Sky High Oversized 4 Gauge OFC Big 3 Upgrade Green/Black Wiring Kit

In this review the Sky High Oversized 4 Gauge OFC Big 3 Upgrade Green/Black Electrical Wiring Kit is evaluated for installers and serious car audio enthusiasts who need a robust power and ground upgrade. The bottom line: this kit is a straightforward, heavy-duty choice for improving charging and grounding paths in systems where efficiency and reliability matter. The reviewer found it particularly useful for vehicles receiving high-output alternators or upgraded amplifiers because it focuses on core wiring improvements rather than extras, making it a practical component in a larger audio or electrical upgrade.

Key Features

• 4 gauge OFC wiring: Provides a thicker conductor for lower resistance and improved current flow compared with factory wiring, which helps large audio systems get cleaner power.
• Big 3 upgrade focus: Targets the three main charging and grounding paths to reduce voltage drop and improve alternator performance under high load.
• Green/black color scheme: Makes routing and identification easier during installation or future troubleshooting.
• Complete kit approach: Bundles the core wiring components needed for a Big 3 upgrade so installers do not need to source multiple separate cables.
• OFC construction: Uses oxygen-free copper conductors to maximize conductivity and reduce corrosion risk at connection points over time.

Who It's For

The kit is best for DIY installers, sound installers, and car audio enthusiasts upgrading amplifiers or installing higher-output alternators who need reliable, thicker power and ground wiring. It suits vehicles where the factory wiring shows voltage drop under load or where improved charging stability is desired.

It is less suited to owners who need a complete audio package with fuses, distribution blocks, or terminals included; buyers needing those extras should plan to purchase matching connectors or fuse blocks separately. Also, those working on very small systems or purely cosmetic builds may find this heavy-gauge kit overkill.

Pros & Cons

Pros

• Thicker 4 gauge OFC conductors reduce resistance compared with stock wiring and help sustain voltage under load.
• Designed specifically for the Big 3 upgrade, which targets the most impactful wiring paths for performance gains.
• Color-coded green and black wiring simplifies installation and future maintenance.
• Sold by a specialist retailer that stocks related high-end car audio components for compatibility.

Cons

• Does not list included terminal types or fuse hardware, so additional connectors may be required for a finished install.

Specifications

Product name	Sky High Oversized 4 Gauge OFC Big 3 Upgrade
Gauge	4 gauge
Conductor type	OFC (oxygen-free copper)
Color	Green and black
Intended use	Big 3 charging and ground upgrade for vehicles
Brand	Sky High Car Audio

Our Verdict

The Sky High 4 Gauge OFC Big 3 wiring kit is a practical, value-minded upgrade for installers improving alternator performance and reducing voltage drop in medium to high demand audio systems. It delivers the core benefit of thicker OFC conductors and clear color coding, but buyers should plan for connectors or fuse hardware if their installation requires them. Overall it is a sensible pick for those prioritizing reliable power and grounding improvements.

Frequently Asked Questions

Does this kit include fuse blocks or terminals?
Answer. The listing focuses on the wiring itself; customers should expect to source terminals or fuse hardware separately unless specified at purchase.

Is the wiring suitable for high-output alternators?
Answer. Yes, 4 gauge OFC conductors are appropriate for improving the Big 3 paths and handling higher currents encountered with upgraded alternators and amplification loads.

Can a novice install this kit?
Answer. A knowledgeable DIYer can install it, but basic crimping, terminal selection, and safe battery/disconnect procedures are required; professional installation is recommended if unsure.