FQRANBO Firewall Pass-Through for Holley Terminator X Max — Black Anodized Aluminium Bulkhead with 1-1/8" & 3/4" Holes

FQRANBO's Firewall Pass Through is a two-piece anodized aluminum bulkhead designed to replace the stock grommet and route your Holley Terminator X Max engine harness cleanly through the firewall.

When installing performance engine management systems like the Holley Terminator X Max, protecting and organizing the wiring that crosses the firewall is critical for longevity and serviceability. This pass-through replaces cramped rubber grommets with a robust aluminum bracket that reduces chafing, resists heat and corrosion, and creates a tidy, repeatable bulkhead entry for your main engine harness.

How does this pass-through protect my Holley Terminator X Max wiring?

The unit uses an arc-shaped harness aperture and a two-piece clamshell design to cradle wiring without sharp edges. Anodized aluminum construction adds thermal and corrosion resistance compared with softer grommet materials. Together these features lower abrasion and strain on the harness at the firewall penetration.

• Arc-shaped hole reduces cable friction and wear
• Two-piece bracket clamps the harness gently yet securely
• Anodized aluminum resists heat, rust and corrosion

What size openings and fit dimensions should I expect?

The pass-through provides two factory-specified openings to accommodate the main harness and auxiliary lines: a 1 1/8" hole and a 3/4" hole. Its overall footprint is compact for common firewall locations while offering enough clearance to route the Holley Terminator X Max connector and its bundled wires comfortably.

• Main hole diameter: 1 1/8" (for primary harness)
• Secondary hole diameter: 3/4" (for smaller runs or sensor leads)
• Outside dimensions: 3.78" × 2 1/8" for a low-profile installation

How is the pass-through installed and secured?

Installation follows a straightforward sequence: mount the base plate to the firewall first, route the harness, then fasten the top plate with the included middle bolts. Finally, secure the assembly to the vehicle using the four mounting bolts for a solid, repeatable attachment that makes future service easier.

• Two-piece design uses middle bolts to join upper and lower brackets
• Base plate mounts first, harness laid in, then panels reassembled
• Four outer bolts secure the assembly to the firewall

Why choose aluminum and what maintenance is needed?

Aluminum provides a strong, lightweight barrier that tolerates engine-bay heat and resists rust better than many steels. The surface is anodized and precision-polished to limit corrosion and help the pass-through hold up under regular use. Maintenance is minimal: inspect for secure fasteners and ensure wiring remains seated in the arc-shaped aperture.

• Anodized finish improves corrosion resistance and appearance
• Polished surfaces reduce friction on wires over time
• Periodic visual checks recommended after track or long drives

Who is this for: This FQRANBO Firewall Pass Through is aimed at vehicle owners, tuners and installers fitting a Holley Terminator X Max who want a durable, neat firewall entry that eliminates the factory grommet. It’s ideal for performance builds, restorations, or anyone seeking a safer, more serviceable wiring routing solution that reduces chafing and enhances engine-bay organization.