mdrums

Yes wheel enhancement told me the 997 Carrera III wheels rear offset is 51. I can use anywhere around a 60-67mm offset from what I've been told. they are not positive this 51mm offset will work with 315 or 305 rears.

What confuses me with offsets is my stock 19" wheel is a 67mm offset BUT it is 11.5" wide. These 18" wheels with a 51mm and 60mm offset are only 11" wide. I know wheels width and offset somehow work together in fitment.

I am also interested to find out if the 996GT3 wheels will fit or the Sport Techno. I am just looking for the strongest, lightest least expensive wheel I can find.

NJcroc

an easy way to visualize this is get a ruler. the offset is millimeters away from center where the wheel meets the rotor. lower numbers are closer to center of wheel so they stick out further in the wheel well. higher numbers mount closer to outside rim of wheel moving the rim in to body. this is best till you have clearance issues on other side. another thing to remember is that offset doesnt matter of rim diameter only width. a 15 -20 inch rim would have the same offset. as long as width is the same and height is close.

I doubt a 996 gt3 rim would save any money as these are highly sought after to regular 996 owners because of the increased width(they dont fit anyway)

CCW makes a great rim and the volk wheel you mentioned is also a great choice. with the CCW whell when something goes wrong you can buy a replacement or get it fixed as gary seems to be doing now

mdrums

Another thing (my wife brought this up today at lunch) is for the coast of the Bridgestone RE050A Porsceh N Spec I just bought in 19" for the street to replace my worn out 19" PS2's that came on my car it will just about take me 3 sets of the Bridgestones ($1200 w/tax, shipping and mounting) to break even with 1 set of 18" wheels and tires. It's just DE's and a few AutoX's for fun so that is something to think about...what do you all think?

RonCT

Nothing wrong with that logic. Today's summer tires (especially the PS2 and Neova) are yesterday's R-comp equivalent. No problems with cold, rain, extreme wear, etc. You give up a few seconds on a long track, but gain more feedback and progressive break-away. When I had my M3 with 265x4 PSCs, I seriously thought about getting 4x PS2 when the R-comps wore out because I often had to leave the PSCs home because it was 28 degrees, was raining the day of a DE, etc.

I think many people put too much stock in R-comps and as you say, this is for AutoX fun and DEs...

mdrums

Ron, that is what I am kind of thinking too, however here in Florida it does not get that cold to effect my DE or AutoX days with R compound tires like the Cups or RA1. Part of me would like to experience R compounds and 18" wheels on my car though. I just do not have the extra money to experiment like some do on these boards with all sorts of tires and wheels and I have to make the correct choice the 1st time.

sig_a

I just went through the same thing two weeks ago. I worked it out using advice from the following well established companies. I have a 911.

Great help from Lingenfelter Performance (Corvette folks in Decatur, IN) where I bought a set of 4 FIKSE FORGED at better pricing than Wheel Enhancement. Fikse customer service 800 number will answer your questions about offset and tire size for your specific application. They know Porsches well. Lingenfelter is also a Michelin dealer and will give you a tire/wheel package deal.

Click on Lingenfelter.com

Click on Fikse.com US Manufactured

Also check out Nittotire.com US Manufactured in Georgia

Also check out: http://www.miata.net/garage/tirecalc.html to help you calculate tire size and fitment.

mdrums

Well took the plung today and ordered up my CCW wheels and Toyo RA1 tires. The CCW guys suggested 18x9 and 18x12 wheels and 235-40-18 fronts 305/35/18 sized tires. Rims are widered than I expected but they said this is the way to go. I wanted black rims but they were honest with me and said the black anodizing will fade or turn purple after a while so I went with the stock look. I will post pics next week and a report after my September 15th DE. Hope I'm making the correct choice!

see ya

Gary R.

Good choice, CCW makes a great wheel!

LVDell

They (CCW) had them in stock??? 12 inch for a 305? The proper size (optimal) for a 305 is 11" not 12. Not sure what's with the advice they are giving. Sounds like maybe they had 12's ready to go but NOT the 11's you need???

spare tire

Pilot Sport Cups are a great all around tire. You will love them. 18" wheels allow for a much bigger selection of tires. What ever you do, do NOT try 315 Cups on your car. I know of three people who did. They will fit and not rub to much. The big down side is tire roll in hard cornering. Two guys were very pissed off when they corded in two or three sessions and had to watch all of us run our GT3s in perfect weather. They came to the track with new tires and brought no backup rubber. The GT3 has 11" rims in the rear and 315s are listed as the smallest rim that will take them. Get the standard 295s and 235s.

RonCT

Hmm... I checked with multiple wheel builders and / or sellers before purchasing and every one of them (including CCWheel - just checked my old emails to confirm) said 8.5 x 18" front and 11 x 18" rear is the proper sizing for 235-245 front and 295-305 rear. Fikse ended up building my wheels and they are 8.5x18 and 11x18. A 12" wheel is really too wide for the 305 -- per Toyo's web site the optimal width is 11", and 12" is on the very edge of acceptability. One question to ask when buying wheels that are wider than necessary is why you would want the added weight and cost for no benefit.

NVRANUF

I just installed 18" Victor rims with 235 and 315 PSC's (what was recommended) this past weekend at the track... never had any issues on my first DE event using them..... other than trying to get a handle on R compound vs street tires

spare tire

I am only refering to MPSCs on 18" 996 GT3s. If you drive hard they will cord.
315 Hoosiers are ok. I do not know anyone who uses toyos on a GT3. Road America had 40+ GT3s yesterday and most cup cars were on Michilin slicks,996s were on MPS cups or Hoosiers or PS2s and the 997s were on MPSCs. It might be differant in other parts of the country. I do not care what some race shop told you. I saw 3 people with corded tires with less than 3 hours on the tires. Not three track days. One guy got three sessions and they corded. He missed the last two sessions. The 295 MPSCs I use cord in 36 to 50 sessions.

Gary R.

I run 315's on 11.5" CCWs, seem to be just right. I'm surprised you aren't going with 245's in front though..

racewheel

per toyos spec sheet http://marktg.toyotires.com/file/30029.pdf
"Bold designates measuring rim width"
this is not indicating optimum or recomended rim width, only that that is the size wheel used from which cross section was measured
rule of thumb for optimum tire performance and life is that rim width should meet or slightly exceed tread width, in this case the 305 35 18 r888, tread width is approx 11.7"
john