M10 4 Cyl SOHC*

Models: 2002, 2002tii, 320i, 318i≥ '85
*Single Overhead Cam
EngineHorsepowerPriceCore Deposit
E1 - MM 2200 Rally Engine185 HP$13,000$1,500
Additional Charge for a 2002tii$300
Additional Charge for an 80mm 2 Liter Crankshaft:
For 1.8 320i and 318i (1980 - on)
Options: for the 2200 Rally Engine
MM Lightened 13 lbs. Stock 228 mm Flywheel & High Torque Clutch Assembly with 9 strapping bands$950$400
MM 11.5 lb Billet 228 Steel Flywheel & High Torque Clutch Assembly with 9 strapping bands$1,200
Carburetor Kit, MM Weber 38 DGES Kit
and matching manifold
$1,500Manifold core deposit $400
Alternator Bracket Upgrade: 2002 tii$300
E2 - MM 2100 Boosted Engine14 lbs (1 Bar) 350 HP$15,000$1,500
Options: for the 2100 Boosted Engine
MM 13.5 lb 240 Flywheel & High Torque Clutch Assembly with 9 strapping bands$1,500

MM 2200 Rally M10 engine

The MM 2200 Rally engine is a very reliable 160hp street/track engine that is modernized with many mechanical improvements. This is general description of the engine.


  • 2130cc = bore 92mm x stroke 80mm
  • Compression Ratio 10.0:1


  • Machine ported for a 22% flow increase over stock
  • MM’s patented Surface Turbulence looks like concentric grooving. It is done to the valves and combustion chamber walls. This increases fuel economy, makes for a cleaner running engine and reduces detonation to prevent head cracking. 
  • New inspected rocker arms
  • MM Sport/Rally cam is 290° duration with 10.75mm lift. This cam produces a broad power band and a smooth idle when used with a Weber 38 DGES carburetor.
  • MM special dual valve springs prevent valve bounce at high rpm by increasing the seat pressure and prevent valve train wear & rocker arm breakage by lowering the nose pressure.
  • Manganese bronze valve guides.


  • MM forged 92mm piston is very light but strong at 300g (stock piston is 500g). 
  • Taper wall piston pin weighs 89g vs 135g stock.
  • Moly 1.2mm Compression ring and 3 piece oil rings, for long life and low Oil consumption.
  • Rod is a light weight 525g “H” beam design, that is 143mm long (8mm longer than stock).
  • Rod and Main bearing are dry film Moly coated.
  • New timing chain, oil pump chain, guide, and tensioner rail.
  • MM rebuilt and blueprinted oil pump with bronze bore for the pressure relief valve.
  • Oil pan baffle has a horizontal baffle to prevent oil starvation under hard cornering.

All clearances in the engine are measured down to .0001” or .01mm and recorded. The engine is fully blue printed.

2300 Rally Engine   This engine is totally streetable but is designed for a more aggressive driving style. It is an excellent choice for hard street driving, auto crossing or driver’s schools. Displacement is increased by stroking the engine with a modified 2.3 liter/S14/84mm crankshaft. The total reciprocating mass (piston and rod assembly) is 4 lbs. lighter than a stock BMW M10 engine. Not only does the lightweight reciprocating mass help this engine to spool up quicker but it reduces vibration at high RPMs and adds longevity. This engine is generally meant to run with no air conditioning but for an additional $500, we can install the AC pulley. Currently our most popular engine, a great “bang for buck” designed for the week-end warrior who enjoys Driver’s School events.
2400 Rally Engine   A lighter longer stroked crankshaft is added to this engine – the Evo M3/2.5 liter 87mm crankshaft. If you desire the Biggest most powerful street/track engine that we offer in an M10 Engine – this is IT! The 2500 comes with a broad power band. In a track event such as a Driver’s School, this engine spools up quickly and then pulls hard of corners as well as down the straight away. When on the street – it’s the hottest we make – Period!

ALL our Sport & Rally M10 Engines have the following mechanical upgrades —

  1. Machined and hand ported head with 21% to 24% flow increase.
  2. Surface Turbulence treatment to the Head reduces detonation, virtually eliminates head cracking, results in greater fuel economy and lower emissions.
  3. Sport Camshaft that offers good idle and driveability.
  4. Single Row Timing Chain for increased life and less parasitic loss.
  5. Rocker Arms: inspected and 30% stronger than stock.
  6. Lightweight “Bee Hive” Valve Springs & Retainers to reduce Valve Train load.
  7. Manganese Bronze Valve Guides for tighter valve stem – to guide clearance and extended guide life.
  8. Moly Top rings and 3 piece Oil Rings for good oil control & long life
  9. Rally Engines have special Heavy Duty Tri-Metal rod bearings.
  10. Blue Printed Oil Pump with bronze pressure relief valve sleeve or aluminum body oil pump. For greater oil pump life and improved oil volume.
  11. Horizontal Oil Baffle in the Oil Pan, to prevent oil starvation under hard cornering.
  12. Optional Windage Tray/Scrapper Bar for even more oil protection under hard cornering. Strongly recommended for Driver’s Schools. Additional $350
2200 & 2300 FI Engines    These engines, designed specifically for boost, are capable of the high 200 and 300 HP range with as little as 10 – to 12 lbs. of boost. Built tough to take boost pressure and the additional heat and pressure generated in the combustion chamber. For example, from the Ceramic Coated piston through to the Forged Chrome Moly Crankshaft, these two are seriously beefed up. Both engines are virtually identical except for their stroke. The 2200 FI Engine has an 84mm Stroke whereas the 2300 has an 87mm stroke making it the most powerful M10 engine we offer. To avoid any confusion, Metric Mechanic does not sell the Boost System itself or provide the Tuner. We build the engines that can take it.

In addition to the above modifications and those included in our Sport & Rally Engines, all our Forced Induction Engines offer the following upgrades.

  1. S14, 84mm Chrome Moly Forged Steel Crank for the 2200 Forced Induction Engine or the 87mm for the 2300 FI Engine.
  2. Stronger “H” Beam rods 565 grams have 4 oil squirter grooves located at the big end to cool off the piston and lubricate the piston skirt.
  3. Special coated tri-metal rod bearings.
  4. Special Forced Induction Forged Pistons. Ceramically coated Piston Crown is 2mm thicker than in the Sport and Rally Piston.
  5. High Silicon Content Alloy (13%) for tighter cylinder wall
  6. clearance, greater ring and groove life, & minimize skirt scuffing.
  7. Lower placement of the top ring groove to protect the compression ring.
  8. 4mm oil ring for excellent oil control.
  9. Over-sized 23.5mm Wrist Pins, 115 grams.
  10. The oil pump delivers 20% more flow.
  11. All Forced Induction M10 Blocks are ultrasonically tested and hand selected for cylinder wall strength.