Ford 2.3 EcoBoost Closed Deck Conversion | Mustang EcoBoost & Focus RS | EPOXY54

Ford 2.3 EcoBoost · Inline 4 · Open-Deck

The 2.3 EcoBoost
Has an Open Deck.
Boost Makes It Matter.

Ford's 2.3L EcoBoost in the Mustang EcoBoost and Focus RS uses an open-deck aluminum block — engineered light, but unsupported where it counts. Add boost, and bore distortion and head gasket failure follow. EPOXY54 closes the deck for $124.99, no machining required.

Order EPOXY54 — $124.99 →
2.3 EcoBoost Kit Details
$124.99
Inline 4 Kit Price
21,000 PSI
Compressive Strength
24 hrs
Cure Time
S550 / C307
Common Chassis
Why the 2.3 EcoBoost Needs This

Open Deck + Forced Induction = A Known Failure Mode.

Ford's 2.3L EcoBoost is a well-designed turbocharged engine — but the open-deck aluminum block has a structural limit that shows up once boost is pushed beyond factory parameters.

Bore Distortion Under Boost

The open water jacket leaves the cylinder walls unsupported at deck level. Under elevated cylinder pressure, the bores flex. This breaks the ring seal, causes blow-by, and degrades power output over time.

Head Gasket Movement

Cylinder wall flex under load means the deck surface isn't static. The head gasket is being asked to seal a surface that moves — and eventually it lifts. This is the most common failure mode on modified 2.3 EcoBoost builds.

The Ceiling on Tuned Builds

Whether it's an OTS tune, E85, or a full bolt-on build, the open deck is the structural limit on the 2.3 EcoBoost. Closing it removes that ceiling before it becomes an engine-down repair.

Track use and sustained boost accelerate the risk: The Mustang EcoBoost and Focus RS communities have documented head gasket failures disproportionately on modified and track-driven examples. The open deck is the common thread — and closing it is the fix builders use before the failure happens.

Cost vs. Outcome

EPOXY54 vs. Closed-Deck Shortblock vs. Sleeves

Three approaches to the 2.3 EcoBoost open-deck problem. The cost range is significant.

Feature EPOXY54 Closed-Deck Shortblock Machined Sleeves
Cost $124.99 $1,500–$4,000+ (before labor) $2,000–$4,000+ installed
Deck-Level Structural Support ✔ 21,000 PSI fill ✔ Machined closed deck ✔ Full bore support
Uses Your Existing Block ✔ ✘ Full replacement ✔
Machining Required ✔ None ✘ Full machined build ✘ Bore & press fit
OEM Cooling Maintained ✔ Passages drilled back ✔ ✔
DIY Friendly ✔ ✘ Full engine rebuild ✘ Machine shop only
Turnaround 24 hrs cure Weeks 2–4 weeks (shop queue)
Installation

The Process on a 2.3 EcoBoost Block

Engine out, head off — applied once during your build. Fits Mustang EcoBoost and Focus RS blocks identically.

1

Prep the Block

Block cleaned and bare with head removed. Fill the water jacket with a water-soluble temporary solute to displace the lower jacket during the pour.

2

Mix & Pour EPOXY54

Pour EPOXY54 into the top ¾" of the water jacket around all four cylinders. Distribute evenly across the full deck surface.

3

Cure 24 Hours

Room temperature cure. At full cure the fill reaches 21,000 PSI compressive strength — no heat, no press required.

4

Drill Coolant Passages

Drill coolant passages back through the cured epoxy per the head gasket layout. Full OEM cooling restored.

5

Flush & Reassemble

Dissolve and flush the temporary solute. Inspect passages and proceed with head gasket installation and engine assembly.

Common Questions

2.3 EcoBoost Builder FAQ

For Mustang EcoBoost and Focus RS builders.

Yes. The Ford 2.3L EcoBoost in the Mustang EcoBoost and Focus RS uses an open-deck aluminum block — the water jacket is open at the deck surface, meaning the cylinder walls are not fully supported at the top of the block. This is a documented characteristic of this engine architecture and is the structural reason head gasket failures occur on modified examples.
At modest tune levels, the open deck is generally not an immediate concern for street driving. EPOXY54 is most relevant when doing a full engine build, running elevated boost, using E85, or tracking the car regularly. If you're pulling the engine for any reason, adding EPOXY54 during the teardown costs one day of cure time and removes the open-deck ceiling before it becomes a head gasket failure.
Yes. Both the 2015+ Mustang EcoBoost and the 2016–2018 Focus RS use the same 2.3L EcoBoost engine block. EPOXY54 is applied to the bare block with the head removed — the chassis it came out of is irrelevant to the process.
This page covers the performance application in the Mustang EcoBoost and Focus RS. The 2.3 EcoBoost appears in other Ford vehicles, but the power targets and boost levels differ significantly. If you have an application outside these two, contact EPOXY54 directly to confirm before ordering.
Yes. EPOXY54 fills the open deck void around the cylinders — it does not interact with internal rotating components. It's fully compatible with forged pistons, rods, and any other bottom-end hardware, and is commonly used alongside forged internals in full builds.

Close the Deck
Before It Closes Itself.

An open-deck 2.3 EcoBoost under boost is a head gasket failure waiting to happen. EPOXY54 fixes the structural problem for $124.99 — during the build, not after the damage.

$124.99
Inline 4 Kit
Order EPOXY54 →

Ships fast · No machining required