How much tire do I need for a time attack car.

I have a focus st, that is pushing about mid 400 in hp and tq. The weight is about 3200 with me in it. The car is for time attacks so I might not really need maximum width. 

The set ups are all using NT-01 

18x9.5 all around set up with 275/35/18 and 245/45/18 set up - This set up cost $1200 for off the shelf wheels. 

The second set up is 

17x11 F and 17x9 rears with 315/35/17 245/45/17 in the rears. - This is a custom set up and the wheels will run $2600

The tires weight a bit more in the second set up about 2lbs increase each corner, rim weight will also be about the same 19.2 lbs for the 1st set up and the second set up will probably be 20lbs front and 17lbs in the rear. 

What do you guys think. 

Depends on how competitive you want to be. 

Basically all the successful Time Attack builds are ALL OF IT as far as power, tires, aero, etc. If you aren't building to the limit of your class, you aren't going to win. 

There is serious money going into TA cars these days.

Yeah your right about that one, but my car is in the limited class and it does pretty well already. 

But the reason I ask is because KTUNE TA Integra runs pretty narrow tires iirc they run 285 in the front, that is one of the fastest FWD and unlimited car and they look like they spent a lot less money then rest of the people there. Their weight is less thou maybe 2100-2200 without driver and I think they have like 600hp and 400tq. 

So that is a situation where the widest tire they can fit, was not the case. The reasons I believe is because the extra aero that was needed if the wheels poked out of the fender, would have increased drag. 

But I also track only around my socal, so not a lot of high speed tracks here with long straights. 

I'd probably lean toward as much mechanical grip as you can possibly get then. 

I think the Vorshlag guys showed on both their FR-S/BRZ, and their Red Mustang with the same power/weight they always got faster with more tire. So a heavier FWD car with a good amount of power, I'd think you'd want as much tire up front as you can get on the car. 

The real proper answer is "You won't know unless you test both setups." But I realize thousands and thousands in testing isn't really feasible for us average enthusiasts. 

Yeah my impression, after looking at what does well, is that if you aren't throwing cubic dollars at the car/support team/driver, it's not going to be on the podium. Most of the cars are built by shops themselves as tax write-offs, not by individuals. With their reputations on the line, they tend to go all-in. Yes I know you're in a limited class, but still. The cost aspect of it took all the attraction out of it for me.

I think the 315 Front say 285 rear setup may be your best option. Your going to have to flair the car out a good bit but its a TA car so it should already have a decent flair on it right now.

I am running a 315/355 setup on the ACR when I went out for fun and I got spanked HARD, more about the lack of traction then the lack of driver. Also I suck at TA.

Ktune didn’t have to spend as much as others #becauseHonda. 

Side question- is there any money in TA? It can’t be enough to recoup any of what avehicle outing costs, right? I thought TA was adverts for sped shops. 

I think there's about as much money in TA as there is in club racing...

Lots of mechanical grip is good, but you also have to look at the format - are you running in the Japanese format where you only go out for 2-3 laps at a time, or are you running 15-20 minutes each time?

For the former you probably want something close to an Auto-X tire that warms up quickly (and possibly less tire to warm it up quicker), for the latter you probably want more tire.

And depending on how far near the pointy end you want to run, you very likely will have to look very closely at aero.

I wouldn’t even consider TA without aero. Unless there is a class for that... seems sketchy to run triple digit speeds without some form of aero for stability. 

American, so I am siding with running 315 up front with a custom set up. 

There is no way I can run 285 on the rear, the only reason the front fits is because some suspension changes that were done to get -4.5 camber.  The car is also flared out with the fenders being spaced out a bit. 

Everything else is done to it, splitter, wing, canards

Can you bring the splitter out far enough on the sides to make some spats to cover the part of the front tires that will be sticking out of the fenders?

Already did, more like front flairs then what i think spats are lol. I think spats are when you cover like half the wheel. 

I would agree with the comments about "all of it"

Within our local series the Gridlife Time Attack series we have yet to see anyone move to smaller tires and go faster, people keep moving upwards in tire size and going faster and faster. The unlimited evo's are running 315's now and we did some personal testing with a 3200lb e46 m3 on 9.5's and 275s vs 11's and 285's and went 2 seconds faster on the same track back to back sessions.

When looking at other cars try to look for reasons why they're running what they are.

In James Houghton in the K-tuned integra runs the 285 Pirelli DS slick, which is already relatively tall at 25.3" diameter for an integra. The only sizes bigger than that are all 1"+ larger overall diamter which would hurt everything from aero effectiveness to center of gravity to gearing. 

In your limited Class the K-Tuned civic of Chris Boersma is running the 295/25/19 Kumho V720 ACR tire off the viper. Per the "time with attackers podcast" He's convinced despite it's 200tw rating it's faster than any of the 100tw stuff. While you could again make the argument that he's "only" using a 295, his only other option in that compound is the 335/30/19 which is nearly 3" taller diameter and not really practical to fit.

I did see that Houghton put an entire wider front end on the car this off season so perhaps they are preparing to move to something even wider?

Out of curiosity are there no wider 18" wheel options available for you? the 315/30/18 nt01 is a touch shorter/lighter than the 17" and it seems these days 18" wheels are more popular which would leave you open to more options down the road if you decided to move from the nt01.

oh, and because I forgot to ask in my long post, do you have any pictures of your car you'd be willing to share? I got into the automotive hobby with a Ford Focus so they're a sweet spot of mine.

5x108 is the worse bolt pattern to have, I have no options other then to go custom. 

I went with 17 custom as an option because its cheaper to have less rim, and smaller tires, but they both hover around 25.5. The weight is about the same for 315 in 17 and 18s. I can always fit a 275 on the 11 inch rim and see how it test compared to the 315. 

18s do have more options but they are the standard maxed out at mostly 285 and one 295, I can get a 315 with nt01 and they probably be the same size as they do run more narrow. 

I’ve been pretty happy with NT01, how long they last, how they handle. 

ALL THE TIRES!

What class/events are you running? 

To me, that those wheel and tire setups will put you in unlimited FWD classes in most TA formats. Which, I hate to break it to you will be INSANELY uncompetitive with that power/weight/chassis/aero. 

I wouldn't worry about the weight too much.  

And discounttire on eBay has a $100 off of $400 sale right now.  Saved me $200 on a set of nt01's for my z06

regarding op, I'd go largest tire you could 

klodkrawler05 said:

oh, and because I forgot to ask in my long post, do you have any pictures of your car you'd be willing to share? I got into the automotive hobby with a Ford Focus so they're a sweet spot of mine.

My first tuner car was a Focus as well, would love to see pics for sentimental value if nothing else.

TheRX7Project said:

klodkrawler05 said:

oh, and because I forgot to ask in my long post, do you have any pictures of your car you'd be willing to share? I got into the automotive hobby with a Ford Focus so they're a sweet spot of mine.

My first tuner car was a Focus as well, would love to see pics for sentimental value if nothing else.

Third for my first real hobby car being a Focus. I loved that car. 

This might be the first time I've seen 285 width tread and narrow used in the same sentence. 

In reply to Appleseed :

RIGHT? I won't lie, if the funds where there I'd have a set of 18x12's and 335's on the rear.

How much tire do you need?  Not sure, but you will want more than will fit

It's even the right color :) my Focus SVT was sonic blue