I have my old pair 20" wheels/tires from my 997tt. Would it be possible to put on the 991tt. I'm sorry I do not know the offsets or other specifics. If so, what am I to look for.

 

The brakes on the 991 TTS are significantly larger, however the 20's should fit.
The offsets should be stamped on the inside of your 997 wheels. The 991 turbo offsets are front ET51 & rear ET56. The Porsche 5 bolt pattern is the same, however you would need different wheels if you have centerlocks on one car & not the other! You could also put on the Porsche 5mm spacer kit which would make them fit if your aftermarket wheel offsets aren't enough clearance.

 

what wheels you trying if its HRE or ADV they will have serial number which we can use to verify all specs and fitment. Now if you do want we trade in old wheel or stock wheels towards a new set built perfectly for your turbo

 

Could not find the offsets inside the wheels. What issues do I need to watch out for:
- brake clearance
- how do I determine if it needs spacers
- what size spacers
- bolt length

Thanks

 

Besides the offset check the inside barrel of the wheel to see if there is a ring that protrudes into the diameter of this barrel. When I was fitting my Turbo S with winter wheels, I found there were some 20" rims with this feature that prevented the brake caliper from sliding safely through the barrel unobstructed. If you have the steel brakes, I believe you should not have his problem as the O.D. of the front caliper is smaller than the front PCCB caliper where my problem occurred. I did not have a problem with this same rim model when installing it on the rear 5-bolt lugs on my TTS.

 

what brand of wheel is it ?

 

Also remember the rear brake discs if Ceramics , have the disc shields which sit behind the disc and adds another 2-3cm ....I had to have these cut down to fit a set of light trackday wheels ...
Sorry poor quality pic of the modified shield

 

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