Metric Mechanic m20 engine series e30 Magazines/Books/Booklets...

[Peter]

Introduction

Originating in Europe, the M20 Engine made its

way into the E21, 320/6 and the 323i. In 1982, the

US market received this engine in the 528e and in

1984, the 325e. Most of the M20 engines we rebuild

are installed in ‘87 and later 325i E30s - a favorite

well built model that is fairly light at around 2750

lbs. Our current HiPerformance “Baby Six” M20 engines range from a 2900 HiFlo Sport at 205 HP up

to a 3200 HiFlo ST Rally at 240 HP. See graph page 3.

Power gains from bolt-ons are usually moderate.

Large power gains come from within the engine itself. It’s done by increasing displacement, compression, head flow and camming. Lighter reciprocating

and rotating parts also enhance acceleration.

One of our 2900 Sport Engines will advance the

2750 lb. 325i to the performance level of a E36 M3.

Install a 3200 Rally Engine and that 325i is comparable to an E46 M3. See Chart 2 immediately right.

Because the E30 is fairly light, it can be revamped to

take corners faster than many other heavier BMWs,

making it an excellent track car. The drivetrain is identical to the Big Six’s of that era, so it has no trouble

coping with the added displacement and horsepower.

We offer several Ultimate Transmission rebuilds and

Variable Limited Slip Differential options to further

maximize the acceleration of your BMW.

Who are these Engines For?

All the MM Sport and Rally Engines described in

these pages are designed for daily driving as well as

track use. They run on pump gas, deliver close to

stock gas mileage, pass emissions, no loss in driveability, have a minimal noise increase, idle smoothly and

require only minor tuning in order to run right! The

average BMW enthusiast will experience only slight

behavioral differences between a stock engine and the

MM engines, except acceleration. Ours are FAST!





Metric Mechanic “Baby Six” M20 Engine Series - Revival of the Fittest! ........... 1

M20 Specification and Pricing Chart ........................................................................ 2

Reliability Before Performance ..................................................................................... 3 - 5

How Does an Engine Come to the End of it’s Life?............................................... 6

How Does Metric Mechanic Greatly Extend Engine Life?..................................... 6 - 7

2900 & 3200 Sport and 3200 Rally Pistons............................................................... 7

Bottom End Components of Metric Mechanic Sport and Rally Engines.......... 8 - 9

Evolution of the Metric Mechanic M20 Stroker Engines...................................... 10

M20 Crankshaft Use Chart.......................................................................................... 11

Metric Mechanic M20 Rods......................................................................................... 12

Metric Mechanic M20 Oil Pan Modifications.......................................................... 13

M20 Super ETA Performance....................................................................................... 14

Metric Mechanic M20 Sport and Rally Pistons....................................................... 15

Metric Mechanic HiFlo ST Sport/Rally Heads........................................................ 16