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YOUR RESEARCHFavorite C2 Wheel/Tire Size Combo for track
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toe issue
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I forgot to mention, it turned out to be a toe issue.
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I checked the area you mentioned was rubbing on your rear wheels.
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Here is my case: I am running 225/45 and 255/40 on 17" wheels on Direzza street tires at the track and street.
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What negative aspects will I run into once I mount the taller 305?
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Anyway, long winded answer to say while I am still a novice skill level driver with a great amount to learn, those who have seen me drive recommended I move on.
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18x9/18x12 with NT01 245/40 18 and 315/30 18. I'm going to try a 18x10 up front soon but takes a little bit to get that working.
Edit: figure out what tire you want to run, check available sizes, than get wheels best suited for that size. Street, slicks, etc...
Not to be a Debbie Downer......but from reading the thread in the DE section I think you need to adapt to your car 1st while keeping it stock before going to track tires. Look at trying to get the most out of the car as you can as stock. Then I would look at improvements like alignment, suspension, oil delivery and tires. If you do all the changes all at once you will have no understanding of how each component changed the drive. Baby steps. Good luck!
I appreciate the feedback. I really do. In car control on Saturday I was able to induce understeer with wheel and throttle, oversteer with throttle and drift with brake and throttle. The balance on the car is nice right now. When I hit the corners right I get a nice bit of oversteer and when my entry was poor I would get oversteer.
I then got to go on the same course again the next day for Autocross and took the Hoosiers. They are 245 on the front and 275 on the back. About half the group had r-comp tires. The Hoosiers were a completely different experience as there was no understeer with the 245s. Because they are worn out though, they were slicker than snot on the first two laps. As they warmed up, the rear was still quick to slide but easier to control. Out of a group of 33 I finished 12th.
I've talked to several of the top guys/instructors around here that have seen me drive and they all said to move to r-comp and start learning how to control them better. With my suspension upgrades starting to show up, I would like to decide what tires I am going to run and then start getting everything adjusted out. (Our top local Porsche racing mechanic will be doing my alignment and verifying my installation and setup.)
tl;dr. Anyway, long winded answer to say while I am still a novice skill level driver with a great amount to learn, those who have seen me drive recommended I move on.
I have +68 with only -2 deg of camber and they fit no problem. No roll in the rear. I was using 245/275 NT01s but the rears were just getting worked. If your using Hoosiers (I drive my car to the track so slicks have always been off the table for me) the 275 rear may work really well.
Ok, cool. I was surprised by how much of a difference the 245's in the front but they made the 275's seem really small. I'm shooting for R888 or NT01 depending on the size for exactly the same reason. Thanks for the input!
I run NT-01s - 235/40/18 in front (may go to 245) and 315/30/18 rear. With some camber it's a really good set-up. Won POC class championship last year with that set-up and set POC track records at Willow Springs and Auto Club Speedway (and drive to the track). It works!
Why's that funny? Lol, jk, that's awesome! For the record, I don't want to be in the fast group. I wouldn't be able to ride along and see their lines if I was.
Dunno, I see a lot of peeps always trying to fit the widest tires they can which often doesn't translate into a faster lap time for most of these guys. My $.02
Personally I don't think our cars have the justified HP levels to really make use of the wider tires(past 305). Also good luck clearing the fenders/liners/suspension depending on your setup.
18x8.5 et40
18x11 et63
Those are IMO ideal for 996 NB without any kind of fender rolling/modifications and such.
What problem are you trying to solve?
Here is my case: I am running 225/45 and 255/40 on 17" wheels on Direzza street tires at the track and street. Under tired? Yup! and perfect as I explore the limits of this RWD car that handles like a FWD car with better throttle steering. I have been track driving (FWD and RWD) since 1998 and it took me about 3-4 track events to even figure out this car and get it sliding around. I will wear these tires out and get to the point of passing the adhesion limits (just about there) and then eventually move up to street tires on 18" wheels (I will never go to R-compound, unless racing...been there and done that. R compound is not needed for HPDE).
Watch this. You'll notice the rears get very sensitive after a couple hard laps.
9-19-15 BW CW13 996 - YouTube
That's on 275s. The 996 can definitely make use of 315s. I would love to try 305s but the gearing is already long on our cars for most tracks (at least where I live) and 305s are like an inch taller. I do agree (very much dependant on offset, camber and means of gaining camber) fitting larger *front* tires may require some work. But 315s clear pretty darn easy in the rear.
I like NT01s because they stay pretty consistent for a ~20min session, they have good sizes, they work great until corded and they're cheap. Other "street" tires don't handle heat as well usually letting go after 1 hard lap. But a couple do offer 285s and 295s that are the right rolling diameter. I bet if you went NT01 you'd never go back.
JJ1,
I do get it about the advantages of R compound (I raced cars for a year and had R compound on other cars that I tracked). So, I definitely understand what you are saying.
Advantages of street tires=> rewards smooth driving, doesn't hide mistakes, learn the limits of the car (slides more). When they over heat, which they tend to do, I just put in a 5/10th's lap and practice my line, temps come down a bit and then I get back on it. By then the 20 minute session is over anyway.
Caymans and Miatas. Duh. Seriously, why wouldn't I ask the guys that have spent the time to figure out what the best setup is and then build towards that? Why not get it handling at 80-85% of its limit then go learn it inside and out? If this is my 7th car over 300hp and it's been my dream to do this why wouldn't I? If I do drive like "flat out", then call me on it at the track.
Compared to my 997tt and my M3, this suspension feels a little loose, a little floaty, a little quick to understeer, and like it could definitely grip a lot better if I'm willing to sacrifice a bit of DD comfort.
In any hobby I've done, you start breaking the different variables down and then you break the variables into sub variables. You end up with a laundry list of individual parts that you have to improve on each one in order to improve as a whole. In tennis I have 35 items on that list and will pick 2 to focus on every practice session (usually 8-10x a week). In team roping I have 45, and that's only after I have my horse listening and executing on the basics.
I don't know what the list is for tracking my car but I'm figuring out the pieces as quickly as I can. But you start with car and driver. As for the car, you have safety, acceleration, braking and handling. Safety I'm limited by needing the back seat but have purchased a used racing seat to improve ability to stay in position.
While I had dreams of BBKs, simply upgrading the pads gave me more than enough stopping power for my level. So those are good for awhile.
Acceleration is a never ending addiction. I have no confidence is these engine's ability to handle additional power without a full makeover. I have plans for doing that the right way (FSI) on down the road but I need to make sure I still love this car a year from now before I shell out that kind of dough.
And then handling. I'm hopeful that coilovers, swaybars, and tires will give me the kind of grip I need for this car to feel "right."
The other main variable is me. I have to work on my lines, my car control, my steering, throttle, breaking and gear selection. I also need to know whatever track I'm going to drive well enough in advance so that I can memorize the lines quicker and start trying to execute on them.
I'm going to every car control, AutoX and track day that I can. While there, I listen intently and am the first to grab an instructor. Then I grab another after everyone else has had one. I ask to ride along with different drivers of different cars (Miata, GT3 etc) to understand how each one approaches the track and how their car brakes, handles, and accelerates and how that effects the line they choose.
So do I hope to get my tires right on the first try so that I can focus on other things? You're damn right. But if it takes me 5 different tries to find the setup that works best for me, so be it.
What I will say is that rear tires wear out so quickly, if you start with one of the popular autox street tires (Extreme Summer on tire rack) or a "streetable" R compound, can't go wrong. Don't like that set? You can try a different set rather quickly (sell of the fronts to help fund the purchase of the other set of tires).
One of my points and a pet peeve of mine is I see a bunch of guys always trying to squeeze the biggest wheel/tire combo as a trend. These guys often overlook or make a second priority of their driving, suspension settings, alignment, tire pressures. IMO, this is the wrong approach.
There's a a reason why Porsche didn't go any larger than the wheel specs I stated for their cup cars as well as sticking with the 245/305 wheel widths per the official cup car manual. You may or may not gain that additional edge past 305 on a 996 car but IMO, anything after 305 is a point of diminishing returns, not to mention fitment headaches that may not be worth it to some.
Also I'm a bit unclear on what you mean by 305 being an inch taller(taller than 275 assuming same sidewall aspect ratio?). Also just to clarify for others, these aggressive tire sizes may only work if you're running CO's. That's a very important factor to point out.
The Trefeos your running are 1.1" taller than my 315 NT01 unless they make some size I've never seen. And they cost 3 times as much. I agree with general idea of everything your saying, I'm just saying there is a very real, practical and adventitious application of the 315/30 18 NT01. And I should add they're not a headache to fit. I unbolted one wheel, bolted on the other. 18x12 +68 cheap OZ with -2deg of camber and plenty of room. No fender roll.
And by your same argument, Porsche never ran 305 on a c2. Porsche also never ran a VERY sticky 60TW tire on a c2. I bet it works a million times better than PS2s or whatever the OE tire is. Cup cars are a different animal. And I think (not sure) the tire sizes are based on racing rules more than anything else. They're obviously using different compounds. And comparing one manufactures 315 to another's 305 is REALLY splitting hairs. Your 305s (I hear Trefeos run really wide) are probably wider than my 315s.
In a nutshell, I love NT01s as a streetable track day tire for the reasons I stated in my other post. Best tire for my personal use. Within that tires available sizes, 315s are absolutely the fastest rear tire to set up a 996 c2 around.
Now aside from all that, how do you like the Trefeo R. I hear they're incredible and definitely would have ran them if I had the budget. How did they last/ perform?
I think we are saying the same thing, you're just referencing the NT01 specifically, which I failed to comprehend in your earlier post. Where as I was being more general. The NT01 certainly seems to be a great viable option as long as you're not one of "those purists". Lol.
The Trofeo's are way overpriced IMO but they were meant to go head to head with the Michelin Cups so in that comparison, it's not really outrageous. I happened to stumble across a used set for a song that still had a few track days worth left in them, else I wouldn't have gotten them truthfully. These were my first experience with a tire of this kind so I don't really have any solid references. My last track oriented rubber were the star specs. They performed very well but my review doesn't really hold any weight. It's like asking a guy that's only driven accords or camry's on what they think of a 996.
I've got a set of 305/35/18 NT01s in my garage I picked up when DiscountTireDirect ran the promo on eBay. I'm currently running Toyo 888 295/18s on 12" rear rims. I'm planning on installing the new tires soon. Reading this thread, it seems I should have picked up the 315/30s.
What negative aspects will I run into once I mount the taller 305?
Thanks.
I've run the same Toyo 888s as you.....in the past. Switched to NT-01 (although a 315) and my times plummeted. I suspect the only thing you will notice is a ton more grip.
Because it's taller, it's like making your gears even longer. There are also advantages to taller tires though (look at the 918 and new RS rear tires!). And based on what I've heard by most using r888, you will like those rears better. But on your next set try 315, you should notice a little better acceleration. Not mind shattering but I bet you notice it.
Got the new shoes put on today! 245/40/18 front and 315/30/18 rear NT01s on a used set of CCW C10 18x10et50 and 18x12et65. I had to trim some of the wheel well liner away but had about 9mm's clearance between the rear wheel and caster arm. Next track day is a week from Friday!
You ran 10s up front! Hell yeah. I have 18x10s being shipped tomorrow for the same tire. I was worried it might be to stretched. But check your lock to lock up front. Make sure it's not rubbing the brake line or thrust arm at full lock. I'm running a more aggressive offset. Car looks stuffed! I love it.
Edit: I'm pretty sure those are 8.5s up front. It looks more pinched on your wheel than my 9".
Crap, now that you say that I think they are actually 18x9. They measured 10" outside the lips. Sorry about that.
And they are mm's from my KW's. The extra 1" would have to go out if it was there.
That makes sense. Would you believe I bought these without the guy even knowing the size? He listed this tire setup on them on a GT3 and made me a smokin deal on them. I figured they would either work or I could easily get my money back out of them.
That's an awesome fitment, as long as everything is clearing. Definitely about the most rubber you can fit under a narrow body without body modification.
No, I called and left a message with WD but they never returned my call. Got them from RL Classifieds from a really good guy out Jacksonville. 18" GT3 wheels seem to be the ticket.
FYI, there is another set of CCW c10's for sale in the RL Classifieds identical to the ones I bought. These run about $3200 brand new.
https://rennlist.com/forums/parts-ma...-nb-black.html
IDK, how was your car before? My car was always pretty loose with 275s rear. Even on throttle which is not typical of 911s. It wasn't horrible but 315s should help. I just had a baby and it's kept me off track for a few months. So I've only been able to test on the streets by my house I typically use for testing when I make changes. On my car I felt really under sprung (550/650) and had tons of push but my fronts were really old with brand new rear 315s. I just changed to 650/850 and the car felt REALLY good BUT that's no alignment and I haven't mounted the new fronts yet.
So yeah, it requires adjustment but our cars are different. IIRC the rear springs on your v3s are ~1000lbs and the fronts are progressive. You should be able to dial in your car with some basic shock tuning when you get it on track.
My guess is it will be very 911ish. You'll need to point the nose toward the apex with a little trailing and add gas from there. Autocross (tighter corners) maybe more troublesome? I don't autocross so can't help you there.
Ok, sounds good. I had a some push with the stock setup on Super Sports then like you it was really loose at 245/275 on worn R6s.
I've got my alignment today and just trying to guess the best I can on how to set it up for my next track day in a week. I know Vandersmith is running middle setting on his sways and 245/315 but I'm assuming the C4S doesn't have as much natural push to it.
With moderate to plenty of negative camber, you should be fine. I get almost no understeer going in and sometimes a bit coming flat out of fast turns at the limit.
I guess one pet peeve of mine is with all the money KW is charging for the V3, you'd think they would at least come with some adjustable camber plates up front.
^But what else would you get? V3 is a nice shock and a chunk less than JRZs. Never driven pss10 but I'd take stock shocks over pss9. Unfortunately, I've found you get what you pay for with shocks.
Slakker, you'll need a front camber solution. Cheapest way is notch the tower, next is camber plates (which adds the benefit of a solid top mount), than split arms, than ERP arms. 0.5 drug of caster is quite a bit. If the castor picks are bad, maybe just find some gt3 arms...
It was only asshatting around on empty turns and twisty on-ramps but damn this setup feels good. The ride is a little bit rougher but the handling and responsiveness is insane!
OK, thanks jj1. You and johneecat have been a huge help on this project. There may be a clearance issue with the KWs and notching so just picked up some Tarret camber plates from my favorite place (RL Classifieds.). I'll try that route before springing for the GT3 control arms.
Dunno what you mean but at almost $4k retail, I would expect camber plates up front to be a standard feature IMO. Personally I think KW's are overpriced but they are definitely nice.
Here's the camber plates. Top hats came on the KW's. Can you tell if I'm good?
http://www.rennline.com/Sealed-Front...oductinfo/S20/
I got mine used for $2100. There's a group buy that was listed in this forum that had them for under $3,000. I agree they are pricey but they are very well done.
Well the way their picture shows it you may be fine. I always thought you want the spring>hat>and hat pivots off the shock mount bearing. But those pics have the spring just hitting the plate. Is your KW spring one of those conical progressive springs that gets wide at the end? Either way, probably best to just call Ira at Tarrett and ask how it should be used. I'll post a pic of my front shock from when I just had them off and you'll see what I mean.
I checked the area you mentioned was rubbing on your rear wheels. I have a good 10mm of clearance. Again I'm on +68 12" OZs. So either your fender liner is out of place for some reason or those wheels are MUCH further inset. BTW I just fit my 10" front wheels...
A182F5AC-300F-4B6F-9E92-D3F952C5AFAD_zps4ugkhfuu.jpg
I forgot to mention, it turned out to be a toe issue. Not sure if it was from the lowering, the adjustable rear toe link installation or all of the above. After the alignment, clearance from the thrust arm went from 8mm to 55mm. Wheel well liner probably would have been fine. Going to replace the liners for "stock" sake.
^Only other size NT01 makes I could try is 275. I could write a long thread about how to fit what on the front of this car but the 10 isn't that hard if your using coilovers and 245 tires. This is a +40 wheel with 15mm spacer (total et +25). I can't really drive it as is. Either need a smaller spacer or pull the fenders a touch or a little of both.
You have 10s up front?! I haven't seen anyone run anything but 8.5s. How do like it?
Front:
Toe - 0
Camber - -1.8
Rear:
Toe - .25
Camber - -2.5
He (my indie) really wanted to get -3.5 in the front but -1.8 is all we could get. The adjustable camber mounts will get it to -3.3 but not in time for next weekend. I'll then keep my eyes out for a used set of Gt3 control arms that would take care of the front camber and also allow him to fix the caster (.5 degrees off) as well. Or at least that's the plan.
But he's convinced this setup is going to push really bad. He's got a ton of experience racing 964's and working on and hauling the local cup cars. But I'm still hoping it will be more balanced than he's thinking.
I've got 105 minutes of sessions scheduled on Friday at Hallet and 175 minutes of sessions scheduled the following Monday at Motorsports Ranch. So I should have a pretty good feel for it after that.
I'm jealous. I've been having a hard time finding DE that will fit into my schedule. Let us know how the new wheel and alignment set up work!
Have you ever thought of doing alignments yourself?
The cost of all the equipment can pay for itself after you do an alignment or two. It's not hard, but you should have a professional shop set up the initial alignment, take the car home and take the camber, toe, and caster measurements using your tools and log them in a book. That way, next time you do an alignment, you just need to replicate the notes you took. If you do some research you'll find it's not difficult.
very interested to know how many other people are tracking the 996 on 17" wheels. benefits: lighter (generally), cheaper. Downsides: less tire (no wheels wider than 17x9 for a reasonable price).
If all I want to do is learn how to drive the car (not worried about lap times or wheel to wheel racing) it seems 17 is a very viable option.
thoughts?
