I hate to ask this question (flame suit on)
#1
Burning Brakes
Thread Starter
Join Date: Feb 2005
Location: Austin, TX
Posts: 885
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I know it's been beaten to death and I did search, but could not find what I needed.
Here's the question:
I have an 87 951, I need to know what offset wheel to buy if I'm going to be using a 31mm thick wheel adapter, also what would be a good width if the wheels are 18"?
please help me out here guys. Thanks!
Here's the question:
I have an 87 951, I need to know what offset wheel to buy if I'm going to be using a 31mm thick wheel adapter, also what would be a good width if the wheels are 18"?
please help me out here guys. Thanks!
#2
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Search "wheel offsets" and you will get 20 pages of discussion. Offsets for an '86 are unique,
where '87-'89 are the same.
Following are notes from various posts that were of interest to me. Perhaps you will find what you need.
951 wheel fitment 5 x 130
Front
18x8.5 ET50 Yes
17x10.5" (11.25" overall) 35mm offset
Here's the catch, the TurboS uses some of the most deeply inset wheels of any Porsche, 65mm offset in front and 60mm offset in the rear. The 996 uses 55mm offsets front & rear, which means if you have same-width wheels as stock 7" front and 9" rear, then they'll stick out about 10mm more than stock. Even more if they're wider than stock.
So the trick is whatever wheels you get, you need to keep the offsets at stock amounts, or even add more offset to push the wheels inwards. That will give you space to run wider wheels and tyres.
__________________
The 993 wide body hollow spokes will fit in the front, they're a 18x8 ET52. The narrow body fronts are 18x7.5.
88' 951 S. The fronts are 18X8s with 52mm offset on 225/45/18s.
This might help you, my offset is ET50 front and ET65 rear. In the rear I have rolled my fenders (1987). I think I read your rear offset is ET54. I have over 10mm clearance to the outside. The 11mm difference between your wheels and mine divided in half is 5.5mm. Based on this I would say you could stick a 285 in there no problem and a 295 would probably fit as well. Matt H could confirm this I would think.
19” wheel On the front you need to reduce offset to 60mm above a 9" wide rim. So for 9.5-11" rims, you want 60mm offset in front.
Rear
18x10 with ET50 maybe
17x11.5" (12.25" overall) 35mm offset
factory '04 996TT 295/18" with rolled rear fender lips (S and '89+ cars already rolled).
10" 993 twists w/295 mm wide Dunlop SSR
narrow body hollow spoke wheels. The offset is 65mm vs the wide body 40mm.
Get the 993 hollow spoke narrow body wheels in the back, they're a 18x10, ET65.
88' 951 S. Rears are 18X11s with 62mm offset on 295/30/18s
255/35 and 285/30 best combo?
I ( and several other people) run the 996 17" twist ("boxster twist") wheels. They are 17x7/17x9 and have 55 mm offset. They fit without rubbing my rolled fenders using a stock alignment. The reduced offset pushes the wheel out so that they fill the fenders a bit more than the stock Club Sport wheels; more attractive. They might rub if the fenders weren't rolled, though.
For USA Spec 1988 951 S and 1989 951
If you want stock Porsche 17 inch wheels you can use these C2 Turbo style without any modifications to the car...
front 8J x 17 AH ET 52mm 965.362.126.01 or 05 from 965 (964 C2 Turbo model) also on RS America
tire 245 / 40 17"
rear 9J x 17 AH ET 55 mm 965.362.128.00 from 965, 928 GT models, and was an option on 968
tire 255 / 40 17"
Safety wise, Porsche AG said for 17" wheels on these cars the limits are:
front 8 x 17 offset 52mm
rear 9 x 17 offset 55mm
Jim Pasha's recommended maximums:
front 8.5 x 17 offset 56mm
rear 10 x 17 offset 60mm
my Fikse's are 17x8.5" ET 50 front and 17x10" ET 56 rear - FIT PERFECT
my BBS Mg's are 17x8" ET 50 and 17x10" ET 47 rear - they fit just as well
But you can use wheels with more offset, i.e. 10" wide and ET 65 in the rear without problems too. They just won't come right to the fender lips like mine do.
Race rules: F: 17/18x8" 55-65mm offset should work R: 17/18x10" 50-60mm offset
I recommend going to the 18" wheels because you have more tire options in the proper diameter; all the wide 17" tires are too tall. So with 18" wheels, you can use 255/35-18 and 285/30-18 tires.
Here's the unofficial word about our front wheels in club racing. Apparently a bunch of 951S club racers measured their front wheels at 7 3/8" and successfully convinced Lance Weeks that the wheel is in fact 7.5". So, 'everyone' running stock 951Ss uses 8.5" fronts.
order wPaul at Radial Tire new Fikse's (8.5 & 10x17 FM-5s). Forgelines w/Wheel Source in Dayton, OH They owners run 2 stock-class 951Ss, so they can set you up with the right offsets (they'll also recommend 18", which cost significantly more).
where '87-'89 are the same.
Following are notes from various posts that were of interest to me. Perhaps you will find what you need.
951 wheel fitment 5 x 130
Front
18x8.5 ET50 Yes
17x10.5" (11.25" overall) 35mm offset
Here's the catch, the TurboS uses some of the most deeply inset wheels of any Porsche, 65mm offset in front and 60mm offset in the rear. The 996 uses 55mm offsets front & rear, which means if you have same-width wheels as stock 7" front and 9" rear, then they'll stick out about 10mm more than stock. Even more if they're wider than stock.
So the trick is whatever wheels you get, you need to keep the offsets at stock amounts, or even add more offset to push the wheels inwards. That will give you space to run wider wheels and tyres.
__________________
The 993 wide body hollow spokes will fit in the front, they're a 18x8 ET52. The narrow body fronts are 18x7.5.
88' 951 S. The fronts are 18X8s with 52mm offset on 225/45/18s.
This might help you, my offset is ET50 front and ET65 rear. In the rear I have rolled my fenders (1987). I think I read your rear offset is ET54. I have over 10mm clearance to the outside. The 11mm difference between your wheels and mine divided in half is 5.5mm. Based on this I would say you could stick a 285 in there no problem and a 295 would probably fit as well. Matt H could confirm this I would think.
19” wheel On the front you need to reduce offset to 60mm above a 9" wide rim. So for 9.5-11" rims, you want 60mm offset in front.
Rear
18x10 with ET50 maybe
17x11.5" (12.25" overall) 35mm offset
factory '04 996TT 295/18" with rolled rear fender lips (S and '89+ cars already rolled).
10" 993 twists w/295 mm wide Dunlop SSR
narrow body hollow spoke wheels. The offset is 65mm vs the wide body 40mm.
Get the 993 hollow spoke narrow body wheels in the back, they're a 18x10, ET65.
88' 951 S. Rears are 18X11s with 62mm offset on 295/30/18s
255/35 and 285/30 best combo?
I ( and several other people) run the 996 17" twist ("boxster twist") wheels. They are 17x7/17x9 and have 55 mm offset. They fit without rubbing my rolled fenders using a stock alignment. The reduced offset pushes the wheel out so that they fill the fenders a bit more than the stock Club Sport wheels; more attractive. They might rub if the fenders weren't rolled, though.
For USA Spec 1988 951 S and 1989 951
If you want stock Porsche 17 inch wheels you can use these C2 Turbo style without any modifications to the car...
front 8J x 17 AH ET 52mm 965.362.126.01 or 05 from 965 (964 C2 Turbo model) also on RS America
tire 245 / 40 17"
rear 9J x 17 AH ET 55 mm 965.362.128.00 from 965, 928 GT models, and was an option on 968
tire 255 / 40 17"
Safety wise, Porsche AG said for 17" wheels on these cars the limits are:
front 8 x 17 offset 52mm
rear 9 x 17 offset 55mm
Jim Pasha's recommended maximums:
front 8.5 x 17 offset 56mm
rear 10 x 17 offset 60mm
my Fikse's are 17x8.5" ET 50 front and 17x10" ET 56 rear - FIT PERFECT
my BBS Mg's are 17x8" ET 50 and 17x10" ET 47 rear - they fit just as well
But you can use wheels with more offset, i.e. 10" wide and ET 65 in the rear without problems too. They just won't come right to the fender lips like mine do.
Race rules: F: 17/18x8" 55-65mm offset should work R: 17/18x10" 50-60mm offset
I recommend going to the 18" wheels because you have more tire options in the proper diameter; all the wide 17" tires are too tall. So with 18" wheels, you can use 255/35-18 and 285/30-18 tires.
Here's the unofficial word about our front wheels in club racing. Apparently a bunch of 951S club racers measured their front wheels at 7 3/8" and successfully convinced Lance Weeks that the wheel is in fact 7.5". So, 'everyone' running stock 951Ss uses 8.5" fronts.
order wPaul at Radial Tire new Fikse's (8.5 & 10x17 FM-5s). Forgelines w/Wheel Source in Dayton, OH They owners run 2 stock-class 951Ss, so they can set you up with the right offsets (they'll also recommend 18", which cost significantly more).
#3
Three Wheelin'
Join Date: Feb 2007
Location: Norway
Posts: 1,324
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
love your post edc, finally lots of good info in a thread.
I might add the 86 takes the 996 18x11 ET63wheel, with a 31-34mm spacer depending on camber iirc, need some gentle mods to some places of fender edge to fit at full suspension travel
I'm converting to 87+ spec for my car, and need to know what spacers to run then, can anyone post what ET they run then?
I see et 62 is suggester, meaning I only need to space aprox 3mm.
I might add the 86 takes the 996 18x11 ET63wheel, with a 31-34mm spacer depending on camber iirc, need some gentle mods to some places of fender edge to fit at full suspension travel
I'm converting to 87+ spec for my car, and need to know what spacers to run then, can anyone post what ET they run then?
I see et 62 is suggester, meaning I only need to space aprox 3mm.
#4
Burning Brakes
Thread Starter
Join Date: Feb 2005
Location: Austin, TX
Posts: 885
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Thanks for the reply EdC, I still didn't find what I need to know though. Sorry guys I have Dyscalculia and its really hard for me to grasp this concept so if anybody can tell me what width range and what offset range I need, it would be greatly appreciated.
#5
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
the 996 wheel in 11" wide is 47-45mm offset- IIRC you can only get the 10" in the 65mm rear offset- but there may be an odd car that these came on w/ the 11" 65mm offset. Why the 31mm spacer?