[Engine]     [Fluids & Capacities]     [Performance]

Eta Specifications

Engine
The official BMW code for the 2.7 liter Eta engine is M20/B27.  Because it was designed during the Seventies' fuel crunch, the Eta (Greek letter denoting effeciency to engineers) was tuned for maximum effeciency and fuel savings.  The BMW engineers used fewer cam bearings, softer valve springs, and a cam/chip package which was tuned for lean running to accomplish their goal of good fuel economy.

However, as not to strip all of the fun from the car, the Eta motors were tuned to be torque engines.  As you can see in the following specifications, they don't have too much horsepower, but they have gobs of torque.  The torque curve is also very flat.  This is readily noticeable, as you can pull almost any gear, regardless of speed.
 
1984-1987 325, 325e, 325es
1988 325
Number of Cylinders
6
6
Bore (mm)
84.0
84.0
Stroke (mm)
81.0
81.0
Displacement (cc)
2693
2693
Compression Ratio
9.0:1
8.5:1
Horsepower SAE net @RPM
121 @ 4250
127 @ 4800
Torque lbs.-ft. SAE net @RPM
170 @ 3250
170 @ 3200
Fuel injection system
Bosch Motronic
Bosch Motronic 1.1
Fuel Required
unleaded 87 octane
unleaded 87 octane
*Adapted from the Bentley 3-Series Service Manual


Fluids & Capacities
Fluid
Approximate Capacity
Specification
Engine Oil 
325, 325e, 325es
with filter change
4.0 L (4.2 qt.)
4.25 L (4.46 qt.)
API service SE or SF
Manual Transmission Oil
1.25 L (1.32 qt.)
SAE 80, API GL-4, MIL-L-2105 (non-hypoid type)
Automatic Transmission Fluid (ATF)
3.0 L (3.2 qt.)
Dexron or Dexron II ATF
Final Drive
1.7 L (1.9 qt.)
SAE 90, GL-5
Power Steering Fluid
permanently sealed, no drain plug
Dexron or Dexron II ATF
Brake Fluid
as necessary (it took less than 1 L to flush and fill my system)
DOT 4
Engine Coolant
12.0 L (12.7 qt.)
50% phosphate-free ethylene glycol anti-freeze
* Adapted from the Bentley 3-Series Service Manual

Spark Plug                Electrode Gap
    Bosch WR9LS            0.7 ± 0.1 mm (0.027 ± 0.004 in)
 
 
Wheels
Tires
Tire Pressures f/r (psi)
Heavy Load Pressures (psi)
5½J x 14 H2
195/60 HR 14 85H
31/32
32/36
6J x 14 H2
195/60 SR 14 85Q M+S
195/60 HR 14 89H
195/65 SR 14 89Q M+S
195/65 R 89Q M+S
195/65 R 14 89H
31/31
31/31
31/31
29/32
29/32
31/36
31/36
31/36
31/36
31/36
6½J x H2
 195/65 R 14 89Q M+S
195/65 R 14 89H
29/32
29/32
31/36
31/36
150 TD 365
200 60 SR 365 88Q M+S TD
200/60 HR 365 88H TD
31/31
31/31
31/36
31/36
 *Adapted from the Bentley 3-Series Service Manual

Notes on Tires

Tires are normally classified in the format:  xxx/yy AA zz
    Where:

 Q
S 
T 
U 
H 
V 
W 
Y 
Z 
99 mph
112 mph
118 mph
 124 mph
130 mph
149 mph
168 mph
186 mph
149+ mph
For more information on tires, take a look at The Tire Rack's excellent web site.


Performance
Acceleration:
Time to distance, sec.
0-100 ft.
2.6
0-500 ft.
8.8
0-1320 ft. (¼ mi.)
16.6
Speed at end of ¼ mi, mph
81.5
Time to speed, sec:
0-30 mph
2.5
0-60 mph
8.9
0-80 mph
15.7
0-100 mph
35.0
Top speed, mph
est 122
Trip fuel economy, mpg
28.0
Brakes:
Stoppping distance, ft., from:
60 mph
153
80 mph
258
Pedal effort for 0.5 g stop, lb.
26
Fade; % increase in effort
6 stops from 60 mph @ 0.5g
nil
Overall brake rating
excellent
Handling:
Lateral acceleration, g
0.79*
Slalom speed, mph
58.0
Interior noise, dBA:
Idle in neutral
51
Maximum, 1st gear
71
Constant 30 mph
61
50 mph
65
70 mph
72
From Road & Track, June 1984     *From Motor Trend, June 1984

Despite the estimated 122 mph top speed, I reached an indicated 130 mph on the Montanabahn.  My 325e felt as planted at that speed as it does at 70 mph!