Porsche Deep Dish Wheels: How We Built a 4.26" Rear Lip with Flush Fitment on a 911

For Porsche owners, a true deep dish setup is about more than choosing a lower offset or pushing the wheels farther toward the fenders.

Wheel width, offset, brake clearance, tire position, center geometry, suspension setup and the desired stance all affect how much visible lip can realistically be created.

This Porsche 911 Carrera 4S is a good example of how those factors come together.

The owner already had a premium aftermarket wheel setup when he came to RVRN. His Porsche already had presence, but he wanted to take one element noticeably further:

a deeper visible outer lip, while keeping the overall stance clean and intentional.

Instead of starting with a preset wheel specification, we worked backward from the vehicle and the owner's vision.

The result was a custom RVRN RV-DP04 forged 2-piece setup, with the rear lip increasing from approximately 2.5 inches to 4.26 inches / 108.2 mm — more than a 70% increase in visible lip depth compared with the previous setup.

The completed Porsche was later displayed with RVRN at the PCA-OCR 54th Annual White Glove Concours & All Porsche Car Show in Dana Point, California.

The goal wasn't maximum poke. It was to create as much usable lip depth as the intended fitment and vehicle geometry would reasonably support.

QUICK ANSWER

How Do You Get Deep Dish Wheels with Flush Fitment on a Porsche 911?

A Porsche 911 deep dish setup with a flush stance requires wheel width, offset, brake clearance, tire position and wheel-center geometry to be considered together.

On this specific Carrera 4S, the final RVRN rear specification was 20×11 ET28, with a 4.26-inch / 108.2 mm outer lip, and without the 5mm spacer used on the previous setup.

The key point is simple:

Deep dish isn't created by offset alone. It is the result of the complete wheel and vehicle geometry working together.

FITMENT BASICS

What Does Flush Fitment Mean on a Porsche 911?

Flush fitment generally describes a wheel and tire position that sits close to the outer fender line without excessive poke, while still maintaining the necessary inner clearance for the tire, suspension and brake system.

That means width and offset cannot be considered independently.

A lower positive offset usually moves the wheel farther outward. But once the wheel reaches the intended fender position, continuing to reduce offset can simply create more poke.

The same applies to wheel width. Adding width without understanding where that additional width is being placed can affect both inner clearance and outer tire position.

So instead of asking:

“What's the lowest offset I can run?”

A more useful question is:

“Where do I want the wheel to sit, and how much usable space remains for the lip?”

That distinction matters when designing Porsche deep dish wheels.

At RVRN, each wheel is developed around the specific vehicle, application and final specifications rather than relying on one universal Porsche fitment. RVRN's current custom wheel process also includes engineering drawings for review before production.

Custom Porsche Forged Wheels

THE STARTING POINT

The Starting Point: A Porsche That Was Already Modified

This wasn't a simple stock-wheel replacement.

The Carrera 4S already had aftermarket wheels, and the previous setup used 5mm spacers to achieve its wheel position.

The owner wanted a noticeably deeper rear lip, but the goal was not to achieve that look by simply moving the entire wheel farther outside the body.

The important comparison looked like this:

The rear lip grew from approximately 2.5 inches to 4.26 inches.

That's roughly 1.7 times the previous lip depth, or an increase of more than 70%.

LIP DEPTH & GEOMETRY

From 2.5" to 4.26": Where Did the Extra Lip Depth Come From?

One of the most common misunderstandings about deep dish wheels is that a deeper lip can be created simply by reducing offset.

It isn't that simple.

If offset alone were used to create depth, the entire wheel would continue moving outward until the final result no longer looked flush.

Several elements influence the usable outer lip.

Wheel width determines the total physical space available, while offset determines where that width sits relative to the hub.

Brake clearance affects how the forged center, mounting pad and spoke profile can be positioned.

The center design and 2-piece architecture affect how the available wheel space can be distributed between the center and outer lip.

Finally, tire position and fender alignment determine how much of that geometry is actually usable on the car.

That is why two wheels with the same width and offset can still have noticeably different visual depth.

Deep Dish is not an offset number. It's an engineering result.

OFFSET & SPACERS

Why the Previous 5mm Spacer Matters

The previous rear setup was:

20×11 ET38 + 5mm spacer.

From a wheel-position standpoint, adding a 5mm spacer moves the wheel outward by approximately 5mm, creating an effective position similar to ET33.

The new RVRN rear specification was:

20×11 ET28

But the significant increase in lip depth did not come from those few millimeters alone.

The wheel center, barrel relationship and final fitment were reconsidered as part of the custom 2-piece design.

Rather than using an additional component after the wheel was produced to establish the desired position, the new wheel specification incorporated the intended position directly into the build.

The stance was designed into the wheel, rather than added afterward.

ENGINEERING & APPROVAL

Two Drawing Revisions Before Production

This fitment was not finalized from the first engineering drawing.

Before machining began, the RVRN engineering team and the owner went through two drawing revisions.

Those revisions were used to refine the relationship between the wheel position, visible lip depth and the overall proportions of the Porsche.

The purpose wasn't simply to approve a set of dimensions on paper.

It was to make sure the owner was comfortable with the direction of the build before the wheels entered production.

With each revision, the fitment moved closer to the desired balance between deep dish presence and a clean Porsche stance.

Only after the final drawing was reviewed and approved did production move forward.

The finished stance wasn't guessed. It was reviewed, revised and developed together with the owner before machining began.

This approval-based process also reflects RVRN's current production workflow: engineering drawings are prepared for customer review before the wheel moves into production.

PORSCHE DEEP DISH GUIDE

How Deep Can Porsche 911 Wheels Be?

There is no single maximum lip depth that applies to every Porsche 911.

The available depth changes with the 911 generation and model, wheel width, offset, brake package, tire size, suspension setup, center design and desired fender position.

On this particular Carrera 4S, RVRN achieved a 4.26-inch / 108.2 mm rear lip.

That number should be understood as a result of this specific build — not as a universal Porsche 911 specification.

Another 911 may reasonably support more or less visible lip depending on its geometry and the owner's fitment goals.

This is why vehicle-specific engineering matters more than copying a specification from another Porsche.

WHEEL DESIGN

Deep Dish vs. Concave Wheels: What's the Difference?

Deep dish and concave are both ways of creating visual depth, but they describe different parts of the wheel.

Deep dish refers primarily to the visible outer lip between the wheel center and the outer rim edge.

Concave describes how aggressively the spokes or wheel face sweep inward toward the hub.

A wheel can incorporate elements of both, but vehicle geometry and brake clearance determine how far each direction can reasonably be taken.

For this Carrera 4S, the priority was clear:

Create a significantly more visible outer lip while maintaining the intended stance.

That made a forged 2-piece construction particularly useful. RVRN's current 2-piece platform allows the separate forged center and barrel to be configured for different widths, offsets, lip depths and finish combinations.

WHEEL CONSTRUCTION

Why a Forged 2-Piece Wheel Made Sense for This Build

This project needed control over more than the spoke design.

The wheel architecture had to support the intended relationship between width, offset, center position, outer lip and finish separation.

A forged 2-piece wheel uses a separate center and barrel, providing more flexibility in those areas than a fixed one-piece specification.

RVRN currently builds its custom 2-piece wheels from forged 6061-T6 aluminum and develops each set around the specific vehicle and application.

Final RVRN Setup

RV-DP04 Porsche 911 Custom Forged 2-Piece Wheels

FINISH & APPEARANCE

Why the Finish Makes the Deep Dish More Visible

Actual lip depth is determined by wheel geometry.

How strongly that depth reads visually is also influenced by finish.

For this build, the wheel used:

Transparent Bronze spokes with a Brushed Barrel and Polished Outer Lip.

The contrast between the bronze center and polished lip creates a clearer visual boundary between the two sections.

As light moves across the polished surface, the outer lip becomes more defined, making its depth easier to read from different angles.

If the entire wheel had been finished in one dark tone, some of that physical depth could appear visually flatter.

That is why finish was not treated as a separate afterthought on this project.

Lip depth is engineering. Perceived lip depth is also design.

OFFSET & FITMENT

Porsche 911 Wheel Offset for Flush Fitment: Is There One Correct Number?

No.

There is no universal Porsche 911 wheel offset for flush fitment.

The correct offset changes with the specific generation, trim, wheel width, tire size, brake package, suspension and desired stance.

For this Carrera 4S project, the final RVRN specifications were:

20×8.5 ET39 front and 20×11 ET28 rear.

Those numbers document this particular project. They should not be copied automatically to another Porsche 911.

The same principle applies across other Porsche models including the Cayman, Boxster, Panamera, Taycan, Macan and Cayenne.

RVRN CUSTOM PROCESS

How RVRN Approaches Porsche Fitment Before Production

The final wheel should be developed around the vehicle rather than asking the vehicle to work around a preset wheel.

RVRN's current workflow includes vehicle-specific specifications, brake-clearance consideration and engineering drawings for customer review before production. The company's 2-piece product pages also position lip depth, width and offset as customizable elements of the wheel architecture.

For this Porsche, that process became especially important because the goal wasn't simply replacement wheels.

It was a very specific combination of:

deeper outer lip + intended flush position + no spacer + owner-approved proportions.

The two drawing revisions were part of getting those elements to work together.

PCA-OCR · WHITE GLOVE CONCOURS

Built for the Owner. Shown at PCA.

The finished Carrera 4S wasn't created only for a rendering or studio photos.

RVRN later displayed the Porsche at the PCA-OCR 54th Annual White Glove Concours & All Porsche Car Show in Dana Point, California.

That gave Porsche owners the opportunity to see details that numbers alone don't fully communicate:

the relationship between the wheel and fender, the visible depth of the rear lip, the way the polished surface reacts to natural light, and the overall proportions of the wheel on the 911.

Fitment numbers describe where a wheel sits. The finished car shows how those numbers work together visually.

COMMON QUESTIONS

Porsche Deep Dish Wheels & Flush Fitment FAQ