528e Complete Engines

528e Complete Engines & Cylinder Heads

M20 Engines: A Brief History

The M20 engine group was introduced in the late 70's in 2.0L and 2.3L sizes in the European model BMW 320/6 and 323. A later 520 sedan combined the fuel economy of the small six with the convenience of a 4 door sedan.

With consumer demand for more power, engine size was increased to 2.5 L, and in the new E30 chassis, electronic fuel injection powered the 323 and 325 versions. In the shadow of another fuel shortage BMW developed the ingenious 2.7 L eta engine which came to the U.S. in the 1982 528e and '84 325e. The engine was designed for minimum friction loss, highest possible fuel efficiency and maximum low rpm torque. In comparison, the 2.7L eta produces 170 lb/ft of torque at 3250 rpm, whereas the 2.8L 528i (M30 engine) produces the same amount of torque but at 4500 rpm.

See related information under Rebuilding: Engines and Turbos

Korman Autoworks offers 4 basic rebuilding configurations:

Stock
Stage 1 and 2 Competition (not emissions legal due to inclusion of cams)
Stage 1 Clean Air Engine-Emissions legal-50 States
Korman 2.7 Stroker Engines-(emissions legal variants available)
Korman Competition Engines(not emissions legal due to inclusion of cams)

Korman Stock Rebuilds

2 year/24,000 mile warranty

Our stock rebuilds are assembled to BMW specifications by our experienced and dedicated technicians rather than off a mass production assembly line. Korman engines are assembled with meticulous craftsmanship, precise machining, and detailed blueprinting. All of our boring is done with a torque plate for exceptional bore roundness and long engine life. These hand built engines are available at prices comparable to a factory reman units which offer only 12 month/12,000 mile warranties.

M20 528e 82>88 P/N 11036100

Korman Stage 1 Competition Engines

2 year/24,000 mile warranty

Korman Stage 1 Competition Engine-M20

Our Stage 1 rebuild will provide a moderate increase in power through the use of our proven performance techniques. Special valve and valve seat work, increased compression, Korman-Stahl Headers and Stage 1 cylinder head porting will net a gain of 12-25 HP depending on model. Performance computer chip suggested, not required.

M20 eta P/N 11036410

Korman Stage 2 Competition Engine-M20

Our Stage 2 engines are designed for maximum performance without adversely affecting engine life or driveability. All Stage 2 Engines receive our flow testing porting and polishing, proven 3 angle valve seat work, back cut intake valves, dual valve springs, titanium retainers, Korman Rocker Arms, Korman-Stahl headers, and a Schrick 272 Camshaft (upgradable to a Schrick 288 on some models). M20 "i" engines receive our aluminum flywheel, while M20 "eta" engines receive our exchange lightweight flywheel. Korman performance computer chip suggested but not included.

M20 eta P/N 11036370

Korman High Performance Clean Air Engines

2 year/24,000 mile warranty

Stage 1 High Performance Clean Air Engine-M20

In our Stage 1 Clean Air Engines we apply our high performance techniques to extract maximum power from stock parts while making no changes that affect Federal or State emissions laws. Our flow tested porting, polishing, valve and valve seat work promote smoother, more efficient air/fuel flow keeping the mixture better suspended for cleaner burning. Valve spring pressure is increased for a higher max rev limit of 7000 rpm. To reduce reciprocating weight and improve acceleration we lighten and balance the connecting rods, fit stronger light weight piston pins, and lighten the flywheel. These techniques produce a 10-15% power increase and an engine which revs much more quickly. Korman Performance computer chip suggested, not required.

M20 eta P/N 110364C0

Korman 2.7 Liter Engines

The 2.7L eta engine is the ultimate in smooth, very high torque, ultra efficient performance. But the light nodular iron cast crankshaft and light valve spring pressure limit this pleasure to about 4850 rpm. Our special conversions include a high performance 2.7L crankshaft and improved valve springs which allow safe revs to 6900 rpm. This conversion is available on all of our M20 Stock, Stage 1 and 2 Competition and Stage 1 and 2 Clean Air Engines. Call one of our staff for suggestions and pricing for any applications not listed.

2.7e Standard Engine P/N 11327100
2.7eta Stage 2 Competition Engine P/N 11327370
2.7eta Stage 1 High Performance Clean Air Engine P/N 113274CO
2.7eta Stage 2 High Performance Clean Air Engine P/N 113273CO

Korman Race Engines

Whatever your series, whatever your specifications, Korman can build you a dependable, long lasting engine engineered for maximum power. Whether you need a reliable engine for BMW CCA Club Racing, or a 325 HP "conservative" race engine, call us first!

Korman Cylinder Heads

Korman cylinder heads are available prepared to the same specifications as described in our engine packages. If your engine is of moderate mileage and the bottom end is in good condition, then bolting on a Korman prepared cylinder head is a very economical and effective way of improving your engines' performance. Your cylinder head will be prepared by the same race engine technicians that build our winning race engines.

All Korman Cylinder heads are chemically cleaned, glass peened and inspected for flaws and warpage. No traces of old gasket material are left to spoil the sealing surfaces. New rocker shafts, rocker shaft clips and rocker arms are included, as are a cylinder head gasket set and Bosch spark plugs.

Our Stock Heads use all stock BMW parts and receive special attention to valve train accuracy. Shipped pre-lubricated and ready to install. Stock replacement exhaust valves with oversized valve stems are included in our Stock Heads, since they are usually required at the time of rebuild.

M20 eta Stock Cylinder Head Rebuild-P/N 11122006

If your eta engine was manufactured before Dec. '86, it has small valves, 40mm intake and 34mm exhaust. Our Stage 1 and 2 Cylinder Heads include larger valves, 42mm and 36mm, respectively.

Our Stage 1 Heads include flow tested porting and polishing, proven 3 angle valve seat work, back cut intake valves, and dual valve springs set for 7000 rpm limits. Eta engines noted above include larger intake and exhaust valves.

M20 eta Stage 1 Clean Air Cylinder Head Rebuild-P/N 11122106

Our Stage 2 Heads receive more extensive Stage 2 porting, swirl polished valves, Korman Rocker Arms, titanium retainers and dual valve springs. Eta engines include larger intake and exhaust valves.

M20 eta Stage 2 Clean Air Cylinder Head Rebuild-P/N 1122206

M20 eta Stage 2 Competition Cylinder Head Rebuild-As our Stage 2 above, plus a Schrick 272º Performance Camshaft. P/N 11122306