SDI (engine)


The SDI engine is a design of naturally aspirated direct injection diesel engine developed and produced by Volkswagen Group for use in cars and vans, along with marine engine and Volkswagen Industrial Motor applications.
The SDI brand name was adopted in order to differentiate between earlier and less efficient indirect injection engines, called SD or "Suction Diesel", which were also produced by Volkswagen Group.
SDI engines are only produced in inline or straight engine configurations; and as they originate from a German manufacture, are designated as either R4 or R5, taken from the Reihenmotor. They are available in various displacements, in inline-four and inline-five, in various states of tune, depending on intended application.
The SDI engine is generally utilised in applications where reliability and fuel economy are of primary concern. These engines lack any type of forced induction, hence the use of 'suction' in the title, and as such, their power output is lower when compared with a similar displacement turbocharged engine. For example, the 2.0 SDI engine fitted to the Volkswagen Golf Mk5 has a peak power output of ; whereas the same engine in Turbocharged Direct Injection form is rated at or, depending on specifications.

SDI engines and applications

Lubricants

Like their related Volkswagen Group Turbocharged Direct Injection diesel engines, Volkswagen AG requires that motor oil lubricants for SDI engines must only meet VW505.00, 505.01, 506.00, 506.01, or 507.00 officially approved standards. 'Generic' oil standards such as the American Petroleum Institute 'API', or European Automobile Manufacturers Association 'ACEA' are not recognised, nor approved by VW - so oils bearing these generic approvals must not be used, except when the oil has also been granted one of the specific VW approvals.
Many formulations of motor oils from most brands are now "VW Approved" to the above standards. However, there does exist a few unapproved 'off brands' that print the VW number on the label, effectively 'claiming' to meet the said standard, but hide in small type the word "recommended". Volkswagen AG only carries out in-house testing on motor oils to grant the necessary approvals; if Volkswagen AG, therefore, has not carried out such tests, Volkswagen AG will not grant approval. Volkswagen Germany freely publish up-to-date lists of currently approved oils on their respective websites, along with the technical resource, erWin. Volkswagen AG does not permit any independent testing facility to grant their own VW standards.
All SDI-engined models with "LongLife Servicing", "Extended Service Intervals", "ESI", or "WIV", must be run on official 'LongLife' lubricants, namely VW506.00, VW506.01, or the very latest VW507.00. Again, other 'generic' longlife lubricants should not be used, unless they also have the official relevant VW LongLife approval.

SDI vs other VW Group diesel engines

The following table contains a selection of current and historical Volkswagen Group compression-ignition SDI diesel engines for comparison of performance and operating characteristics with other naturally aspirated and forced induction engines of the same capacity:

engine
model
engine
displacement
engine configuration
& diesel fuel system
valvetrainmax.
power:
kW
rpm
for
max.
power
max.
torque:
Nm
max
MEP:
bar
MEP @
max.
power:
bar
max
operating
revs:
rpm
dates
installed
'inline 4, indirect injection
mechanical distributor injection pump
8v
SOHC
35
4,50082
2,700 - 3,50025.2
5,000Polo 2, 2F
late 1980s -
early 1990s
'inline 3, turbo direct injection
mechanically pressurised, electrically triggered pumpe-duse unit injectors
12v
SOHC
59
4,000195
2,20041.5
Polo Bluemotion, first generation
2006 -
2010
'inline 4, indirect injection
mechanical distributor injection pump
8v
SOHC
42
4,500103
2,80024.5
10/1986-
05/1992
'inline 4, direct injection
electronic distributor injection pump
8v
SOHC
44
4,200115
2,20025.6
07/1996-
07/2005
'inline 4, indirect injection
mechanical distributor injection pump
8v
SOHC
47
4,300124
2,500-
3,200
24.8
'inline 4, indirect injection
electronic distributor injection pump
8v
SOHC
36
3,000121
1,80019.0
current
'inline 4, direct injection
electronic distributor injection pump
8v
SOHC
50
4,000133
1,80026.4
current
'inline 4, indirect injection
mechanical distributor injection pump
8v
SOHC
55
4,200150
2,00029.0
'inline 4, direct injection
electronic distributor injection pump
8v
SOHC
66
3,750210
1,90034.8
'inline 4, direct injection
Pumpe Düse Unit Injector
8v
SOHC
96
4,000310
1,90050.6
current
'inline 4, direct injection
Pumpe Düse Unit Injector
8v
SOHC
55
4,200140
2,40027.9
current
'
140 PS
inline 4, direct injection
Pumpe Düse Unit Injector
8v
SOHC
103
4,000320
1,80052.3
20.4315.70current
'
170 PS
inline 4, direct injection
Pumpe Düse Unit Injector
16v
DOHC
125
4,200350
1,800-
2,500
63.5
current
'
170 PS
inline 4, direct injection
common rail
16v
DOHC
125
4,200350
1,750-
2,500
63.5
current
'
75 PS
inline 5, direct injection
electronic distributor injection pump
10v
SOHC
55
3,600155
2,25022.3
02/2002-
current
'
163 PS
inline 5, direct injection
common rail
10v
SOHC
120
3,500350
2,00048.8
current

174 PS
inline 5, direct injection
Pumpe Düse Unit Injector
10v
SOHC
128
3,500400
2,00052.0
20.4317.84current
engine
model
engine
displacement
engine configuration
& diesel fuel system
valvetrainmax.
power:
kW
rpm
for
max.
power
max.
torque:
Nm
rpm
for
max.
torque
specific
power:
kW/L
max
MEP:
bar
MEP @
max.
power:
bar
max
operating
rpm
dates
installed