Boxster Tires

[blakebastain]

I have been trying to find a good answer to this question via private messages, but I can no longer track all the answers. Hopefully by starting a thread I can get a better count of the suggestions and advice and finally make a decision.

I drive a 1999 Boxster, the 986, with a 2.5L 201 HP engine. It's also my daily driver. I'm currently driving on 18 inch wheels, and the cost of tires is killing me.

I shopped around and found a nice set of stock 17' rims for $325, straight, few scrapes, but perfect for my needs. (I'm sure you can see where I'm going with this.) Now I can have a set of race tires for AX, plus a set of (substantially less expensive) daily driver tires.

There are a few considerations with buying tires. In no particular order: Consideration #1: money. If I don't lower my AX expenses, the honey-do list my wife will create will kill me. Consideration #2: The new Zone 8 AX classes. No matter what class I'm in, I'd like to spend all my available points. And, Consideration #3: I do want to do what's best for my car and my driving style.

So, here are my leading options: (With a little math thrown in.)

My Boxster starts at 295 points, plus 25 for the mid-engine bonus, so 320. That's 30 points 'wiggle room' to be in CC14, or 80 points to be in CC13.

Set Up A: Hankook Ventus, treadwear 140 (+20 points), Front 215, Rear 255. Cost: about $560
Set Up B: Hankook Ventus, treadwear 140 (+20 points), Front 225, Rear 245. Cost: about $570.
Set Up C: Dunlop Direzzas, treadwear 200 (no additional points), Front 225, Rear 265. Cost: about $680.

So, really, two main questions, plus an optional 'what if' question:

Question #1: Will having treadwear 140 tires make up for the difference in tire size?
Question #2: With only 201 HP, is it better to have more rubber up front for steering or more rubber in the back to push me around?

Optional #3: Or should I even be worried about car class? I could probably get a set of 16" rims and stay in CC14. Or I could put enormous tires on the 18" I have, save my 17s for daily driver tires, and run in CC12.

Let the advice begin.

[Kim Crosser]

I wouldn't see much advantage to going with 265s in the rear, and the 140s *should* be more effective than the 200 treadwear tires, so I would drop the Dunlops as an option.
My $0.02 on the Boxster is that there isn't enough torque to really break the rears loose, so bigger rear tires are just going to add unsprung weight. With the relatively 50/50 weight distribution you don't really need a bigger rear contact patch.
Of those three setups, I would choose B - get more tire up front to help the Boxster with turn-in. With a stock 205 front and 255 rear, the Boxster has a reputation as wanting to understeer. While that isn't true if driven right, it does take a bit more work to rotate a Boxster than a 911. More front rubber should help.

[Greg Phillips]

I would vote with Kim on this one.

Go to 17" wheels and the 225 front and 245 rears (or even 255 if points permit).

The 16" wheels won't be much good unless you want to use 225 tires all the way around. Not many tire options for 245 and larger for the rears.

Greg

[Greg Trigeiro]

How wide are the 17" wheels you are buying? Will they work with the tire widths you are considering?

For track tires I am using 17" wheels on my 996 for the same reason. Even the Nitto NT-01 tires are a cheaper in 17" than 18" for the same width tire. Same with Hoosiers and Kumhos if I wanted to use them. Both the 17" and 18" tires for my car have about the same tire outside diameter because the aspect ratios are different. Thus the electronics don't get confused.

[Steve Grosekemper]

Forget the 16 inch option. there are no usable 245-16's that are not R rated.

225/255 or 225/245 depending on points available.
225's are the max size for a 7 like you have in the front.

Option A: (My choice)
I would do Hankook Ventus R-S3's in 225/245-17.
This will give you increadible turn in and a 2.5L Boxster doesn't have enough power to spin the rears out of every corner.
These are really nice tires.
I added photos so you can see the larger blocks on the outer edge of the Hankooks. These will get torn up less on super twisty tracks when you don't have enough front camber.


Option B:
The Direzza is 225/255-17's
The dirrezza's are the #1 choice for 200 TW SCCA showroom classes.
They have great stick and excellent feedback.
Oh Ya, they wear like iron! So you will likely get significantly more laps out of them.
But at 20% more cost you would have to get 20% more laps to break even.


CC14 is the place to be.

I know, not much help.
BTW- A proper alignment will get the most out of whatever tire you do decide to use.

[ttweed]

No matter what class I'm in, I'd like to spend all my available points.

If you are interested in optimizing your car for a certain class, don't do anything until the Z8 rule proposal process is complete this fall. There are proposals to change the penalty points for different classes of tires, and you will not know how much a particular type will be penalized until they settle on a scheme for next year.

TT

[frequencydip]

Just did the same thing but with a 987.2 Boxster S. I ended-up going with 17 rims (they fit on a S just be sure to upgrade brake ducts) and the RS-3 tires 255 square. Thats plus two sizes in the front and minus one size in the rear. This makes the car really easy to turn in and rotate, no understeer and just a bit of snap oversteer if you dont unwind early. I dont have issues spinning the rears under power unless the exit is very choppy the 140 treadwear holds the tires firmly..

[Kim Crosser]

I ended-up going with 17 rims (they fit on a S just be sure to upgrade brake ducts) and the RS-3 tires 255 square.

255 all around, with 120 treadwear, means you just took 120 points in the new GGR rating system. That is at least two classes up from your base.

[frequencydip]

Yes it puts me in CC9, I'm 585 points with stock size tires or 595 points with 255 square so I'm in CC9 either way..

[rshon]

His stock setup must be 235/265 on 18" wheels.

I have to say that the 255 "square" setup (same size tires and wheels on all four corners) is a great way to eliminate the push on the stock Boxsters (and Caymans) at an AX; it's especially fun on the tighter SE lot courses. A side benefit is that it allows you to rotate tires front to back to even out wear. But you will need to buy another pair of 8.5"x17" rear wheels for the front...

[Cajundaddy]

Ahhhhh 17" Boxster tires. One of my favorite subjects. The tire rule change for next year will be important but with narrow differences within classes you will probably be competitive as long as quality tires are your first choice. I have run several different setups over the last 4 years and for AX I favor a 255 square. It is easier to rotate the car and you have higher ultimate grip. The ability to rotate tires to all four corners is also nice to maximize tire wear and tire life. When running on a stock set of staggered wheels I run 225/255 to good effect. The staggered setup may be a shade faster on some big tracks like Fontana Roval but in AX I expect square is always faster. If you want to stay on street tires the RS-3 looks like a winner. Whatever you do don't get R-comp tires. It is worse than a cocaine addiction. Just ask my "You need ANOTHER set of tires???" wife.