BMW M50 S50 S54 Engine Girdle Kit (ARP studs incl) by Diff Lab
Diff Lab's own Australian made engine girdle for M50, S50 and S54 engines. It is a universal fitment and the strongest girdle available. It is made from Australian 350MPa structural steel, and cut to tight tolerances. This girdle fits much more tightly around the main cap bolts versus other engine girdles. It is the only girdle available which can be drilled to suit your engine. It is the only girdle available which features additional pilot holes for fixing directly to the block. Holes for an engine scraper are pilots only, and won’t be drilled for S54 and E34 (front sump) engines, ensuring superior strength.
The main cap straps are triangulated for additional strength. A set of fourteen super-strong 4140 billet steel spacers are included. Available exclusively from Diff Lab and partner workshops. The best girdle available is also the cheapest, at more than a couple of hundred dollars less than an imported item. These are not zinc plated, eliminating the risk of cracked or lifted zinc plating ending up in the engine oil.
Use this engine girdle to prevent main cap 'walking' and to generally strengthen the bottom end. Fixing the girdle to the engine block directly provides the best strength.
To fit: M50, S50, S54 engines. Pilot holes are to be drilled to suit your engine. The girdle requires the main bolts to be changed to M50 ARP head studs (included in kit) which are slightly longer to accommodate the girdle and spacers.
Most engines will require some relieving of the oil pump for clearance.
Included: 1x Engine Girdle, 14X 4140 Steel Spacers, 1x set ARP Studs.
Instructions
For all engines:
When using an engine girdle for racing, fill the engine oil to the "full" line on the dipstick. Add a measured 500ml of additional engine oil. Based on experience, modifying the oil pickup(s) is not required.
For M50 without scraper:
Drill red through girdle and block if additional strength is required. Fix with M6 countersunk machine screws. (optional)
For M50 with scraper:
Drill green to 8mm and install scraper with new 12.9 high tensile bolts and washers.
Drill red through girdle and block if additional strength is required. Fix with M6 countersunk machine screws. (optional)
For S50/S54:
Drill red to 7mm (drill block to 5mm) through girdle and block if additional strength is required. Fix with M6 countersunk machine screws. (optional)
Drill blue to 10mm if block has additional oil drains in these two locations.
Drill green to 7mm (drill block to 5mm), countersink, and install M6 countersunk to affix girdle to block if additional strength is required. (optional)