially not on winter tires :D). I guess the other point is that there are plenty of good looking wheels that are also lighter - it's not an either/or proposition.

Regards,
Gordon

Very interesting post. Thanks for the info, Gordon. I may throw the stock wheels back on to see if I can tell a difference, if so, maybe I'll invest in a set that's more lightweight. :D Appreciate the info!!

--L

Wow, very nice ...

tuff ride landon, it looks ill

Any more pics!!!!

Well, it's not quite an obsession, but you'll find plenty of people who are concerned about keeping unsprung weight to a minimum. Sprung weight (weight supported by the springs, ie anything inside the car) is important, but unsprung weight (wheels, tires, brakes, part of suspension assemblies) actually has a much greater effect on performance - especially rotating sprung weight. It's commonly estimated that additional sprung weight is equivalent to 4 times as much unsprung weight - so adding 48 pounds to the wheels is the same as adding 192 pounds of dead weight inside the car! I doubt you'll be able to trim 200 pounds elsewhere from the car...

I think that is overly inflated. I worked it out awhile back and came up with 1 lb of wheel weight is equal to 1.5 lbs of weight in the car when you do a calculation for energy stored in a rotating wheel mass versus a non-rotating mass.

I discussed it a little here:

http://www.rx8club.com/showthread.php?s=&threadid=3681&perpage=15&highlight=weight&pagenumber=2

But I would have to perform the calculation over again since I didn't right it down.

-Mr. Wigggles

Okay,

I recaculated. The kinetic energy of a non-rotational mass experiencing translational movement is:

Kt = 1/2 *mv^2,

where m is mass in Kg and v is velocity in m/s. For a rotating mass experiencing translational movement, the kinetic energy is:

Krt = 1/2 * mv^2 + 1/2 * Iw^2

where I is the moment of inertia and w is the angular velocity in radians per second. For a 18 inch (.4572 meter) wheel that has all of its mass on the outer rim (worstcase), it has an I of:

I = mr^2 = .0523m

and has a angualar velocity of:

w = 2pi * v / (2pi * r) = 3.03v

where r here is the radius of the 26" wide tire. Substituting back in to the earlier equation we have:

Krt = 1/2 * mv^2 + 1/2 *.0523m * (3.03v)^2 = .7398 mv^2

so Krt = .7398/.5 Kt = 1.480 Kt

Or, stated differently the energy needed to accelerate every 1 lb of wheel weight of an 18 inch wheel is equal to 1.48 lbs of payload weight in the car. I don't know where the "4 times" number comes from.

-Mr. Wigggles

Impressive, Wiggles. =) That really helps me feel better about my decision.

Actual facts(formulaic equations, in this instance) are GREATLY appreciated, and we should all take note from Wiggles, post information you KNOW, as opposed to speculate. Pulling numbers out of the air doesn't help anyone, it just misleads.

So, to apply the information:

A 20" wheel exerts 1.48 x weight load of "sprung" weight, so, to compare a 32 lb wheel (mine was 34, but we'll use 10 over just for comprehension reasons) with a 22 lb wheel, there's 40 lbs of "unsprung" weight, multiplied by 1.48, is a total of 59.2 lbs of weight affecting performance.

Granted, as mentioned in previous strings, there may be other adverse handling issues (which I haven't been able to notice between the 18 & 20 in wheel).

Total trade-off equates to 59.2 lbs of weight affecting performance, and minor ( I call them minor since I haven't noticed them ) handling issues.

Thanks again for the information, MrWiggles.

--L

That of course doesn't include tire weight....diameter of a 20" tire is larger, assuming more weight, but the smaller sidewall would compensate a little. I would still assume a 20in 35 series tire would weight a bit more than an 18in 45 series tire, unfortunately I'm not as ambitious as Wiggles to do the calculations......:) plus, specific tires would vary based on rubber composition & structure (additional rubber from rim guards, etc.).

Maybe over-analyzed, but I still found it all helpful.

:)

my dealer has one sitting on his lot with 19" wheels, they are gunmetal colored wheels, i shit you not the car looks completely different and it kicks ass. they are a lighter wheel but he left 45 series tires on it. while i still think it needs a 1" drop the car looks awesome. The wheels are on a black one, he had them on the red demo car and it looked great too. i wish i had some pic to show you guys.

sure you have seen this already. its mine but they are still just 18's. sorry i just thought you might want to see another option of style.

Originally posted by Landon_Starr
Actual facts(formulaic equations, in this instance) are GREATLY appreciated, and we should all take note from Wiggles, post information you KNOW, as opposed to speculate. Pulling numbers out of the air doesn't help anyone, it just misleads.


Good calculations, Wigggles. I must note that this has been debated extensively over at www.miata.net , where some people really do obsess over unsprung weight. With similar calculations, the analysis shows that it depends on how you model the weight distribution - best case is as you calculated (1.5:1), worst case is with all the weight at the wheel and that comes out at around 2:1. Apologies if the 4:1 number doesn't match - it wasn't just speculation or pulled out of the air, I recalled it from other discussions at miata.net. I was just reading another thread on this last night, which revisited the modelling and had the 1.5:1 and 2:1 numbers. However, without comparing those analyses I can't say if the 4:1 is without basis or if that was based on other factors. I'm too lazy to go searching through the Tires and Wheels section at miata.net right now (sad, since I'm a moderator there - maybe I've just read too much of this stuff!)

However - those numbers relate the impact of unsprung weight on overall acceleration (and deceleration), but don't translate to impact of unsprung weight on suspension loads and effects on shock/spring response and tuning. Again, a browse of www.miata.net wheels and tires forum will find a surprising number of owners posting that they went to 16, 17, or 18" wheels a while ago (for style reasons, usually! ;) ) and are now looking to move back to smaller, lighter wheels because of the negative aspects of the heavier wheels on a day-to-day basis.

I'm not meaning to harp on this or criticise anyone's decision, I just wanted to make the point that there are consequences to moving to larger wheels that need to be considered. Landon, I'm not picking on you! Enjoy your wheels and your 8! :cool:

Regards,
Gordon

Your analysis is very helpful, Gord. It was good for me to hear from a performance extremist aspect (maybe too harsh of a term, but used due to a lack of articulation on my part). I have the tendency to take a stronger "style" stance, but it's good for me to hear other perspectives. Thanks for the helpful info, Gord!

--Landon <---handles getting picked on, constructively, well. ;)

I like the black on yellow, JHOUSE, very good looking setup. Complements the vents well. :)

--Landon

Those 20's are awesome man, how much did they run you for all 4 including tires?

I picked up the Roma's from a friend in CA. I was able to get the wheels for 1045.00 shipped (if you're interested I can give you his contact info). Tires are pretty pricey, though, when you're talkin' 20in. My little bro. runs a firestone service center, so I was able to get the 750's at close to cost, which saved me some $$.

Lexani is one of the few brands (when talkin' 20's) that offers the offset necessary on the 8's (I have +45, there has been more in-depth discussion in other threads about the offset). There are a few other brands, but I wanted to show off the disc & calipers, and this style worked well. As stated by someone earlier, it does make the brakes look smaller than I would have liked, but oh well...Now I just need to paint the calipers.

Thanks everyone for the compliments.

--L