johnwb

I have a stock 2005 997S and I'm planning to buy a set of wheels and tires for DEs.

My current tires are Michelin PS2.
Front 235/35ZR19
Rear 295/30/ZR19

I was thinking of 18" factory lobster forks or something simple like that with Toyo R888.

Anybody know what size tires I should go with to keep the speedo and tire diameter correct? Thanks.

mdrums

a member over on the GT3 forum is selling some CCW wheels. GT3 and Carrea are same fitment.

I and many other use the forged CCW wheels.

I suggest
9x18 front
245-40-18 Toyo RA1 or R888

12x18 rear
305-35-18 Toyo RA1 or R888

You will not be able to fit these size tires on stock 18" Porsche cast wheels. Also the "Lobsters" are 19" not 18".

brendo

^ i thought they made lobsters for the base carrera in 18" ?? must be wrong.

i use 19" lobsters because they were cheap and the lightest OEM wheel.

i'll probably end up with some super light 18's this season...

mglobe

I'm an advocate for using inexpensive Porsche wheels for DE's. Yes, they are not the lightest, but you can find a set of Turbo Twists, or 5-Spoke 8's and 10's X18 for $1000-$1500. Shod them with 245/285 or 295 tires, and you will be in very good shape. I would try to get as much tire on the front as possible to help cure the typical 997 understeer. You might consider Nitto NT-01's instead of the R888's. They will last longer, and in my opinion are grippier too. Only downside is they don't work very well in the rain.

What level of driver are you?

johnwb

Thanks for the suggestions.

In my PCA region I'm a level 2 of 4. That's means that I'm not dangerous and I don't hold anybody up. I only have 6 DE days to my name so far. Lots to learn.

I will be lucky to run 6-9 DE days a year so I was figuring 18" Porsche wheels will keep things less expensive for me. My goal is cheaper, stickier tires. I'm going through PS2s fast.

mglobe

I think you have a good plan. I made the mistake early on of buying expensive, lightweight, 19" rims. Hate to see others go that route. Be aware that depending upon which wheels you buy, you may need to put spacers on. I bought 18" turbo twists for my 997S, and had to buy 5mm spacers to push the spokes out far enough to comfortably clear the brake calipers. The issue was the offset, which unfortunately I don't remember at this point. Not a big deal though, and you car will look better with the spacers anyway.

mdrums

mglobe, you can find a used set of CCW 9x18 and 12x18 for right around $1800. These would provide a much better size for DE use than the smaller stock 18" Porsche wheel. The use of CCW's is not really based on any weight savings as they are not the lightest forged wheel but they are super strong and in the correct size to get the same overall outside diameter when you use the size tires I suggested in my 1st post.

johnwb, 6-9 DE's a year is a nice amount so I highly suggest you get some wheels in the correct size so that next year or later this year you are not looking for another set.

str8ner

I have a set of wheels from CCW. I used them on my GT3 and my 997 C2. 9.5 or 9x18, 12x18. R888 on them. Front has decent tread while the rear need to be replaced.
PM me if interested.
Stephan

p-cardriver

I have a set of 18" Porsche 5-spoke wheels that were used for DE and are now for sale $800 plus shipping from SE MI. I used Nitto NT-01 tires last year and was going to try R888 this year. Wheel sizes are 18x8et57 and 18x10et58. They fit with no problem on my 2007 997S. PM if interested.

I also have a spare set of 19 lobster forks that I was going to clean up, paint black and try at the track this year - but my DE career has ended for a while so those also are for sale, same price.

p-cardriver

http://www.nittotire.com/#index%2Etire%2Ent01%2Esizes gives you the specs on the Nittos - there is a similar site from Toyo for sizing on R888, and you can also find the diameters of the stock setup for comparison.

Alfaguy2

Whay about the tyres on this 997 - great for reducing your carbon footprint.

http://www.youtube.com/watch?v=GaQB_...layer_embedded

mdrums

Guys...if you are running a C2S...it come stock with 19" wheels tires that are a certain circumference and width. You will want to match these specs overall. 18" wheels and tires work great at the track but going with a smaller diameter and overall foot print is not something I'd do by using 8x18 and 10x18 wheels.

This is why I and many advise to get either 18" wheel that will properly accept 245-40-18 and 305-35-18 tires or get another stock 19" set of wheel/tires in the stock sizes.

p-cardriver

I agree overall - although 295 is a correct rear size for the 997S as well, and I think 275 is allowed (for winter) on 18 inch rims so as long as the load rating is acceptable they are ok. The disadvantage of course with the narrower sizes is less rear grip, which as a beginner/intermediate student I liked (also offset the tendency toward understeer). I was focused on learning car control, which I don't learn as well if the car won't lose grip. Now that I've got that down better, and I'm driving at an advanced level, I am pushing the tires too much and need to get the wider rear rubber on. That's why I bought the 19 inch wheels - but now that I'm not able to go to the track any more both sets are for sale.

Tire and wheel variations from factory spec (in the owners manual) need to be made carefully and with a lot of input and thinking. This is no place to take risks, or expose others to risks, that you don't understand. Same for varying pressures.

cbzzoom

Hmm I was going to post my own thread on this but I guess I'll just jump in this one.

I've been trying to figure out what size 18" to go to. I want it for street + occasional track cuz I'm sick of the stupid 19's.

Anyway the sizes that I've found that make sense are :

235/40/18 + 295/35/18 ; ratio : 1.028
ideally on 8.5" front , 11" rear
- OEM 18" size though they run it on 8" front rim which is too small IMO

245/40/18 + 295/35/18 ; ratio : 1.016
ideally on 9" front , 11" rear
- not as much rear to front size difference, which lifts the nose a bit

245/40/18 + 305/35/18 ; ratio : 1.027
ideally on 9" front , 11.5" or 12" rear
- great size, but these are available in drag/slick tires only

245/35/18 + 315/30/18 ; ratio : 1.028
ideally on 9" front , 11.5" or 12" rear
- good ratio match but quite a bit smaller total diameter
- effective down-gears you, also not as much sidewall as 40 profile front choices

mglobe

In my opinion, the front to rear contact patch ratio on the 997 is set up to minimize the possibility of oversteer. Out of the box, the cars push pretty badly on the track. With sufficient front camber, you can get rid of this, but it's hard to get that much camber without adding either camber plates or GT3 control arms. Alternatively, you can go with a wider tire up front, which is what I recommend. I don't think matching the stock tire circumference is all that important, unless you're really concerned about the accuracy of your speedometer/odometer on the track. FWIW, I race my Spec996 on 245/285. I've also run it with 245/275 (Nitto's), and it works quite well with that combo.