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Need experienced circuit racers' opinions regarding tire sizes

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Need experienced circuit racers' opinions regarding tire sizes

Old 08-19-05, 06:53 PM
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Need experienced circuit racers' opinions regarding tire sizes

Hi all!

i have a '93 FD that's pretty much all stock except for the reliability mods, and I do not plan on cranking up the boost in the next few years. i've been hitting circuit tracks for many years w/ various vehicles, but not yet an FD.

currently, the FD is rolling on some crappy goodyear 4 seasons that came w/ the car. I plan on getting Advan A048 on the stock rims and hit the circuit track with the FD this year. my question is, for circuit use (not autoX, time attack, "spirited driving") and ONLY circuit use, should i put 225's up front and 245's at the back? or should i use 225's all around like stock?

i'm looking for a balanced-feeling car. i was thinking that there must be a reason why mazda chose 225's all around, and that i probably should not ruin its balance by running 245's at the back. but i could be wrong, perhaps the FD came with rear tires that are undersized.

welcome all experience opinions

thanks a bunch!

howi
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Old 08-19-05, 11:19 PM
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If you don't have a lot of track experience, you might want to stick with street tires for a while, for two reasons. One is they're cheap. Two is, if you're new, street tires will show you your mistakes much better than track tires will.
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Old 08-20-05, 08:04 AM
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Just run 245/45/16s all the way around. Have you noticed rubbing before?
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Old 08-21-05, 12:28 AM
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Originally Posted by Gene
If you don't have a lot of track experience, you might want to stick with street tires for a while, for two reasons. One is they're cheap. Two is, if you're new, street tires will show you your mistakes much better than track tires will.
I disagree with that statement. Although it it true that street tires can not achieve cornering speeds of a R compound tire, that does not mean it's easier or safer than using R compounds.

Going slower is safer yes, but being in control is the ultimate goal. Going slow and not being in control is just as bad or if not worse than going fast and being in control.

Generally street tires have poor recovery when you exceed their slip angles. R compounds have generous slip angles AND they recover well. Meaning if you cook a corner, the Rs will be much more forgiving in keeping you from going off the track. Either recovering from excessive understeer or excessive oversteer Rs will always be better and that is why Rs are the way to go regardless of skill level.

Going off on a corner can potentially roll the car, not mater what type of run off.

To answer the tire size, just run 245 all the way around ont he stock wheels.
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Old 08-21-05, 10:01 AM
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I never said that street tires are easier to drive. Of course they're not. That's my point. Because they're crappy and don't recover well, they show you your mistakes much more clearly than an R compound tire can. When you're looking to learn, this is a good thing. At the beginning of your track school career, going fast is not the objective. I've been doing them for a a few years now, in a well-prepped Turbo II with sticky R compounds. Last track event it was in the shop, but I had already registered, so I went with a rented Pontiac Grand Am, with stock crappy everything. It had shitty all-weather tires, bouncy, floaty, soft suspension, and I learned a lot driving it and keeping it together.
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Old 08-21-05, 11:04 AM
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gene, please. if you're not gonna help answer my question, please don't post in my thread. your subject of discussion is totally irrelevant to my question.

regarding running 245's all around, i woudn't want to pay the extra money for tire sizes that i might not need at my power level (all stock). otherwise they'll just be dead rotating weights.

anyone out there w/ experience for different tire choices on a stock FD? I'd grealy appreciate some feedback on how a stock FD behaves with stock tire width, staggered width, and overall larger width.

thanks again,

howi
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Old 08-21-05, 02:27 PM
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I also disagree with using street tires on the track. They are NOT cheaper than R compound tires! I have seen street tires destroyed during an open track event, in less than one day. They cannot handle the heat, and so they chunk and basically the tread comes apart.

I have seen SOME street tires last OK on road course, but it's hard to say if that was due to the tire compound/construction or simply conservative driving.

R compound tires, as before, are much more predictable. Sure many street tires are less forgiving in breakaway, but for a newbie this is BAD. Plus the track operators tend to send you home if you start rearranging the tire walls with your car.
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Old 08-21-05, 06:13 PM
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to chime in, the general consenus is that we are better off running r comps at the track? I have a set of BFG KDW's
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Old 08-21-05, 08:53 PM
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Originally Posted by Howi
gene, please. if you're not gonna help answer my question, please don't post in my thread. your subject of discussion is totally irrelevant to my question.

regarding running 245's all around, i woudn't want to pay the extra money for tire sizes that i might not need at my power level (all stock). otherwise they'll just be dead rotating weights.

anyone out there w/ experience for different tire choices on a stock FD? I'd grealy appreciate some feedback on how a stock FD behaves with stock tire width, staggered width, and overall larger width.

thanks again,

howi
Hey, I was just trying to help based on my own experiences. At stock power levels you probably don't need bigger rears, especially if you are going with stickies.
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Old 08-22-05, 09:14 AM
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Originally Posted by Howi
Hi all!

i have a '93 FD that's pretty much all stock except for the reliability mods, and I do not plan on cranking up the boost in the next few years. i've been hitting circuit tracks for many years w/ various vehicles, but not yet an FD.

currently, the FD is rolling on some crappy goodyear 4 seasons that came w/ the car. I plan on getting Advan A048 on the stock rims and hit the circuit track with the FD this year. my question is, for circuit use (not autoX, time attack, "spirited driving") and ONLY circuit use, should i put 225's up front and 245's at the back? or should i use 225's all around like stock?

i'm looking for a balanced-feeling car. i was thinking that there must be a reason why mazda chose 225's all around, and that i probably should not ruin its balance by running 245's at the back. but i could be wrong, perhaps the FD came with rear tires that are undersized.

welcome all experience opinions

thanks a bunch!

howi
on stock wheels 245s all around are the hot ticket. even stock power levels can overcome 225s pretty easily. especially once the tires get hot on track. a larger contact patch will give you better breaking as well as better traction and overall grip. 245/45/16 fit the stock 8" rim very well and should not cause any kind of rubbing issues up front unless you are running too low.

fwiw, i've heard a lot of people posting in the suspension section about rubbing when using Tokico shocks.

hope that helps.
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Old 08-23-05, 01:04 AM
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I've run my fd on the track on crappy uniroyal tigerpaws (minivan tires in 225/45/16), advan 032Rs (245/45/16), and hoosier rs04's (245/45/16). When I first had it out on the tigerpaws I loved the balance of the car, but it obviously needed more grip. So I upsized to 245's and got the advans. That was great until I cooked my hawk hps brake pads and put on n-tech competition pads. Suddenly the advans didn't have enough grip under braking, so I switched to hoosiers. I've found the car easy to recover on all 3 tires, btw, although the tigerpaws were fun because they felt more active even if I was going slower.

In any case, all the advice I've gotten from the board says to run the same size all around for circuit use and I've found the balance exceptional with 245's so I'd vote against the staggered size. If you haven't run the fd on the track, logic says run it with what you have and learn how it behaves, then decide what you need to make it behave better.

BTW - I have Eibach Pro Kit springs which I think lower the car a little over an inch and never have rubbing problems.
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Old 08-23-05, 01:07 AM
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Of course, now that I think about it, common wisdom around here says to run about 2psi lower in the rear (I would guess to reduce oversteer). Wouldn't upsizing just the rear tires have the same effect?
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Old 08-23-05, 07:43 AM
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i just finished a weekend on 245-45-16 A032R's. car felt supremely balanced, even with the stock springs and shox. see my vid in this section if you want. it was my first time open tracking with the FD.
if someone is completely new to open tracking, good performance (non R) tires are usually recommended. you will learn a lot on them. R's usually hide driving errors. so i also think its best to start on normal street tires; they will communicate audibly to you, and have more gradual breakaway usually versus R's. after 2-3 events, step up to the R's. just MHO.
regardless what you do, you will have a blast.
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Old 08-23-05, 12:12 PM
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If you've decided on the A048's then the question of using 225's or 245's is a non-issue. I don't believe the A048 is available in the correct 245/45/16 size.

I would stay with a balanced setup, that is the same size tire front and rear.

Most people go to the 245/45/16 fitment because it is the widest tire and therefore largest contact patch for the stock rim. Yes, the 245 is a bit heavier by a pound or two, but is more than made up for by higher lateral grip limits.

Originally Posted by Howi
Hi all!

i have a '93 FD that's pretty much all stock except for the reliability mods, and I do not plan on cranking up the boost in the next few years. i've been hitting circuit tracks for many years w/ various vehicles, but not yet an FD.

currently, the FD is rolling on some crappy goodyear 4 seasons that came w/ the car. I plan on getting Advan A048 on the stock rims and hit the circuit track with the FD this year. my question is, for circuit use (not autoX, time attack, "spirited driving") and ONLY circuit use, should i put 225's up front and 245's at the back? or should i use 225's all around like stock?

i'm looking for a balanced-feeling car. i was thinking that there must be a reason why mazda chose 225's all around, and that i probably should not ruin its balance by running 245's at the back. but i could be wrong, perhaps the FD came with rear tires that are undersized.

welcome all experience opinions

thanks a bunch!

howi
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Old 08-23-05, 02:37 PM
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If you go Rcompound, use the TOYO RA1 period. they will treat you well, and get better with wear. they do not require heat cycling(per TOYO), wear longer than the A048/A032, or any other compound, and are faster than all but a couple of the R compounds. I run them on the street on my daily driver 450rwhp Supra, and they are great. For the street, you cannot beat the Kumho MX, although the RT615 is a little better, it will probably last half as long. A RA1 in a 245-45-16 will be a little shorter than stock, and run about 170.00 each. carl
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Old 08-23-05, 02:39 PM
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I'd be interested to see a comparison, I run the A032r's on the street and at the track and have been very impressed with both their performance and durability. They look practically like new after a day at the track and 2-3 thousand miles.
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Old 08-24-05, 12:08 AM
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thanks for all the reply guys! u've all been the most helpful!
for now, i'm gonna run the goodyear 4 seasons on the track till their done, just to see how the car behaves.... its behaviour will be much more exaggerated compared to r compounds.

thanks again!

howi
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Old 08-24-05, 12:25 AM
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Enjoy! And be sure to post your experience, I'm sure others will find this thread and have the same questions.
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Old 08-31-05, 10:55 PM
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It sounds like you have enough experience to handle yourself on the Yoko's, but I read some things that should be addressed for the record's sake.

I've run 225 AO32's and a 245 "max performance" street tire. Track instructors and Tire Rack will tell you, street tires are more forgiving because they have more gradual break away than R compound. This does make it easier to learn car control than on R compound where the lne between grip and no grip is more sudden. I went from the AO32's to the street tire with less grip so I could learn more and have more fun catching the car as its tail swings out with the greater confidence inspired by the street tires.
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Old 09-01-05, 09:22 AM
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I agree, I started on street tires, switched to R-compounds for a few sets (of tires), and then switched back to street tires. Next set will definately be street tires, they are too much fun.

I have also found significantly longer tire life in the street tires. The current Yoko ES100s I'm running will probably see about 14 event-days before I replace them (they are at 12 now). The Victoracers once I really got running on them lasted 3 event-days, tops, before they corded. It's nice to not have to back off on the driving in order to make the tires last (like I had to with the Victos), with the ES100s I can go out and drive 100% all day. I may have to slow down due to other reasons (such as overdriving them), but I don't have any worries about cording.

I would definately recommend switching back to street tires occassionally, even if you're a hard core R-compound-er. My driving has improved significantly since I switched back to a lower traction compound.
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Old 09-01-05, 12:15 PM
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There seems to be some disagreement in this thread about which tires break away more safely. I've always heard (and experienced) that it isn't that R-compound tires have a more sudden loss of traction, its that they don't announce in advance that they are about to lose traction. Therefore, when it happens, it feels more sudden. I've found that with a032r's and hoosiers I still need to catch the tail occasionally, you just have to listen for it differently.
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Old 09-01-05, 12:17 PM
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Originally Posted by jayk
you just have to listen for it differently.
If you're "listening" to catch any car on any tires you're already too late.
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Old 09-01-05, 12:24 PM
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My old uniroyal tigerpaws did alot of squealing way before they actually started sliding. But I actually didn't mean literally listening with your ears, especially with r-compounds you have to listen with your hands and seat of the pants just as much.
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Old 09-01-05, 12:33 PM
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At the limit street tires are tremendously more forgiving than race tires because street tires can maintain much higher slip angles without completely breaking loose. The only thing you have to watch when racing on street tires is that you don't overheat them as the rubber will then chunk. That is why when forced by rule to run a street legal tire all the competitors will shave most of the tread off: it makes the tire run cooler. So if the tread on your street tires is about half worn already you'll have far fewer problems with heat at the track. Keeping the tire pressures high enough will also help keep street tires from overheating.

I've driven on many tires and I've helped and instructed many drivers on many tires. No ifs ands or buts about it, beginners learn more by starting on street tires. They are much easier for the beginner to understand because their level of feedback is slow and honest and allows them to really feel what the tire is trying to say through the car. Sure they'd go faster around the corners if on race tires but they'd be terribly under driving the car because they don't understand how the tire communicates with them in different situations.

Make the driver fast first, then make the car fast. If you make the car fast first the driver doesn't know wtf to do with it anyway.

...and anything is forgiving if you're just putzing around
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Old 09-01-05, 12:58 PM
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Not to hijack a thread or throw out some ludacris idea but I've heard of some people running bigger tires in the front, especially with lower power levels. I guess the reasoning behind it is bigger tires in front allow the car to respond better to the direction you point it in, most of the brake load is held in the front and so on...

Not to sound completely uneducated but this may not pertain to you and circut racing, but maybe autocross?
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