[stevev968]

Hi guys,

I am about to buy a set of 18" wheels for my 968CS.



Originally, I was going to buy the 3 piece RH replicas of the Speedlines. However, after the discussions about how soft the outer rim was and poor tire beading quality, I'm now looking at a set of Dymag's from the UK since they're not so common on road-going 968's (pic attached).



I have the 17x9 and 17x7.5 CupII 's on the car currently with 225 and 255 sized tires.



What width should I be buying in 18" and what offsets (ET) specifically ? What tires would be correct for these wheels?



I was thinking 18x8 front and 18x10 rear???? The car is equipped with M030 so is lowered, hence I don't want tires rubbing.



All help appreciated.

Regards,

Steve

   

Partial Post: Please Login or Register to read the full post.

[flash]

"correct" is a somewhat subjective term



when i went to HRE for the fit check at the plant, and had them build wheels specifically to fit the most rubber under my car possible, a few factors were involved in making the determination of offset:



what brand tire do you want to run? widths vary as much as an inch from brand to brand, even within the same "size", so you can't just say "285/30", and expect it to fit - you need to know the actual outside width dimension



what camber angles are you going to run? this can make for some rather significant issues in max width, as it can move a tire closer to an interference point



what is the ride height?



with my car, at 1.75" lower than stock (M030 is only 20mm), running 1.5 degrees of negative camber up front, and 2 degrees negative in the rear, with bridgestone S0-3 tires, they came up with the following:



18 x 10 rear ET 52 running a 285/30/18



18 x 9 front ET 57 running a 255/35/18



they do not rub under any condition so far, and i do not anticipate them doing that either



the extremely large front tires do present front tracking issues, so be careful about that one



the extremely large rears do lift the outer corners off the ground sitting still



hope that helps

Partial Post: Please Login or Register to read the full post.

[BruceWard]

Are these custom ordered wheel where you will be able specify the exact width and offsets? If not what are the available options?



Dave has a "Wheel Fitment Calculator" on his website http://968engineering.com/technical.html .

Partial Post: Please Login or Register to read the full post.

[stevev968]

Thanks Flash and Bruce,

Wow, I didn't even think about tire widths and camber.....



My car is standard M030 and I was running Bridgestone RE55S (I'm not sure if they are available in USA).



I don't need to go too wide .. I would be happy with 245 (f) and 265 ® , but again as Flash said it depends on the specific tire.



They Dymag guys told me I can order anywhere between 8" and 13" widths , but have not indicated offsets available.



I'm looking at Dave's wheel calculator. Do you guys know what the offset is on the 17" Cup II's (ie. the 993 numbered wheels) ? I think they are ET 65 front and 55 rear.



Regards,

Steve

Partial Post: Please Login or Register to read the full post.

[BruceWard]

Offsets of 65 front and 55 rear are correct for factory 17s.

Partial Post: Please Login or Register to read the full post.

[Eric_K]

Mille Miglia makes 18x8.5 et52 and 18x10 et47 CupII style wheels. I think those are good sizes and offsets. I had them on my M030 968 with no rubbing issues. The Dymags would be much lighter than the Mille Miglias.



The RHs are high quality wheels. The outer rim is not softer than any other wheel of similar construction. I have never had any issue with mine. If forget their offsets.



Eric



       

Partial Post: Please Login or Register to read the full post.

[flash]

those rears definitely would have rubbed on my car with my setup

Partial Post: Please Login or Register to read the full post.

[stevev968]

Hi again,

Need some advice...

What offsets would you guys recommend I go for if I'm looking at 18x8.5 and 18 x 10. ?

I'm a bit confused as you can see...

Regards,

steve

Partial Post: Please Login or Register to read the full post.

[Jason Judd]

I'm running 9.5" and 11" for my 18" rims...No rubbing whatsoever.



I'm probably getting new wheels this year. Currently I have CCW's. I'm considering the Fikse Profil 13 or the Fikse Mach V. Fikse said they would have no problem building them for my car. BBS would be a little too much for my pocketbook.



My car is stock...except for the mods I've done.



Jason

Partial Post: Please Login or Register to read the full post.

[flash]

steve - there is a range, but to do this right:



you HAVE to choose a brand and model of tire first - then you can work with sizes - that will give you the actual dimensions



then you have to figure out where you want your ride height and camber angles



then you can see what wheel will fit, based on the space remaining



you can definitely get them to fit, and you will have some choices - do the steps, and it gets pretty easy

Partial Post: Please Login or Register to read the full post.

[stevev968]

thanks Flash and all,

Appreciate the feedback... I'll look into tire combo's etc.

Regards,

steve

Partial Post: Please Login or Register to read the full post.