pcs

iTrader: (2)

I'm looking for a set of wheels/tires for track days, but I'm wondering if 255/40/18s would be more grip than I need with a stock powered 8, to the point where the additional grip would be slowing me down. I'd be looking to go with 255's all the way around...

the other option is to go w/ 17s and go 245/45/17's though the OD would be slightly smaller than stock...

just don't want to be tracking on my 19s - those rubbers would add up QUICK!!

thanks in advance -

Anijo

IMO, go with 255/40/17's. There are a lot of tire options in it and they're universally cheaper than you're going to pay for any of the 18's. You're dropping the outer diameter to 636mm (from 659 stock) which works out to your speedo reading 2.5mph slow @ 60mph. You can pick up a set of 17x9" RPF1's for ~$250/wheel off of tire rack (I bet Rishie at AutoR&D can beat that, btw) and then Star Specs are $155/tire in that size.

BTW, this is a fun tool: http://wheelsmaster.com/rt_specs.jsp

dozer

iTrader: (3)

^great advice

shaunv74

+1 that's the exact size I'm running. It's definitely the best way to go.

costello

Never heard of more grip slowing anybody down. I run 275/35-18 Toyo Proxes RA-1 for track days. Just go with what's in your budget. Smaller wheels & tires do cost less sometimes.

tiltmode43

iTrader: (15)

He's referring to the greater rolling resistance + weight being more of a burden to power than a blessing to grip. More grip isn't always necessarily better.

pcs

iTrader: (2)

that is a very cool tool to play around with... Thanks!

It looks like a 255/45/17 would fit closer to my stock diameter, going from 663-662 (I am on the 19" R3 rims)... is that even a size that is readily available?

which size? what Anijo mentioned?

yeah, I was just thinking that I don't want to deal with any clearance issues, and didn't want to carry the extra weight or cost if i didn't really need the additional width, esp. in the front... but then I also don't want to run a staggered setup...

Anijo

Honestly though, if he's doing track days and not competitive racing I can't imagine that being very noticeable. Don't most Track Days make you run with your windows down anyway? One of the more experienced 8 owners in my area when it comes to track days is still so slow around Pacific Raceway that he'd be lapped during a Spec Miata race there.

The OP has a LOT of experience to catch up on before something like extra friction adding too much "drag" will impact the sheer enjoyment/terror of Track/Lapping Days

Anijo

Hmm, I actually didn't know you were referring to the R3 wheels, is their outter diameter any different from us on 18" Stock wheels? Go by that, not by what I said. Also, as for going 255/45 instead, they don't make Star Specs in that size I bet you could get an equally competitive tire in that size, but locally we do a few AutoX's in the rain and the Star Specs are regarded to have the best wet performance

Any idea how much those weigh? You'll be SHOCKED how much you'll feel the difference of losing 4+lbs per wheel when accelerating and turning (the wheels will be 7+ lbs lighter but the tires will weigh a bit more). They say every lb of unstprung weight you remove from the car (e.g. brakes, wheel, tire) is like removing 14lbs from the chassis, so losing 4lbs/wheel is like losting 224lbs off the chassis.

Just hit up the "Will it Fit?" thread in the wheels/tires section with the specific wheels you want + tire size/brand and someone should be able to help. I was concerned about rubbing (my car is dropped on coilovers) + having a lower car is "better" on the track anyway right? (SEE THE QUOTES AROUND BETTER?! No one Nitpick me )

pcs

iTrader: (2)

i don't doubt that... I have MAYBE a dozen track days and less than a dozen auto-x days under my belt... but wouldn't mind getting better. I am more concerned with the pricing and driveability off the track with that much rubber in the front... which is why i'm wondering if it's overkill... besides... that's extra unsprung weight

no idea about how much the r3 wheels weigh... did a couple of searches and came up empty, though i may not be looking in the right places, or in the right ways... it's tough b/c i think the search function requires 3 letters in order for it to be a part of the search query, but 'R3' is obviously less than 3 letters, lol. I think they are forged wheels though, so they shouldn't be THAT much heavier... I read 1lb unsprung = 4lb chassis... could be wrong though.

the OD i used was based on the stock tire for the r3 - 225/40/19, which put it at i think 26.1". I'm in socal, so i don't really worry about the rain too much. Was looking at Hankook RS3's or the Falken Azenis 615's.

I don't think i'll have too much problem with fitment since i'm on stock suspension... I want to get in a few lapping days / auto-x before I start modding the car... it'll give me a better appreciation for the car, and besides... i'd like to see how Mazda set up the car. Only reason i'm not going out on the stock wheels/tires is it's so pricey =P

tmak26b

hated my 265 35 18 on track

EricMeyer

Your suspension will be a bigger limitation than your tire. When thinking of a tire and wheel combo you must think of the suspension as A SYSTEM. Just like you have noted that you are running a stock engine (which means you want be running 180mph at the end of the straight, hit the brakes and need huge grip to slow the car down), the same thing can be said for needing grip when accelerating---you don't need huge grip when you step on the gas. I GUARANTEE you won't have enough power in a stock car to need that much grip for acceleration or braking. You MAY have braking issues when using the stock suspension. More front tire grip running the stocker soft springs will make the front stick like glue and pull the rear's out of the equation. You'll see this in the individual wheel speed data sports fans. This is the "light" feeling some of you may have experienced when your tire grip levels are high and you're running stock springs and a good brake pad.

Now let's talk lateral grip. If you run a stock suspenion your car will still roll over like a beached whale with any tire you choose. This means you can buy whatever tire size you wish and your inside grip level will still suck. Does that make sense?

Here's what I would do if I were you. My guess is that you are new to the track driving thing or you wouldn't be asking this TYPE of question. If you really want to propel your driving learning curve, you DO NOT want huge grip. You don't even want large grip. Medium grip at best. I've instructed and coached way too many a driver who has added every possible F__ked up mod to their car and this always stunts their learning curve. I'm contributing to this thread both for your question and to help steer new and intermediate drivers down the path of faster learning (and therefore driving), safer experiences, less expense and less headaches.

The real question you may want to consider is this: What is your goal?

If you want new wheels and more grip because you just want new wheels and more grip, then I would get a set of 17 X 9. There is plenty of cost effective tire options to take advantage of (and they are usually IN SUPPLY). They fit nicely under the wheel well (which I'm guessing you may lower for looks and not for performance) in the future??

If you think you'll upgrade your brakes (TOTALLY not necessary with a stock engine and slightly modified suspension) you'll want to insure that your new fancy colored calipers will fit inside the new wheels and tires you'll be shelling out a few bucks for.

Again---you don't need a lot of grip and wheel. A 245 tire on a 9" wheel is plenty. Your real investment should be in SUSPENSION. Suspension will make your current or stock tire contact patch waaay better. Even more important than this is you can use a different tire on your same stock wheels and this will give you important feedback on how your driving style is influencing the car's attitude on the track.

One of the things people don't get is the influence a tire has on setting up your car's suspension. IF you put a gigantic tire on a car and then build the suspension around it you're in for some big challenges. I see this all the time. The other day this poor sap with a new C6 Z06 with a freakin' power adder and a monster set of Hoosier R6's (he was a beginner driver) corded both left sides of this new $400 ea. Hoosiers. HPDE 1 and he is cording R compound tires that he shouldn't be running anyway. This poor guy has NO flippin' idea what his car is trying to tell him because his car has waaaay too much capability for his driving skill set. He thinks he's a fast driver (in reality it's the car) and his car and grip are so insane that he has no idea what the car is trying to do. He is missing the opportunity to drive the crap out of the car and have the brakes fade, the front left tire rolling over, the car over or understeering. Everything. This is how you learn fellow gangsters. This is a similar issue for you and a 255 tire especially if you're putting a shaved R compound on there.

One last thing for all of you----just because a tire manufacturer publishes a tire that says "255" or "245" it doesn't mean jack crap. Look at the actual contact patch of the tire. Look at the tire specs. I have seen 225 and 245 race tires from different companies (both 17") have the exact same contact patch width. Get the picture? Do your homework gang. Remember, lots of people post things on these forums because they read it or their brother in law's best friend use to work at a dealership and......

Happy rotoring and feel free (and of you) to contact me with any questions. Winter time is the time when you work on your car for next Spring. Winter is the time when suppliers have parts in stock (and then they run out when all the last minute knuckleheads buy stuff 1 week before their first track event next Spring). Vendors love working with people in Dec to February because they have time to invest in you. They have time to talk. In april all heck breaks loose. Everyone needs everything overnighted. HPDE drivers ask fabricators to put roll cages in two weeks before their first NASA event when these same fabricators sat idle in January. These vendors will quote you a month or more BECAUSE YOU WAITED TOO LONG TO GIVE THEM YOUR MONEY.

Start thinking ahead today about next year's track game plan (like our friend here with his 255 tire overkill question).

One last thing (I promise). The best thing for these cars is a big set of sway bars. Bars allow you to run softer springs and therefore something you can drive on the street that doesn't kill you or your passengers. Swaybars help reduce the cars ROLL. These cars have a fair amount of roll and they have MORE ROLL when you add more grip. Bars are cheap, you can install them yourself and they help your stock (or other) tires work better and last longer. The best money you can spend is in a set of bars. Make sure they are adjustable. Make sure the end-links have HUGE adjustability. End links are the easiest things to make in the whole world and tons of people sell them for twice what they pay for them and they suck because of lack of adjustability length.

OK. Off the soapbox. Apologies.

Happy rotoring.

Meyer out

Kafka

Hi Eric, thanks for your excellent posts based on real racing experience. I always enjoy your posts and its NOT lengthy at all :P

I have a 2007 Rx8 GT which is my only car for DD and about 5 track days in the summer with winter tires for the winter. (Driver use profile)

I do not want to lower my car a lot since I need the ground clearance in winter. I have minor power mods (exhaust, k&N filter, accessport tune by MM).

I would love to have less bodyroll, more grip while maintaining the good ride quality. (Driver goal)

I use my stock rims with 245/40/18 BFG R1 for track days. And I use a lighter Enkei GTC01 rim 8" for stock Potenza tires 225/45/18. I may change it to a 245/40/18 for daily drive but the fuel economy probably gonna be even worse.

That said, what kind of sway bars you recommend to improve the drive while maintaining the great BMW like ride-compliance?

Will Racing Beat Sway + Springs a good combo? What if I also add Bilstein shocks? Will it make the ride too harsh? What would be your recommendation/approaches?

Thanks and have a great day!

pcs

iTrader: (2)

my goal is to go have fun on the track and learn my car... not my first time on the track, but my first time w/ the car. a small amount of prior experience in an n/a fc and a speed6. The reason behind wanting to get new rims/tires is not that I want to upgrade anything to fatty rubbers, it's more that I don't want to be doing track days on my 19" stockers. That would be too pricey for me. But while I'm getting new wheels/tires, I figure I might as well look into perhaps more rubber than the stock 225's.

I've been looking, and I think I may actually just end up with a set of 18" stock rx8 wheels with maybe 245's high perf summer tires of some sort at the most. I'd rather learn my car's limitations before I upgrade suspension and brakes (do not anticipate going bbk, at most fluid, lines and pads). I feel like I'd appreciate the mods more, and I'd actually know what the difference is as opposed to speculating the difference.

My money will be better spent on the nut behind the wheel, not a bunch of performance mods at this point, and I know that...

thanks for the tips, Eric - I'll most likely be hitting you up with more q's at some point.

-pcs

tiltmode43

iTrader: (15)

Posters like meyer are partially the reason why I've been migrating back to the performance aspects of our car, great stuff!

EricMeyer

Not familiar with a lot of the steet/track suspension however I've heard the R.B. setup is nice for street/track. Soft spring rates and firmer bars. Honestly I'm hindered by driving a much stiffer car. You should ask someone who is actually qualified to answer this. Reccomend someone running NASA TT class. Your plan sounds smart.

EricMeyer

GREAT GOAL!!!!!!!

Remember this: Using the same size tire all the way around allows you to both ROTATE a tire and also FLOP a tire. When street/track cars with only a little amount of camber use tires over a season the lack of camber wears much more of the inside of the tire. Using a non-directional tire is the way to go. This way you get to "flop" the tire on the rim halfway through its life cycle and extend the wear. Cars that are setup properly will wear the front left more than the others with little wear on the right rear. Rotating your tires after each weekend (or even each day) really stretches your dollar and maximizes your performance. Another thing you might want to consider (and some people think this is gay) is to get the little trailer and haul these "track only" tires, your toolbox, cooler, jack, pop-up tent, chairs, etc. You see the Auto-X guys do this all the time. It makes for a better experience all the way around.

Tire word of advice. If you get an R compound, start with a rain tire. It will have more tread, you'll get more life and the grip is a nice little step above a performance street tire. However the grip is not too much. An added bonus--the tire works in the rain too! (something a "shaved" R compound can NOT do). The Toyo RA1 is a great choice to make as it lasts long, is predictable and you'll get an honest season out of it when you have the little trailer.

Nut behind the wheel: Smart drivers are thinking about 2010 right now. May I suggest to everyone that the better learning curves come when you drive new tracks. Driving the same track over and over again for 5 years is not 5 years of driving experience----its 1 year experience 5 times! Learning a new track taxes your mind and therefore your skill set. Going to new tracks catapults your learning curve. You'll want to study before you go there to make the best use of your visit. Racing and HPDE Videos, track maps, talking to those familiar with the track (talk to someone MUCH better than you to learn) and the efforts that drivers who really want to learn must exercise. Learning to drive can still be fun when you prepare, prepare, prepare. In fact I'll offer that it's more safe and more fun. PLUS, its great to pass your buddies the first time you run on their home track. They're like "WTF? HOW THE F__ DID JOE JUST CRUSH ME THE FIRST TIME ON MY HOME TRACK?" Pro drivers enjoy helping those who want to learn. Set you TIVO for Grand-Am and SPEED W.C. events to learn the line, find visual cues and watch where they start their steering inputs.

Most of the NASA schedules and about all of the Pro Sedan racing schedules are already out. Go to NASA and run HDPE as you'll also get the benefit of watching the racing lines and have access to faster drivers who are willing to help.

As always, if anyone sees our team at a track---come on over and find me. We usually travel with at least one other really fast race car driver familiar with our cars that is willing to offer .03 This year we are running a full compliment of ChaseCams in all our cars and will be posting "good laps" for drivers to reference. This will include both in-car looking forward, in-car looking at driver and above car to see the line. One good thing about these crazy rotary motors with headers is they are loud. Hearing the application of throttle in a video is VERY helpful to beginning drivers and most apply throttle way too early (I did it too) and induce understeer mid-corner. The secret (shhhhh.... don't tell anyone) is to slow down less, roll through the corner faster and go flat as early as you can without understeer. This is way more difficult than it sounds. Everyone can EASILY find an honest second per lap when they practice, practice, practice this technique. EASILY. The time is in the corners guys---not the straights. Exit speeds out of the corners (a function of mid-corner roll speed) is the ticket. These cars are plenty fast in the corners when you have a functional tire contact patch. Hint hint----invest in suspension.

Gotta go. Time to make the donuts.

Please remember that I will help via phone or email anyone that really wants to learn. All I ask is that you pass it forward to those also wanting to learn. Caveat: If you are ultra-conservative, have a hard time pulling the trigger or subscribe to consumer reports, don't contact me please. I want those who are chompin' at the bit to learn. It's easier to slow down a race horse than to make a Derby winner out of a mule.

Happy rotoring.

alnielsen

iTrader: (4)

The OP doesn't say he is running in any series or timed event. He just says he is tracking the car. He also states that learning is his priority. In this case, tire grip shouldn't matter as much as having a safe tire would be. With a expensive grippy tire, you wouldn't learn car control as easily. You'll be able to feel the limits with a less aggressive tire.
My first track day, with this car, was on the OEM tires. DSC quickly became more of a problem than the tires. I later moved to 245/40x18 Falken's.

altiain

iTrader: (3)

I’ve been tracking a stock-powered RX-8 for two years with exactly this combination – 17x9 wheels and 255/40-17 tires (RA-1s and R888s in my case). Like Anijo said, 17” wheels and tires are almost universally cheaper than 18” options, and 255s work well on the car. Just make sure to buy wheels with a positive offset of +35mm or higher (I use +35mm wheels without issue, although most people run higher offsets).



Also, contact Alamo Autosports if you’re looking for RPF1s. I just picked up a set of 17x9 +35mm RPF1s from them a couple of weeks ago for a lot less than $250 a wheel.

altiain

iTrader: (3)

I think the RB springs are a pretty good compromise between improved performance and ride comfort. I drove my car for the better part of two years with Koni shocks and RB springs and found it to be quite comfortable for street use, yet significantly more capable on the track.

Two things I'll suggest:

• Definitely take Eric's advice on sway bars. The pic above is with RB springs, Koni shocks (set relatively stiff), and stock swaybars. Notice that the inside tires aren't doing very much at all. I later added a set of Progress swaybars in combination with the RB springs and found the combination worked pretty good on the track for a daily driven car.
• Do not upgrade the springs without upgrading the shocks. The stock RX-8 shocks are relatively underdamped even with the stock spring rates. They will not last long at all with stiffer springs. If you're going to take the time to replace the springs with something a bit more aggressive, add a set of adjustable performance shocks (Konis and Tokicos are the popular choices) as well.

pcs

iTrader: (2)

Eric - good points, and I've done that in previous cars... it's just been a while since i've been out... I don't go as consistently as I'd like, but on the west coast, I've run on CA Speedway's Roval, Buttonwillow in multiple configurations, Streets of Willow, Willow Springs, and Laguna Seca... On top of being out on the track, I'm always asking for rides, and for the instructors or faster drivers (who aren't douches) to ride along and give me tips on what to look for, how to read a line the first time out, etc...

For a while, I would go out with a couple guys, and each time, at least one of us would trailer our cars (sometimes two of us, depending on the track), with extra tires, a bunch of extra parts (belts, hoses, clamps, etc), tent, chairs, cooler, etc. good times

Looks like I have to get a Go-Pro mount for my car somewhere...

TeamRX8 - I am not concerned with getting the grippiest tire, I am concerned with the cost associated with tracking on my 19" stockers. However, if I get an alternate set of rims, I figure I might as well go wider than the 225 stock widths. Priority at this point is the driver mod...

thanks for the tips, guys - keep them coming if you have 'em!

pcs

iTrader: (2)

any idea if the R3 springs are the same rate as the sport or GT springs? I'll take that under consideration - my FC had RB springs, adjustable sways, and adjustable KYB's....

How are the R3 bilstiens with upgraded springs?

again, at this point, I'd rather begin to reach the limit of what I can do with my stock setup before moving forward with upgrades... This includes having an instructor or two drive my car at the track w/ the stock setup to see what exactly I could do with the stock setup before I start modding the car...

burglar

My $.02 (worth less with the exchange rate)

If it's your first time on the track with the car, just drive it as is. Fresh oil, coolant, and some track-specific brake pads with a fresh bleed.

The car will be a blast to drive, you'll learn a ton, and you'll spend minimal money.

When your skills improve, you'll realize what on the car you have to change. Here's the payoff: when you do put on those fancy swaybars, big brakes, or sticky tires, you'll feel where your money went by what it changed on the car. You'll appreciate your mod and the work to install it that much more. You'll be faster and happier. And isn't what it's really all about?

alan23

Thanks Eric

Always can look forward to you giving some good advice.
Especially to amateur enthusiast like me...

I am running 225/45 tires second time for my rx-8 and changed my suspension, sways but have not adjusted much yet (want to concentrate on my driving and improve my consistency before factoring suspension adjustments)..........
Probably my target for 2010 is to attend more trackdays and learn to adjust my suspension/sways

Cheers
Alan

Kafka

Thanks for all the responses and advises!

I will have to save up more over the winter for a RB Sprig + Progress / RB Sway + Bilstein/Koni shocks combo and then just keep going to HPDE as much as I can...then FT86 in 2012 lol :P