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YOUR RESEARCHI don't understand 'OFFSETS' (My Secret Shame.....)
Leading reported evidence
Set limits
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1
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Read evidence and context
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On the site I use, you can set the limits for spring and fender clearance in mm which can be very helpful.
I don't understand 'OFFSETS' (My Secret Shame.....)
Frequently discussed work
Check ie against oem specs
No successful repair reported for this finding.
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Suggestion
Those sites are good for a safe check ie against OEM specs but if your looking to push the boundaries of what’s possible there are other factors that they don’t take account of eg OEM are generally “safe” and you can push the outer limits 5-20mm and still be safely within the arches without rubbing (hence why people fit spacers to OEM specs) and you can also play with the inners but have to consider if they will catch either the suspension or caliper.
I don't understand 'OFFSETS' (My Secret Shame.....)
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Leading evidence: 'Set limits' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check ie against oem specs' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion
Those sites are good for a safe check ie against OEM specs but if your looking to push the boundaries of what’s possible there are other factors that they don’t take account of eg OEM are generally “safe” and you can push the outer limits 5-20mm and still be safely within the arches without rubbing (hence why people fit spacers to OEM specs) and you can also play with the inners but have to consider if they will catch either the suspension or caliper.
I don't understand 'OFFSETS' (My Secret Shame.....)
Tighten torque and so
Suggestion or failed attempt
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Unsuccessful attempts
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Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Suggestion
is also handy for checking all sorts of information such as the correct wheel bolt size, tightening torque and so on, once you've figured out offset which is basically how much a wheel sticks out.
I don't understand 'OFFSETS' (My Secret Shame.....)
Frequently discussed actions (3)
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Check ie against oem specs
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Those sites are good for a safe check ie against OEM specs but if your looking to push the boundaries of what’s possible there are other factors that they don’t take account of eg OEM are generally “safe” and you can push the outer limits 5-20mm and still be safely within the arches without rubbing (hence why people fit spacers to OEM specs) and you can also play with the inners but have to consider if they will catch either the suspension or caliper.
I don't understand 'OFFSETS' (My Secret Shame.....)
Tighten torque and so
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
is also handy for checking all sorts of information such as the correct wheel bolt size, tightening torque and so on, once you've figured out offset which is basically how much a wheel sticks out.
I don't understand 'OFFSETS' (My Secret Shame.....)
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10 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
911uk: 1 discussions
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All - as the title suggests - I don't properly understand wheel measurements and offsets. I'm 50. I feel I can admit it amongst this small, closed circle of trusted friends.
I'm interested in a new (pre-owned) set of wheels for my 996 C4S. The wheel stats are:
Fronts are 19 x 8.5 width (same as standard turbo wheels)
ET +50
Rears are 19 x 12 (standard turbo is 11 width I think)
ET 51
Question is this: Will they fit on my widebody car, or will I need spacers? car has the standard 18inch hollows ATM.
Also - am I likely to encounter a rubbing of parts that could be either unwelcome or dangerous?
Thanks all.
Offset is measured from the centreline of the wheel (between the tyre beads) and the mounting face. Positive is towards the face of the wheel.
I have found this fitment guide to be very helpful:
https://apexwheels.com/fitment-guid...96-c4s-and-turbo-wheel-and-tire-fitment-guide
I would expect these to fit your turbo fine with out spacers. be far too wire for my narrow body. I have et40 x 10 which only just fit. your are 2 inch wider but only sit in 11mm more.
https://www.wheel-size.com
is also handy for checking all sorts of information such as the correct wheel bolt size, tightening torque and so on, once you've figured out offset which is basically how much a wheel sticks out.
Those sites are good for a safe check ie against OEM specs but if your looking to push the boundaries of what’s possible there are other factors that they don’t take account of eg OEM are generally “safe” and you can push the outer limits 5-20mm and still be safely within the arches without rubbing (hence why people fit spacers to OEM specs) and you can also play with the inners but have to consider if they will catch either the suspension or caliper. Once you get the hang of it you can have some fun. some cars have much more scope than other ie those with a relatively narrow axle / wide arch combo but generally Porsches do not fit into that catagory unless you fit arch extensions.
Ps I guess my answer is over the top for your question but its to point out the quest for this knowledge can have you running down rabbit holes lol
On the site I use, you can set the limits for spring and fender clearance in mm which can be very helpful. Calipers can also be tricky.
That however doesn't take into account the different size and shape of tyres, as not all tyres are the same, even if they are ostensibly all the same size. For example, a winter tyre has a different profile to a semi slick which is very square; and a road tyre like an MPS4S has a significant 'shoulder' for kerb protection; all this can affect the fitment and clearance.
And I haven't mentioned ride height and alignment yet.
This is a source reference. Confirm exact model applicability in the original material.
