I like them a lot, but I would go 20"... NOT 21".

I have ADV1s on my 991 and I've been very happy with them. They've been good to work with as well.

FYI: I'm not certain if your car is a C4 or a C2. If it is a C2 they have had a set 5.1SL in narrow body fitment in their inventory for nearly a year now. I'm betting that you would be able to get a very good price on them. Unfortunately, they are 19".

http://www.adv1wheels.com/blog/inven...1sl-monoblock/

 

thumbs up on the shoes!

 

OK... I'm torn now... 20" or 21"....

I do have a C4S, if that puts things more in perspective.

Lets take a vote! 20" vs. 21"

 

20s. Already fill in the wheel arches perfectly.

Why do you honestly need to go any bigger…..

No matter what size you go, get a quality forged wheel, it won't warp or bend as easy and there are meaningful weight savings.

Im also not a huge fan of these "boutique" brand wheels. BBS, OZ, Volk, Neez….the real deal. Forgeline makes a great wheel, then after that Id consider HRE and GMG. You really can't go wrong with any of these brands IMO.

 

20 inch .. 21 is totally un-necessary

 

From my understanding ADV1 makes one of the highest quality forged wheels. Lightweight.

Have I been misinformed. These are not cheap by any means, so I don't want to be dooped!

 

You have.
If your don't like the styling of say BBS, Volk, or NEEZ. You are far better off going HRE, Forgeline or GMG then ADV1.

Forgeline makes a great wheel at a good price.

 

those are really nice! post pics on the car if you pull the trigger.

 

What would the offsets be on your proposed set up?

FYI OEM for the C4S:

Front 8.5 x 20 ET51 - 245/35 ZR20
Rear 11 x 20 ET52 - 305/30 ZR20

 

I believe the rear wheel is 10.5" unless it's the Sport Techno wheel which are 0.5" wider.

 

If you are going custom get 9 or 9.5, for the front.
Wider is the best way to bring wheels flush.
Factory 9" is 51mm, but a 49mm would be more flush.
I believe a 9.5" in 46-48mm range would work.
Someome was trying that, and I hope to hear how it worked out.

I dont think anyone here will vote for 21".

 

Normal rear is 11".
Sport Techno & 50th Anniv are 11.5".
GT3 is 12".

 

Thanks for letting me know.

Anyone think 12" is overkill for non GT3 or non turbo cars? A lot of aftermarket brands are only making 12" for rear.

 

12 is fine. Only think to consider is tire width. The GT3 has same 305's as 4S so 12 will work with that width. If you have 295's don't think you can go 12" or if you do get new rear tires to fit.

 

I fine the balance of the car is good as it, so adding a 12" rim might induce more understeer. I track the car a fair bit.