DPR Mirror Options for Caterham Sports Cars

  • Eccles mounts to reduce vibration when fixed to doors
  • Pillar mounts to fit to the windscreen stanchions
  • Conversion kit to use the "Spa Black Nut" with the "Two-Hole" base
  •  Mounts to fit to a race roll cage 

1. Standard Door Mounts

  • Pros: Allow the door to open fully (180 degrees), significantly improving access and egress. This is beneficial for daily use.

  • Cons: Highly prone to vibration because the door itself is a flexible, removable panel, often leading to a blurred image at high RPM or speed.

  • Best For: Road use where ease of getting in and out is essential.

1.b. Eccles Style Mounts

Eccles Style Mounts are the optimal solution for eliminating the vibration issue associated with door mounting while retaining the door's full range of motion.

  • Benefit: These rigid brackets minimise vibration.

  • Reason: The mount replaces one of the door's standard hinges. This moves the mirror's anchor point from the flexible door skin to a solid, structural connection to the body tub, which drastically reduces shake and wobble, providing a stable platform for the mirror head.

  • Specifics: DPR supplied Eccles mounts are made of billet aluminium and have the Spa black nut fixing integrated into the design. Furthermore, your purchase includes a donation of £2.50 to the Caterham & Lotus Club where the design originated.

  • Purchase Links: Available from DPR Motorsport (Eccles Mounts).

2. Windscreen Stanchion Mounts

  • Pros: Provide the most stable, vibration-free image because the stanchion is rigidly fixed to the chassis. Excellent for maintaining clear vision at speed.

  • Cons: The mirror position  limits how far the door can open, that can make entry and exit difficult for occupants. Additionally, when the full side-screens are in place, the mirror on the left-hand (passenger) side can have a compromised view.

  • Best For: Road use where image clarity and stability is the highest priority.

  • Purchase Links: DPR Motorsport (Pillar Mounts).

3. Aero Screen / Scuttle Mounts

  • Pros: Offer the lowest drag and a minimalist, race-inspired aesthetic.

  • Cons: Not optimal for road use..

  • Best For: Track days or owners who prioritize aerodynamics thorough eliminating the standard windscreen rather than practicalities.  Fitting a DPR black nut conversion kit enables easier and more reliable mirror adjustment

  • 4. Roll Cage Mounts (Race Cars Only)

    • Pros: Provide ultimate stability and the lowest drag from the smallest possible mirror heads.

    • Cons: Requires a full safety cage.

    • Best For: Dedicated race cars and competition.

    • Purchase Links: DPR Motorsport (Race Parts/Mirror Mounts).

    II. Aftermarket Mirror Units

    After-market mirrors with specific features are necessary to maximize the benefits of any mount.

    • Convex Glass: This is the most important upgrade. Using convex (curved) glass  provides a much wider field of view than standard flat mirrors, compensating for the small size of the unit.

    • Lightweight Housing: These smaller mirrors have less  surface area  which directly reduces vibration and aerodynamic drag.  Both the standard Spa FIA mirror (113 mm x  52 mm) and the larger Spa GT mirror (148 mm x 68 mm) are available from DPR Motorsport. Most customers are satisfied with both the look and performance of the smaller Spa FIA mirror, but the larger-sized GT mirror may suit those who want to maximise viewing area and are less concerned over the look/air resistance.

    • Purchase Links: DPR Motorsport (Mirrors and Accessories).

    III. SPA Black Nut Fixing vs. Standard Base

    The SPA Formula mirror is the most popular choice, but its standard two-hole base often uses an internal screw (grub screw) to lock the mirror head's position. The "black nut" fixing solves the resulting usability issues.

    • Standard Spa Two-Hole Base Issue: To adjust and secure the mirror head, the internal locking bolt must be accessed from underneath or behind the mounting base, making on-the-fly adjustment frustrating.

    • Black Nut Benefit: The "black nut" (a conical adjusting nut) is an external part of the mirror's mounting stem. It allows the mirror head to be adjusted and locked externally without disassembling the mirror or reaching through the bodywork.

    • Conversion Kit: DPR offers a conversion kit that allows the superior SPA Black Nut fixing to be used in conjunction with the standard two-hole base mounting, providing ease of adjustment without needing a completely different mounting system.

    • Purchase Links: DPR Motorsport (Black Nut Conversion Kit).

    IV. Ideal Road Compromise

    The best all-around solution for a road-going Caterham is an Eccles Style Mount combined with a high-quality, lightweight Convex Mirror (often with the Black Nut fixing). This setup successfully offers the best balance of full door access and reduced mirror vibration. For those who want the option to run with and without doors, fitting the DPR pillar mounts allows mirrors to be easily switched between the two solutions.