Hi im new with Porsche and my first car from Porsche 992 and i will get my car next month from dealer.

my question i ordered vossen rims HF 5 20x9 21x12

but is the S lower then the base model ?

and do i need lower kits ?

 

No, it's exactly the same.
The diameter of the 19/20 and 20/21 wheels is the same.

 

I don't think PASM (10mm drop) is available on the base Carrera.

 

Being an owner of both sets of wheels, they’re not the same. In fact, the PCM has a setting to select 19/20 and 20/21 wheels to accommodate the difference in circumference. My 19/20 winter wheels are the Base Carrera wheels. My summer wheels are 20/21 Spyder Design wheels.

 

Yep. Setting aside SPASM, Porsche’s web site claims the same 51.1” overall height for both the Base and S cars.

 

my bro if u send to factory they will add it for you my car they added it for me

 

I am confused. You state that this is your first Porsche and that you’re getting your car next month. Are you saying that Porsche added it after the fact? Or that you got them to add SPASM to your Base Carrera.

 

from factory they will add it (10mm) because my car will come with Aerokits so i will get it in February

 

You can always just get a techart spring after the fact.

 

its fit in base carrara ?? i think only in S

 

In fact, the OEM 21'' REAR tire vs OEM Winter 20'' has the same diameter (delta 1mm = 0.3%). Front tire OEM 20'' VS OEM Winter 19'' have an outside diameter delta 9mm = 1.3%

 

Is that from actual measurement or calculated?

 

I went to the garage and measured my fronts. My summer 20" fronts with OEM tires (26 1/4") are nearly 3/4" larger in diameter than the winter setup. A properly inflated low profile tire isn't sagging 3/4" with the weight of the car. Of course, proper measurement would be both tires off of the car, but that's not worth the effort. It's not the "same diameter" or "delta 1mm".

I don't feel like unstacking the fronts to measure the rears, but you can bet that the delta there is even bigger. The bigger wheels are bigger, even with tires.
Side note: Porsche claims the same offsets for the Base Carrera wheels and the 20/21 wheels, but they're clearly different and obvious when installed on the car.

 

But the overall diameters between the winter/summer tires are the same. All the tires charts give the same out.dia. between 305/30-21 and 295/35-20. it’s the perfect match and same thing for the front tire size. But between summer tires and winter tires there’s certainly a difference because the winter tires have a more depth tread than the summer tires

 

Yet, the summer tire/wheel combo is larger in diameter than the smaller wheel winter tires.
Aside from how the tire fits to the rim, the tire size isn't going to give you enough information to establish the overall dimensions of the tires. You can have two tires that are the same "size" from different manufacturers, but be different in overall size and shape -- especially when it comes to the sidewall design. In lowered applications, one brand of tire may rub where another brand may not, even tires ostensibly of the same size. Heck, if you want to complicate things, a 295 tire can fit on a rim that otherwise takes a 305 and the result would be a different profile.... and we haven't even touched the stretching community. :P