BMW N55 Oil Pan/Sump Baffle & Rod/Big End Bearing Upgrade – MMR Oil Control/Windage Plate + ACL Race Conrod Bearings + ARP Rod Bolts | F20

Ultimate oil control and bottom-end protection for BMW F-series N55

Serious driving exposes a known lubrication weakness on the turbocharged BMW straight-six. Hard deceleration and long corners can cause oil to move away from the pick up, risking pressure drop and bearing distress. This kit solves the problem while upgrading critical components for reliability on fast road and circuit use.

What you get

• MMR N55 oil pan baffle plate with directional flaps for surge control
• ACL Race con rod bearings for high-load durability
• ARP rod bolts for superior clamping security at sustained rpm

Why this package works

MMR oil control baffle keeps lubricant concentrated around the pick up during aggressive braking and cornering. The anodised T6061 aluminium plate uses seven one-way trap doors and tailored baffling to stabilise pressure under G. It bolts in place with the sump removed, no welding required, and has been proven over extensive road and circuit mileage. Expect consistent lubrication, reduced aeration and peace of mind when you lean on the car.

ACL Race bearings are a go-to choice for performance N55 builds, offering dependable film strength and wear resistance under elevated loads and temperatures. Perfect when pairing with hybrids, higher boost and extended track sessions.

ARP conrod bolts deliver trusted clamping force for the big ends, improving bottom-end integrity during high rpm shifts and sustained abuse. A sensible upgrade any time rods are removed or when prepping for spirited use.

Ideal for

• Fast road, track days, time attack, drag and Nürburgring trips
• Tuned cars running Stage 1, Stage 2 or hybrid turbo setups
• Preventative maintenance during sump-off service work

Compatible models

BMW F2x and F3x with the N55 engine, including:

• 1 Series: F20 F21 M135i
• 2 Series: F22 M235i
• 3 Series: F30 F31 335i
• 4 Series: F32 F36 435i

Why buy from MJ Modifications

We have installed this setup on multiple customer cars and our own builds. Feedback has been outstanding, with customers reporting rock-solid oil pressure on circuit and greater confidence when braking deep and carrying speed through long bends. It is one of the smartest preventative upgrades you can do on an F-series N55.

Fitting service

Professional installation available at MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a fitting quote and availability.

Key search terms

BMW N55 oil pan baffle, sump baffle kit, oil surge prevention, oil pressure stabilisation, BMW M135i oil control, M235i track preparation, 335i reliability upgrade, 435i performance parts, ACL Race bearings N55, ARP conrod bolts N55, fast road and track.