Engine Assembly Torque Specs

Name: VW Aircooled Torque Specifications
Creator: Aircooled Index

How tight every nut and bolt goes when you put an aircooled engine together — case nuts, rod nuts, head nuts, rocker shafts, oil pump, flywheel gland nut, pulleys and spark plugs — with thread sizes and an ft-lb / Nm toggle. Transmission and chassis fasteners are one tap away.

BUILD // FASTENER TORQUE

Nut & Bolt Torque Chart

Values are taken from the official VW manuals listed below. Rows flagged “Verify” were not found in those manuals — confirm them against the factory manual for your exact model and year.

Bentley T2 68–79 — Volkswagen Official Service Manual — Type 2, 1968–1979 (Bentley / VWoA)
VWoA 1200 61–65 — Volkswagen 1200 Workshop Manual 1961–1965, Types 11, 14, 15 (VWoA)

34 fasteners · values in ft-lb

Crankcase

Fastener	ft-lb	Thread
Crankcase Nuts (8mm)2.0 mkgSource: Bentley T2 68–79 · VWoA 1200 61–65	14	M 8
Crankcase Nuts (10mm)Verify: Not found in the official VW manuals in our library. Confirm against the factory manual for your model.	18	M 10
Crankcase Nuts (12mm)3.5 mkgSource: Bentley T2 68–79 · VWoA 1200 61–65	25	M 12 × 1.5

Crankshaft, Rods & Cam

Fastener	ft-lb	Thread
Connecting Rod Nuts3.3 mkg · 1965 1200: 3.0–3.5 mkg (21–25)Source: Bentley T2 68–79 · VWoA 1200 61–65	24	M 9 × 1
Connecting Rod Capscrews (1200, from June 1964)4.5 ± 0.5 mkg · before June 1964: 5 ± 0.5 mkg (36)Source: VWoA 1200 61–65	32	M 9 × 1
Camshaft Gear BoltsWith LoctiteVerify: Not found in the official VW manuals in our library. Confirm against the factory manual for your model.	18	—

Cylinder Heads & Valvetrain

Fastener	ft-lb	Thread
Cylinder Head Nuts (8mm stud)Verify: Not found in the official VW manuals in our library. Confirm against the factory manual for your model.	18	M 8
Cylinder Head Nuts (10mm stud)3.2 mkg · 1200: snug to 1 mkg (7), then 3.0–3.2 mkg (22–23)Source: Bentley T2 68–79 · VWoA 1200 61–65	23	M 10
Rocker Shaft Nuts8 G nuts only · 1200: 2 mkg (14) · 1600: 2.5 mkg (18)Source: Bentley T2 68–79 · VWoA 1200 61–65	14–18	M 8
Spark Plugs3.5 mkgSource: Bentley T2 68–79	25	M 14 × 1.25

Oil System

Fastener	ft-lb	Thread
Oil Pump Nut (M 6)Verify: Not found in the official VW manuals in our library. Confirm against the factory manual for your model.	9	M 6
Oil Pump Nut (M 8)2.0 mkgSource: Bentley T2 68–79	14	M 8
Oil Drain Plug3.5 mkg (1600) · 1961–65 1200: 3 mkg (22)Source: Bentley T2 68–79 · VWoA 1200 61–65	25	M 14 × 1.5
Oil Strainer / Sump Plate Nuts0.7 mkg (60 in-lb)Source: Bentley T2 68–79	5	M 6
Oil Cooler Nut0.7 mkg (60 in-lb)Source: Bentley T2 68–79	5	M 6
Oil Filler & Breather Gland Nut5.5 mkgSource: Bentley T2 68–79	40	—

Flywheel & Clutch

Fastener	ft-lb	Thread
Flywheel Gland Nut — 160035 mkgSource: Bentley T2 68–79	253	M 28 × 1.5
Flywheel Gland Nut — 1200 (1961–65)30 mkgSource: VWoA 1200 61–65	217	M 28 × 1.5
Pressure Plate to Flywheel Bolt2.5 mkg · thread as printed in the factory tableSource: Bentley T2 68–79 · VWoA 1200 61–65	18	M 8 × 1.5

Pulleys, Fan & Generator

Fastener	ft-lb	Thread
Generator Pulley Nut6.0 mkgSource: Bentley T2 68–79	43	M 12 × 1.5
Cooling Fan Special Nut5.5–6.5 mkg (1200) · 6.0 mkg (43) in Bentley T2Source: Bentley T2 68–79 · VWoA 1200 61–65	40–47	M 12 × 1.5
Crankshaft Pulley Bolt (Type 1/2 upright engine)4.5 mkgSource: Bentley T2 68–79	32	M 20 × 1.5
Crankshaft Pulley Bolt (Type 3)Verify: Not found in the official VW manuals in our library. Confirm against the factory manual for your model.	94–108	M 20 × 1.5

Intake & Exhaust

Fastener	ft-lb	Thread
Heat Exchangers at HeadSelf-locking nut · 2.0 mkgSource: Bentley T2 68–79	14	M 8
Muffler Clamp Bolts1.0 mkgSource: Bentley T2 68–79	7	M 6
Intake Manifold Nut2.0 mkgSource: Bentley T2 68–79	14	M 6 / M 8
Preheat Flange Bolt1.0 mkgSource: Bentley T2 68–79	7	M 6
Injector/Manifold bolts to cylinder headVerify: Not found in the official VW manuals in our library. Confirm against the factory manual for your model.	4	—

Engine Mounting

Fastener	ft-lb	Thread
Engine to Transmission Nut3.0 mkgSource: Bentley T2 68–79	22	M 10
Engine Bearer to Crankcase Bolt (M 8)Type 2 · self-locking · 2.5 mkgSource: Bentley T2 68–79	18	M 8
Engine Bearer to Crankcase Bolt (M 10)Type 2 · self-locking · 4.0 mkgSource: Bentley T2 68–79	29	M 10
Engine Bearer to Bearer Mounting BoltType 2 · 4.0 mkgSource: Bentley T2 68–79	29	M 10
Engine Bearer Mounting to BodyType 2 · self-locking nut · 2.5 mkgSource: Bentley T2 68–79	18	M 8
Bolts for Torque ConverterVerify: Not found in our official manuals for the upright engine. Bentley T2 lists torque converter to drive plate (1700–2000 engines) at 2.0 mkg (14).	22	—

BUILD // ENGINE GEOMETRY

Displacement & Deck Volume Tables

Displacement for common bore and stroke combinations, and deck volume by piston size for compression-ratio calculations.

Engine Displacement (cc)

Bore (rows) × stroke (columns), 4 cylinders. Highlighted cells are factory combinations.

Bore \ Stroke	64 mm	69 mm	74 mm	76 mm	78.4 mm	82 mm
77 mm	1192Stock 1200	1285Stock 1300	1378	1416	1460	1527
83 mm	1385	1493Stock 1500	1602	1645	1697	1775
85.5 mm	1470	1585Stock 1600	1699	1745	1801	1883
87 mm	1522	1641	1760	1807	1864	1950
88 mm	1557	1679	1800	1849	1907	1995
90.5 mm	1647	1775	1904	1956	2017	2110
92 mm	1702	1835	1968	2021	2085	2180
94 mm	1777	1915	2054	2110	2176	2276

Deck Volume (cc)

Volume added by deck height (piston top to cylinder top) for each piston size. Use in compression-ratio math.

Deck \ Piston	85.5 mm	87 mm	88 mm	90.5 mm	92 mm	94 mm
.030"	4.37	4.53	4.63	4.90	5.07	5.29
.035"	5.10	5.28	5.41	5.72	5.91	6.17
.040"	5.83	6.04	6.18	6.54	6.75	7.05
.045"	6.56	6.79	6.95	7.35	7.60	7.93
.050"	7.29	7.55	7.72	8.17	8.44	8.81
.055"	8.02	8.30	8.50	8.99	9.29	9.69
.060"	8.75	9.06	9.27	9.80	10.13	10.58
.065"	9.48	9.81	10.04	10.62	10.98	11.46
.070"	10.21	10.57	10.81	11.44	11.82	12.34
.075"	10.94	11.32	11.59	12.25	12.66	13.22
.080"	11.67	12.08	12.36	13.07	13.51	14.10
.085"	12.40	12.83	13.13	13.89	14.35	14.98

Every value here is calculated from bore, stroke and deck height (π/4 × bore² × length), so the numbers are exact to the rounding shown. Commonly circulated tables contain a few typos that are corrected here: 85.5 × 64 is 1470 cc (not 1496), the whole .045" deck row, and 87 mm at .050" (7.55 cc, not 6.95).

REFERENCE // OUTPUT TORQUE

Rated Engine Output Torque

Peak output torque for 57 aircooled engines — 25 with a published DIN or SAE-net rating, the rest marked as approximate family figures.

57 of 57 engines · Peak output torque · * = approximate family figure

				HP		Platform
25 hpnumeric	1131	49 ft-lb*	2000	25 DIN	43.3	Type 1, Type 2	1946–1953
30 hpnumeric	1192	56 ft-lb*	2000	30 DIN	47	Type 1, Type 2	1954–1960
34 hpnumeric	1192	61 ft-lb	2000	34 DIN	51.2	Type 1, Type 2	1961–1965
D0	1200	61 ft-lb	2000	34 DIN	50.8	Type 1	1966–1985
D1	1200	61 ft-lb	2000	34 DIN	50.8	Type 1	1966–1985
AB	1300	62 ft-lb	3000	44 DIN	47.7	Type 1, Type 2	1971–1973
AC	1300	61 ft-lb*	2600	40 DIN	46.9	Type 1	1971–1972
AR	1300	62 ft-lb	3000	44 DIN	47.7	Type 1	1974–1975
E0	1300	60 ft-lb*	2000	37 DIN	46.2	Type 1	1966–1970
F0	1300	64 ft-lb	2000	40 DIN	49.2	Type 1	1966–1970
F1	1300	64 ft-lb	2000	40 DIN	49.2	Type 1	1966–1970
F2	1300	64 ft-lb	2000	40 DIN	49.2	Type 1	1966–1970
H0	1500	74 ft-lb	2600	44 DIN	49.3	Type 1, Type 2	1966–1970
H1	1500	74 ft-lb	2600	44 DIN	49.3	Type 1	1967–1970
H5	1500	74 ft-lb	2600	44 DIN	49.3	Type 1	1968–1969
K0	1500	80 ft-lb*	2600	54 SAE	53.3	Type 3	1966–1972
L0	1500	71 ft-lb*	2000	40 DIN	47.3	Type 1, Type 2	1967–1970
M0	1500	78 ft-lb*	2600	52 SAE	52	Type 3	1966–1972
O	1500	74 ft-lb*	2300	—	49.3	Type 2, Type 3	1961–1965
ACD	1600	72 ft-lb*	2400	46 DIN	45	Type 1	1992–2004
AD	1600	78 ft-lb	2800	50 DIN	48.8	Type 2	1971–1973
AE	1600	78 ft-lb	2800	50 DIN	48.8	Type 1, Type 2	1971–1973
AF	1600	72 ft-lb*	2600	46 DIN	45	Type 1	1971–1982
AH	1600	72 ft-lb	2800	48 DIN	45	Type 1	1973–1974
AJ	1600	73 ft-lb	2800	50 DIN	45.6	Type 1	1975–1979
AK	1600	72 ft-lb	2800	48 DIN	45	Type 1	1973
AS	1600	78 ft-lb	2800	50 DIN	48.8	Type 1, Type 2	1974–1979
B0	1600	77 ft-lb*	2600	47 DIN	48.1	Type 2	1968–1970
B5	1600	77 ft-lb*	2600	47 DIN	48.1	Type 2	1968–1970
B6	1600	77 ft-lb	2800	47 DIN	48.1	Type 1	1970
C0	1600	74 ft-lb*	2600	44 DIN	46.3	Type 2	1968–1970
P0	1600	78 ft-lb*	2800	50 SAE	48.8	Type 3	1966–1967
T0	1600	81 ft-lb	2800	54 DIN	50.6	Type 3	1966–1973
U0	1600	81 ft-lb	2700	54 DIN	50.6	Type 3	1968–1973
U5	1600	81 ft-lb*	2700	54 DIN	50.6	Type 3	1971–1973
X	1600	78 ft-lb*	2700	—	48.8	Type 3	1972
CB	1700	84 ft-lb*	3200	66 DIN	49.4	Type 2	1972–1973
CD	1700	84 ft-lb*	3200	66 DIN	49.4	Type 2	1973
EA	1700	98 ft-lb*	2700	80 DIN	57.6	Type 4 (411/412), Porsche 914	1972–1974
EB	1700	90 ft-lb*	2700	72 SAE	52.9	Type 4 (411/412), Porsche 914	1973
V	1700	85 ft-lb*	3500	68 DIN	50	Type 4 (411/412)	1969
W	1700	98 ft-lb	2700	80 DIN	57.6	Type 4 (411/412), Porsche 914	1970–1971
Z	1700	85 ft-lb*	3500	68 DIN	50	Type 4 (411/412)	1969–1970
AN	1800	95 ft-lb*	3400	—	52.8	Type 4 (411/412), Porsche 914	1974
AP	1800	92 ft-lb*	3000	68 DIN	51.1	Type 2	1974–1975
AT	1800	95 ft-lb*	3400	—	52.8	Type 4 (411/412)	1974
AW	1800	92 ft-lb*	3000	68 DIN	51.1	Type 2	1973–1975
EC	1800	95 ft-lb*	3400	76 SAE	52.8	Type 4 (411/412), Porsche 914	1974
ED	1800	92 ft-lb*	3000	—	51.1	Type 2	1975
CJ	2000	103 ft-lb*	2800	70 DIN	51.5	Type 2	1976–1979
CU	2000	101 ft-lb*	3000	67 SAE	50.5	Type 2	1980–1983
CV	2000	101 ft-lb*	3000	67 SAE	50.5	Type 2	1980–1983
GA	2000	109 ft-lb	3500	91 SAE	54.5	Porsche 914	1973–1974
GB	2000	116 ft-lb	3500	100 DIN	58	Porsche 914	1973–1976
GC	2000	109 ft-lb*	3500	88 SAE	54.5	Porsche 914	1975–1976
GD	2000	101 ft-lb	3000	67 SAE	50.5	Type 2	1976–1977
GE	2000	101 ft-lb	3000	67 SAE	50.5	Type 2	1978–1979