So you think staggered tires/wheels are a great idea?
 

Lots of people here seem to be looking to install wider tires and wider wheels at the back of their RX-8s. We have to assume that they really like the look of wider wheels and tires on the back of a vehicle, but there may also be an impression that staggered tires and wheels somehow must enhance handling? Well, the short answer is - they don't.

There was an excellent article in Sport Compact Car recently where they installed new tires and wheels on their Project 350Z part II - Balance . The 350Z from the factory comes with staggered wheels and tires - and it understeers. To achieve neutral handling and eliminate the understeer, SCC found they had to install the same size tire on the front of the 350Z as the rear, and it greatly improved the handling and balance of the car.

So how does that translate to an RX-8? Easy - if you install wider tires on the back of a stock RX-8 than you have on the front, you will transfer the handling from neutral to understeer. Lots of people will say they only drive on the street and so they don't mind - but if you enjoy the neutral balance, be aware you'll be changing it for the worse if you go staggered.

The article has some interesting comments on tires, wheels, and handling that are relevant to RX-8s and other sports cars - definitely worthwhile reading.

Regards,
Gordon

i will look into that article for there reviews
but my wheels arent going anywhere
see sig :)

Why didn't you just address this to Bassik directly? :) Good info.

Good find,

but in 2 seconds I will forget about it!!!

RX8Power - Staggered

only two reasons for staggered wheels. straight line racing and/or looks.

Do you guys think this setup 225/40/18 front and 255/35/18 rear on 18x8 and 18x9 is ok for the street? This way the wheels have almost the same diameter, but I heard that 255 is too much for the 8...
I'm gonna keep the stock rims (without staggered setup) for track use;) but I don't want to degrade performance much. I like the looks and I don't do street racing.

Anyone has a good advice on what tires to put on these wheels?
Thanks:)

Very good find.. i found it very... STAGGERRING! :cool:

whats staggered mean lol in terms of rims...

For how we are using the term in this thread, staggered refers to the width of the rear tire compared to the front tire. What this means for the rims is that the rear rim will normally need to be wider in the rear for the tire to be wider in the rear. It does not refer to the diameter of the rim or the overall diameter of the tire (not the way we're using the term here).

---jps

Staggering never made sense to me except, as already stated, really just for drag racing.

I've been thinking about this subject recently with the introduction of FI kits. How large should we need to go to accomodate the power? For the 240whp that the Greddy kit provided, I would think 255 or 265 is more than enough to handle that. Anyone have any thoughts?

My thoughts are since people actually have FI kits installed there's no point in theorizing what will and won't work for tires. Just ask them what they have and how it works. I'm sure they have enough incentive to do that research themselves.

WHOA WHOA WHOA,

Not only is the 350z a different car. Guys, they put wider tires on the front not narrower tires on the rear. There is a difference

If a car understeers and your stock tires are 245 front and 275 rear, then going to 275 on front and rear will universally help things. More grip on all corners and less understeer.

That doesn't mean that going to 245's on all corners would give the same results. You are improving the balance but at the cost of less total grip. Taking the argument to the extreme, would 185's on all corners be as good as the stock 245/275 combo? I think most would say no in a heart beat.

The reason I bring this up is that I have 245/40-18's on the front and 275/35-18's on the rear and I love them - and not just for looks. I drive very fast at times of day that have little traffic. I enjoy taking turns as fast as I can. I have no doubts that my new combo (which uses Yokohama dB2 tires) is more stable or at least as stable as stock rubber.

Now if someone told me, "You will get better performance with 275's all the way around." I would probably say yeah you're probably right*. But if someone said, "You should go back 225's all the way around for better grip." I would say not a chance - been there, done that (245's all the way around would be an interesting experiement, but I don't think that would be better either).

The SCC article is hardly an end-all of the debate that will never end. The staggering/no-staggering debate has reach religious proportions. Well I'm an athiest. I go by what I have experienced and what works for me.

-Mr. Wigggles

*275/40-18's wont fit on the front without sticking out or rubbing in some fashion. But for auto-X I would go 275/35-18's all the way around with maybe a little bit wider rubber in the rear. But with a reduced weight load in the rear (1/8th or less of a tank of race gas and all accessory items removed) 275 all the way around would probably be perfect.

Wiggles, since no one answered my question, based on your experience, can you help me with this setup:
I'm thinking 225/40/18 fr and 255/35/18 re will it be ok?

I am currently running KDW 255's on the stock wheels and there is no problem with interference. Wiggles seems to spend a large portion of his post addressing a matter that was not discussed in this thread; going to smaller tires in the rear to achieve better balance. With regard to Gord's post, going smaller in the rear tire size was never mentioned. Going with 4 equal sized tires for better balance was the point. I thought about the staggered look for my own car but decided against it for the reasons discussed here. Since the RX-8 has 50/50 balance I didn't wan't to upset or alter any handling or traction balance by using a staggered set-up. I figured by keeping the equal tire sizes on all 4 corners, as they did from the factory, I would be assured that any driving problems were strictly the fault of the driver. Since I am running an odd-size 255/45 the handling is a bit softer and the turn-in is not as quick but the overall balance is exactly the same. I think that was Gord's point in the first place. BTW, as soon as winter is gone I will be switching to 245/45-18's, still on the stock wheels.

CRH

p.s. RM, your own choice in tire sizes will be fine as long as they are the same diameter. Each manufacturer differs in diameter even though the sizes listed are the same so make sure you look that up first.

p.p.s. Staggering tire sizes, or not, depends on the driver's own style in taking turns.

But it looks mad tyte yo!

Charles Hill is right - my point, and the point of the article, is about balance. Sure, MrWigggles, your car is more stable with the staggered setup - because it's got more understeer. If you want more understeer, then that's a very easy way to get it! The article wasn't talking about ultimate grip (and for MrWigggles again, if you wanted more grip you could have simply put on grippier tires, rather than those Yoko all-seasons. Nice tires, but certainly not at the top of the performance heap).

The RX-8 is very neutral from the factory. Going to 245/40-18s all around is a great way to increase overall grip (assuming you get good max performance tires, of course) while retaining the neutral handling. Going to a staggered setup can increase grip at each end, but not proportionally, so you end up shifting the handling balance to understeer. Who wants more understeer on a sports car? In fact, I'd happily trade a few fractions of a g in grip for better balance - you can't safely corner at the limits of traction on public roads anyway, and you can enjoy neutral balance a lot more often. But again, as Charles points out, you can have your cake and eat it too, just fit same-size tires of max performance type all around.

Read that SCC article again - not how they specifically mention bucking the popular trend of using staggered sizes, and that going to same-size tires all around cured the 350Z's terminal understeer and vastly improved the handling. RX-8s already have that neutral handling they fought to achieve - why convert the RX-8 to 350Z-style terminal understeer just for the sake of trendy looks?

It comes down to whether you want a sports car or a cruiser for posing... ;)

Regards,
Gordon

I couldnt stand the thought of MORE understeer in this car. :( I'd only resort to staggered if I added so much power to the car required the extra rear-grip. Apart from that, It's not required.

How's your alignment? I had mine done last spring, and I found that it was sorely lacking in front camber. Had it reset to some nice numbers (I think I posted them here), and it was much more neutral and balanced. You probably know not to just show up and ask for "an alignment", but to get the exact numbers you want, and ask for a precision alignment to exactly the specs you give them. Also, for best results it's necessary to sit in the car or have it weighted as you normally drive it - it makes a significant difference to the camber results, especially on the right rear corner!

Regards,
Gordon

Gord, can you publish those numbers again, please? I'll be hitting Road Atlanta in March with my new turbo setup and I'd like to have some killer adjustments going. Thx. Are those specs street-drivable?

CRH

Gord,

Actually I want to get from point A to point B as fast as possible. That is my goal and think most people's goal.

You failed to mention in your first post that they made front tires bigger to match backs - ie. big/big on front/back is better than small/big on front/back. They did an enormous amout of trial and error to get 275's on the front. If you can get 275's on the front and back of the RX-8 so be it. (and for a racing app where you don't mind a lower profile tire and the wheel sticking out of the wheel well, that would probably be the way to go.)

But the RX-8 is limited to 245 in front with proper diameter tires. "So you think staggered tires/wheels are a great idea?" Well to answer your question again yes, because the RX-8 is predominantly neutral (maybe a pinch of oversteer with the stability control off?), I think small/big on the front/rear is better than small/small. BTW, getting on the trottle just a pinch more in turns and I have no problem getting the rear end to come out.

Regardless the differences are minute. On a twisty road, at most I am a little faster than stock but I am definitely not slower than my stock.

-Mr. Wigggles

FYI, Houston gets about as much rain as any city in the US. Using anything other than an all-season is foolish - IMO. For auto-X I would definitely use a different tire, but with the reduced weight load in the rear (as I described earlier) I would go with 275/30 - 18's or 275/35 - 17's all the way around and have them stick out of the wheel well a little in the front.

Comments like these is why I made my detailed post.

The looks are much better but so is the performance to some level.

Staggered is just for show, therefore rice, therefore stupid is the opinion I am trying to fight.

And my car is mad tyte. Thank you very much.

-Mr. Wigggles

You're fooling yourself if you think that you can legally get anywhere as fast as possible that tires will make a difference - even the stock 225s give you capabilities far beyond the legal limits - if you try going anywhere as fast as possible, you're going to get arrested. My goal is to enjoy the journey as much as possible, which is why I prefer a more neutral and responsive setup to a understeering, more stable setup.


But you wouldn't be any faster, as the small tires on the front would still be the limiting factor. Put bigger tires on the back, you'll still be limited to the cornering speeds permitted by the front tires when understeer sets in. It's just that at the limits of the front tires, your rear tires will have more grip, so you'll get understeer. With a same-size setup, the rears could slide at or near the same time as the fronts, so that gives the driver more options, but the limit actually would be the same.

Two points - wider tires are much worse in wet conditions, as they will aquaplane earlier than a narrower tire. With 245s on the front, your car has less capability to get anywhere fast than a 225 shod car - the 225 car would not aquaplane until at a higher speed than a 245-equipped car. That's the same reason that narrower tires should be used in winter - better grip from the narrower tires because of aquaplaning and float!

Second point - you are misinformed if you believe that all-season tires have better grip in wet conditions than performance summer tires. You can read the test results on Tire Rack yourself, where they've proved that performance summer tires have better wet performance than performance all-seasons - even and especially in standing water that could cause hydroplaning. A summer performance tire like a Toyo T1-S, Goodyear F1 GS-D3, or Bridgestone SP9000 will outperform ANY all-season tire you could come up with in wet conditions - that's a fact. It's a common misunderstanding that all-seasons are better in wet - in fact, that's not a design goal of all-season tires at all. What makes them all-season is that they change the rubber compounds to be more pliable at freezing temperatures, and change the tread pattern to provide some modicum of snow capability. No optimization for wet weather, compared to summer performance tires, is done at all. Further, it's extremely likely that a 245 summer performance tire would outperform a 275 all-season tire in dry (and especially in wet, again the width thing) conditions.

Regards,
Gordon

Charles thanks for the answer.
I did a small survey myself and found that the 225/40 and the 255/35 setup is almost the same wheel (rim+tire) diameter. The difference is 0.24% that's why I think its good.

Only problem is that the difference with the stock setup is 3.43% and 3.66% respectively. I read that no more than 3% should be exceeded:o... I dunno, guess I have to try it and see...

Another good option is 235/40/18 fr and 245/40/18 re with 1.21% difference. Opinions?

I guess I don't know - it's stock...on my Miata I had "Lanny's Alignment" done, while I was seated in the driver's seat, and loved it :D
I'll search for your numbers...

You are welcome. No other reason I can think of for going with staggered unless I somehow found a whole lot of torque.

My setup - 18x8.5 +35mm Enkei RP01 with Kumho Ecsta MX 245/40/18 using Mazdaspeed springs/struts.

http://www.murix.com/wheels.jpg

Then why did you buy and RX-8? Why do you assume that my set-up understeers?

BTW, I enjoy driving fast and I have a clean driving record.

If you take your foot off the throttle completely you are correct. I am on part throttle during a high speed turn. Something like ~25% of full throttle now instead of say ~15% on stock rubber. And yes I am faster.

Argumenative again. Have you looked at the tread pattern to Yokohama dB2? There are far more grooves for water than the stock rubber. The amount of rubber making contact with the street is probably about the same as the 225/45 RE040. I already told you why I went all-season and yes I have much better wet weather traction even with my wider tires. I light the DSC far less often (i.e. almost never) now versus stock.

You do have a point here IF we are talking about tires with the same effective wear rating. A summer tire that performs better in the wet is softer and thus doesn't last as long. The stock RE040's, T1-S, GS-D3 won't last nearly as long as the dB2's if you made the dB2's out of the same gumball compound they WOULD work better - same adhession AND more grooves.

Yes a 245 summer will likely outperform at 275 all-season IF it is a softer compound. I don't want anymore <20,000 mile tires for my car. If I got a summer (i.e. intermediate) with a harder compound, it will be worse than my 275 in the rain because it doesn't have as many grooves.

Trust me my 275's work a lot better in the rain than my stock 225's did. I been through this on the RX-8.

Not that I really care, but I am wondering what you are thinking:

A. "This guy is lying."
B. "The RE040 is a dog shit tire and thus ANYTHING is an improvement wider or not."
C. "The guy is imagining the differences" (i.e. placebo effect.)

Gord, you argue your points as if they are mathmatical certainty. But they don't match my experience and I have given you good plausible explainations (with niether A,B, or C being one of them)

-Mr. Wigggles

nice enkei's:D i'm looking at the enkei OR52 either in silver or Anthracite (18 x 8.5 with Pirelli PZero Nero M&S 2456/40/18). i got a silver 8 as well. not sure which to go for. silver woudl match..but i've seen some silver 8's with back rims they looked pretty sweet....ooooh decisions decisions:(


edit: hmm now if only i could photoshop these on a silver 8..then i cudl see if they will look good or not:p

im surprised the fact that the mazdaspeed suspension would look as low as depicted. Doesn't look .8 inch drop to me at all. Looks very nice...

Coming from an RX-7, I will say this -

I drove around with 235s all around for a while, the car was functionally useless. I put on 235 fronts on 18x8.5s and 265 rears on 18x9.5s, the car barely held the power

As far as understeer, off throttle the car had a hint of understeer, but you can easily control understeer with the throttle on a car that actually has power, transitioning slowly into oversteer.

For the RX-8, if you're stock engined, fine, stick with an even setup, however, I plan to go FI and if my experience with the 7 is anything, you can never have too much in the back. My plan is 18x8.5 on 235/40/18 fronts with 18x9.5 285/35/18 rears. I'll let you all know how it goes.

^^when are you putting this set up on your car?

Well, as soon as my 8 goes into the shop (negotiating on price for install and on the kit itself) and gets the turbo, I'll place an order for these so when the car is done I can put them on

Hopefully by the end of February if everything goes according to plan (usually doesn't, but we can dream).

...so cretinx, from what you say, a 255 rear should be okay on a modded NA rx8...

sweeeeeeet, can't wait to hear about it/ and hopfully see pictures of the install:D

I think the distinction between whether to use a staggered set up or not goes to individual driving style. I am not going to address appearances because that is wholly subjective. However, if one is the type of driver who uses the gas pedal to make it around the track then the staggered set up will be more comfortable for them. On the other hand, there are many drivers who insist that the proper way to approach a turn is to do so in a neutral(no power) fashion until the apex and then power out of the turn, in which case neutral tire sizes would suffice. Since the only cornering experience I have is from running from the cops as a young man I don't consider myself an authority unless the fact that I am still free counts.

CRH

From my own testing and research I decided to run 245/40/18 rubber alla round on my car. Alex did a staggered setup and alighenment to match, and I didnt like the feel of it since I already thought the car was a bit understeer happy (even with a good alignment). I couldnt stand it with wider rears pushing the car all over the place. With a even setup I find myself much more able to control the cars direction.

Staggered doe slook cool, but I'm making my car quick on teh track, not cool looking :D (alright, alright, I did put on clear corners, but thats a necesity!)

As I said before - on stock or mildly modified power, stock rubber or maybe 245s should be perfect all around - it will maintain the balance of the car.

When you start adding power however, there is no way in hell a non-staggered setup is going to be able to contain it. I speak from experience - 235s all around on a high horsepower RX-7 resulted in uncontrollable tail wiggling through 4th gear. I'd expect something similar on an RX-8, even though it has a longer wheelbase - the balance is very similar with the low, mid-mounted rotary engine.

I challenge anyone to find someone running a turbo RX-8 with even wheel setup that is properly balanced.

Look at these cars for example
DB9 runs 19x8.5 on 235 fronts, 19x9.5 on 275 rears.
F360 ran 19x7.5 on 215 fronts, 19x9.5 on 275 rears, the new F430 runs 225s/285s
SL65 AMG uses 19x8.5 fronts on 245s and 19x9.5 rears on 285s

All of these cars are high horsepower, the Ferrari being a sports car and the other two being Grand Tourers. Look on simliar high horsepower cars and you'll find the same types of setups - a lot depends on engine placement (mid engine tend to have even bigger rears because they tend to have insane lift-throttle oversteer) and vehicle weight.

Front drivers and all-wheel drivers never run a staggered setup because they already have terminal understeer - when you're pushing a lot of horsepower, the oversteer becomes so ridiculous on even tires that putting a staggered setup actually results in a balanced car.

To describe the feeling - the steering is a bit heavy at lower speeds, and off throttle you have to actually rely on more than the power steering to make the car move where you want, start feeding throttle halfway through the turn and it gets neutral, and give it enough and you'll still break free - apply full throttle past the apex and enjoy.

I get around the track with as much throttle as much as I can, and I insist on using same size tires as I purposely break the rear loose to combat understeer. If I had larger tires in the rear I do not believe this would be possible with the lack of torque and factory bias to understeer in this specific condition. It does not even make sense to me that larger in the rear would do anything but give more push to the front as it breaks loose first and your slip angle in the front is pointed out more than the rear pushing away from the corner.

Speculation is just speculation. On THIS car Mazda tuned the suspension using the same size all around. Unless you think you can tune the suspension better than Mazda (you might be able to if you do this all the time and have a very specific driving style and environment you are tuning for) it works best with matched all around.

Now saying that, if I go with forced induction, I would definitely reconsider, but only after I had it installed and, as all my mods have been done, felt what it really does to the car on the track. I do suspect you could make more use of larger tires in the rear with a turbo or roots/whipple compressor, but trying to compare directly to a previous gen rotary built on a shorter chassis with a different suspension setup is not enough validation to go wild with it.

Please first find someone with a turbo RX-8 who has actually been to the track and then maybe this would be a more useful challenge.

I do not doubt you would need something a bit larger in the rear though.

We'll see how well a turbo works on the course in March. If I am lucky I'll also see where a turbo'd and nitrous'd RX-8 stands in the street game, as well.

CRH

I ran staggered for several reasons, but it boils down to driving style and future plans for the car. Those plans have changed recently and I have four 275 Kumho MXs on order. The wheels are still 17x8 front and 17x9 rear, and will stay that way beacuse of the effect on slip angles.

...again, driving style. There is no "one way is better than another" when it comes to racing. What ever works for you is the best way.

It is not that simple, staggered can be a very good thing and you can tune for it many different ways... Many cars with 50/50 weight distributions have staggered setups... Mazda went with and tuned for non-staggered because it is cheaper for them per car and most owners like to rotate...

When the power of the car goes up with FI and such you will eventually need to stagger and tune for it in order to get the power to the road as going wider in front has its own set of issues...

^^i'm not too good at this...how would you tune for putting on wider tires? did you mean suspensions wise...or are you talking more power from teh engine?

Here'a a thought about tuning for staggered with the goal of higher overall cornering ability (higher g-force) than stock. Stiffer rear sway bars decrease overall tire grip on the end of the car they are put on, while reducing understeer on the opposite end of the car. So although wider, higher grip tires are mounted at the rear, you put the stiiff rear antisway bar to work to equalize front-rear grip.

End result, decreased front understeer while regaining front-rear grip balance and less overall body roll while total lateral grip capability (g-force) increases. This leverages the wider rear tires to help the front end.

I was thinking the same thing.




And for all the posts above, I simply CANNOT reiterate enough how much of a bad idea it is to run same size wheels/tires on a car with significant horsepower upgrades. I can break traction easily on the RX-8 with the DSC turned off, it's going to be ridiculous once the turbo is installed (just sent in the deposit yesterday).

Not to slight Alex's setup. I am just stating how ti feels to me. I've had much different driving experience than Alex and am definitely a much less agressive driver, with less expeirence as well. So for me the staggered setup didnt work. But then again, I dont run through 2 sets of tires in what has it ben? 20K miles?

Hell, I still have my stock brake pads at 32K!

Also, something to consider, if you run wider wheels at the back, your gonna have trouble lowering the car if thats in your plans. Gonna have to roll the fenders for that if you get a big dropping spring like I did.

ooo i see i see. tha tmakes a good amount of sense:D thanks

just wondering does anyone know how much the stock wheels weight? i was just curious b/c teh wider rims would more than likly wieght more...how would this effect your acceleration (i think that's all it woudl effect)?


edit: hehe just found out the stock wheels weigh in at ~23lbs not bad the ro_ja rims i'm looking at weigh in at around 25-26 (in a wider size) so that isn't too bad ...so i doudt that it woudl make a noticable (or even messurable) difference. am i right in concluding this....or am i way off?

you can get even lighter rims. the ce28s I'm considering weigh ~17lbs at 18x8, the 18x9 for the rear won't be much heavier...
also less unsprung weight makes it easier for the suspension on many other occasions...

Actually, 23 lbs for the stock wheels is too heavy, IMHO (I mean, those wheels are too heavy for the RX-8 already). Lots of us are running lighter winter wheels, mine are 17" at ~17 lbs. 6 lbs lighter per corner - and it makes a very noticeable difference, even dramatic difference, to the ride quality and responsiveness. The whole car rides smoother, and feels lighter and more nimble. I'd consider 23 lbs the very maximum weight I'd get for wheels, and I'd pay more (or get smaller wheels) to get the noticeable benefits of lighter wheels. I certainly would never bother putting heavier wheels than stock on the car.

Check out this new thread, Effects of wheel size/weight on performance , for lots of information on this. It's really important if you want to improve the performance and not just the looks of your car.

Regards,
Gordon

My wheels are 20lbs each without center cap in a 18x8.5. Tires are 25lbs each in a 245/40/18. You should definitely try and do better than stock.

And you potentially add more twitchy handling and lose some straight line stability. Sounds like a complex solution to a simple problem unless you really have a different driving style, more power, or just asthetics.

If someone tells me they did big in the rear for asthetics that is a perfectly valid reason. I am not sure why it must be justified in terms of handling. Reality is if you do not track your car I doubt you would really notice anyway as the limits are so high.