After so many shops couldn’t get it right, we tore the whole drivetrain apart and started over. The engine came out for a full reseal from the pan to the valve cover, and the chassis, brakes, suspension, and driveline were rebuilt around it. Now it makes regular trips to NYC.
A turbo exhaust manifold a few inches below a plastic valve cover is a problem waiting to happen. On this CSL it had already happened: the old valve cover had gotten so hot it was dripping plastic onto the exhaust manifold.
The fix came out of BMW’s own parts bin. The S54 exhaust manifold gasket has a heat shield built into it, made to protect that engine’s plastic valve cover. It does not drop straight onto an S52 with a turbo manifold, so we modified it to fit, checked it against the head, and the custom heat shields now sit between the turbo manifold and the new valve cover.
With the engine out, oil was leaking through the layers of the old MLS head gasket, the timing cover was warped, and the head showed signs of lifting, so the head and timing cover were resurfaced flat and it went back together on head studs and cut-ring head gaskets from 5150 Autosport.
The scope of work
- Engine
- Engine out and resealed from the oil pan to the valve cover: head and timing cover machined flat, camshafts and caps polished, ARP head studs and a cut-ring head gasket set from 5150 Autosport, new rear main seal and housing gasket, VANOS cover seal and oil feed line, and every coolant seal and flange from the water pump to the thermostat housing
- Turbo and heat
- Turbo clocked, oil drain shortened in 10AN with a 45° fitting and a welded 10AN oil pan bung, 4AN stainless oil feed, wastegate plumbed in hard line, and exhaust manifold gaskets with built-in heat shields plus Second Skin thermal barrier
- Fuel
- Fuel hoses replaced with 1/2-inch (8AN) aluminum hard line and Fragola fittings, with the engine-bay soft hoses redone to fit
- Brakes
- F30 M Sport caliper conversion with 340 mm Z-coated rotors and Textar pads, and custom 3/16 stainless lines front to rear with 3AN fittings, a junction tee, and a pressure switch adapter, bled with Motul RBF600
- Suspension and steering
- CATuned E34-style front spindle conversion with new hubs, inner and outer tie rods, idler arm, compression rod and control arm bushings, a refinished power steering box, rear trailing arm links on correct hardware, and coilovers preloaded and set at all four corners
- Driveline
- Meyle heavy-duty guibo and new pilot bushing, custom reinforcement mounts for the driveshaft, a chassis-mounted shifter with the tunnel trimmed to fit, and new transmission output and selector shaft seals
- Accessories
- Bosch 140A alternator, power steering pump rebuilt with an inline magnetic filter, metal water pump pulley and belt kit, INA idler pulley, and a new belt tensioner
- Fabrication
- Custom chromoly tow D-rings and support brackets, laser cut and welded on, with self-tapping screws throughout replaced by threaded inserts and proper hardware
- Refinishing
- Front crossmember, pitman arm, compression rods, and strut mounting brackets powdercoated
