When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have searched the prior posts and continue to be confused. I am a newbie to this issue. I have a 2013 Porsche 911 Carrera S cab with 20" wheels. I want to purchase aftermarket wheels. I will be running 305 tires on the rear and want the wheel to set closer to the outside of the wheel opening. Do I use a spacer or is there a custom offset on the new wheel that is better? Sorry for the dumb question, but my research has not yielded an answer.
Depending on wheel manufacturer you go with I think each has its own proprietary setups? You let them know if you want OEM fit or if you want it FLUSH, TUCKED etc they can custom make it for you.
I know for OEM wheels folks go with spacers to get that close to flush look to the wheel fenders maybe like 7 and 15 mm spacers? The experts here will chime in soon. I'm just saying what I've read and heard.
Not dumb questions at all. It’s dumb not to ask. Anyways, if you like your current wheels, just buy spacers. Spacers will push out the wheels towards the fenders. Otherwise, if you want new wheels, most aftermarket guys will supply you with a more aggressive offset, or you can get custom offsets too.
Exactamundo to the above... and an additional benefit of some of the higher end wheel builders is they can also adjust wheel specs to account for your suspension mods if any
Spacer Option - bout $300ish
Wheel Option - starts at $3000ish for forged, maybe $2500 for FF wheels
I just completed a wheel upgrade; I'll walk you through the process and I think it should answer your question.
I think the challenge is that offset and fit can vary depending on the width of the rim and depth of the lip.
The short answer is, in my opinion, a custom offset on the new wheel is better than a spacer, unless you have a certain "unique" vision for how "wide" a stance you want (think RWB).
The long answer is:
I have a 2014 C4S, my wheels were the Carrera Classic II's, which I think were made by BBS for Porsche. I believe the your C2S has the same or similar size rims and offset.
With the factory rims, the rears were a little too "tucked" in under the fenders for my taste. See photos below. I chose to go with HRE wheels because they're a great brand.
HRE Specs:
HRE FF04 Front: 9" wide x 20" diameter, 45mm offset, 245/35ZR/20
HRE FFO4 Rear: 11" wide x 20" diameter, 45mm offset, 305/30ZR/20
Note that the tires are the same (In fact I reused my tires because they were brand new Pirellis, running 305s in back)
Differences
The front rims are .5" wider.
Additionally, front offset is 6mm less, meaning the backplate to the midline of the rim is 6mm closer, causing the rim to sit 6mm further out.
The two combine to make the rim stick out about 1/2" more.
Rear offset is 25m less, meaning the backplate to the midline of the rim is 25mm closer, causing the rim to sit 25mm further out.
Another way to think of this is to take your factory offset, for example, 51 front, 70 rear. Assume width stays constant for now.
Here's where it gets tricky. Adding 10mm spacers REDUCES the offset, and makes the rim stick further out.
A 51mm offset rim with 10mm spacers is a functional 41mm offset rim.
A 70mm offset rim with 15mm spacers is a functional 55mm offset rim.
HRE makes rims specifically for our cars (and others) but I used the calculators below to "check" my math:
Its important to ensure that offset, and clearance, are the same or greater than stock to prevent issues. I've had that happen, and it sucks.
I'll wrap this up by saying choose a brand that manufactures wheels for Porsche fitment and you'll be fine. I'd consider BBS, HRE, Forgeline, Champion, Modulare.
Hope this helps. If you have a specific fitment, I'd be happy to share an opinion.
Fronts, Above
Rears, Above
-----
The photos below show a subtle difference.
Some photos for comparison: HRE OEM - note how rears are slightly "tucked"
Last edited by SFOJAM; 08-10-2019 at 01:30 AM.
Reason: Update. Additional clarity.
Before spacers After spacers Aftermarket with offset Aftermarket with offset
I had put spacer on my 14 Carrera S cab, then decided to get aftermarket wheels and had the offset set up so I didn’t need spacers, like other people said, if you like your original wheels, use spacers, if you go aftermarket have the offset adjusted. I’ll post pictures (if I can lol)
Last edited by Lambomike58; 08-10-2019 at 10:27 AM.
Reason: More info
I used 15mm rear and 8mm front spacers, FYI I’m selling the spacers only used them for less than 200 miles and they come with the extended lug bolts. They are from ECS tuning
Just be aware that as you set the wheels out towards the fender, you will increase the "sandblast" effect on your lower painted panels in the rear (and front if you push those out as well). What most people want is a lowered effect more-so than set out.