| Porsche Technical Discussions Porsche related technical discussions and questions go here. |
![]() |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
|
Hello everyone,
My name is Derrick Jr., and I am a new member from California looking for some guidance. I need help understanding wheel fitment specifications. Previously, I have only worked with the ET63 offset typically found on OEM Porsche wheels. Now, I need clarification on how a backspacing measurement, specifically 7 5/8 inches, relates to those figures. More specifically, my vehicle can accommodate an 11-inch wide rim with an offset (ET) in the range of 60mm to 63mm. I am trying to determine if an 11-inch rim with a backspacing of 7 5/8 inches falls within that acceptable range. Any insights you could provide would be greatly appreciated. Thanks in advance. Derrick Jr. |
|
#2
|
||||
|
||||
|
Quote:
__________________
David I hope to arrive to my death, late, in love, and a little drunk! Just because I don't care doesn't mean I don't understand... Homer Simpson "That's what's keeping me out of F1.... Too much mental maturity...." N0tt0n Some cause happiness wherever they go; others whenever they go. CHAOS, PANIC, AND DISORDER my work here is done... Live without pretending, Love without depending, Listen without defending, Speak without offending |
|
#3
|
||||
|
||||
|
That ET is about 2-1/2 inches. so for an 11 inch rim that would be an 8-1/2 inch backspacing.
__________________
David D. '87 Targa - 2024 was the year, beeches... |
|
#4
|
||||
|
||||
|
FWIW, the offset is how far off the centerline the HUB of the wheel is, while the backspacing is the space behind the SPOKES. The two measurements are separate and not directly relatable, as the spoke shape varies.
ed
__________________
ed 2016 GT4 2005 Lotus Elise 1994 RX-7 R2 |
|
#5
|
||||
|
||||
|
Quote:
__________________
David I hope to arrive to my death, late, in love, and a little drunk! Just because I don't care doesn't mean I don't understand... Homer Simpson "That's what's keeping me out of F1.... Too much mental maturity...." N0tt0n Some cause happiness wherever they go; others whenever they go. CHAOS, PANIC, AND DISORDER my work here is done... Live without pretending, Love without depending, Listen without defending, Speak without offending |
|
#6
|
||||
|
||||
|
Try this. You can enter wheel and tire size and see ET (off-set) etc.
https://www.wheel-size.com/calc/ Cheers Engelbert
__________________
LED Lights for Classic Porsches 2015 911 Turbo 2012 Boxster S 2006 Cayenne S 1982 911 SC 1978 1303 Kaefer Cabrio 1971 911 3.6 |
![]() |
|
|