1991 ACURA NSX gas type

Exhaust System

Dual Exhaust System

A compact dual exhaust system is used to provide low back pressure.
Sound tuning has been optimized to give a sporty exhaust sound note suitable to this type of car. This is done by a col-
lection chamber in muffler.
MUFFLER

REAR
EXHAUST

PIPE

REAR EXHAUST

MANIFOLD

FRONT THREE WAY CATALYTIC

CONVERTER

REAR THREE WAY CATALYTIC

CONVERTER

FRONT
EXHAUST

PIPE

FRONT EXHAUST

MANIFOLD

Exhaust gas
from
rear bank

COLLECTION CHAMBER

Exhaust gas

from

front bank

FeaturesProCarManuals.com

Cylinder Heads
Installation (cont'd)
Rear:
8 x
1.25
mm
22 N .
m
(2.2 kg-m,
16 Ib-ft)

HEATED OXYGEN

SENSOR

45 N .
m
(4.5 kg-m,
33 Ib-ft) Be careful not to damage.

GASKET
Replace.

REAR EXHAUST
MANIFOLD

EXHAUST

MANIFOLD

COVER
SELF LOCKING NUTS
8 x
1.25
mm

34 N .
m
(3.4 kg-m,

25 Ib-ft)

Replace.

3. Install the cylinder heads on the engine block. The cylinder head dowel pins and the head oil con-
trol orifice must be aligned.

CYLINDER HEAD

GASKET (METAL)
Replace.
CYLINDER HEAD

GASKET (METAL)

Replace.

HEAD ORIFICES

DOWEL

PIN

DOWEL PIN
O-RING
Replace.
DOWEL

PINS
CYLINDER HEAD BOLTS

11 x 1.5 mm

78 N .
m (7.8 kg-m. 56 Ib-ft)

Apply clean engine oil to the bolt threads and washer contact

surfaces.

CYLINDER HEAD BOLTS TORQUE SEQUENCE

Specified Torque

11 x 1.5 mm

78 N .
m (7.8 kg-m, 56 Ib-ft)
NOTE: We recommend using a beam-type torque
wrench. When using a preset-type torque wrench,
be sure to tighten slowly and not to over-tighten.
Always use a new cylinder head gasket. Apply clean engine oil to the bolt threads and
washer contact surfaces.
4. Tighten the cylinder head bolts sequentially in two
or three steps.ProCarManuals.com

SNAP RING
WASHER
THRUST NEEDLE BEARING MAINSHAFT 4TH GEAR
NEEDLE BEARINGS
MAINSHAFT 4TH GEAR COLLAR
THRUST NEEDLE BEARING
THRUST WASHER 4TH CLUTCH ASSEMBLY
O-RING Replace.

MAINSHAFT

SEALING RING 37 mm
NEEDLE BEARING SET RING
REVERSE SHIFT FORK
LOCK WASHER
Replace.
COUNTERSHAFT REVERSE GEAR COLLAR
THRUST WASHER
COUNTERSHAFT REVERSE GEAR
NEEDLE BEARING
REVERSE SELECTOR
REVERSE SELECTOR HUB
COUNTERSHAFT 4TH GEARNEEDLE BEARING (Separate type)
COTTER RETAINER
COTTERS
COUNTERSHAFT 2ND GEAR SPACER
COUNTERSHAFT 2ND GEAR
THRUST NEEDLE BEARING
COUNTERSHAFT 3RD GEAR
NEEDLE BEARING
THRUST NEEDLE BEARING
COUNTERSHAFT 3RD GEAR COLLAR3RD CLUTCH ASSEMBLY
O-RING
Replace.
COUNTERSHAFT
SPACER 31 mm
2ND CLUTCH ASSEMBLY
O-RINGS
Replace.
THRUST WASHER
THRUST NEEDLE BEARING
SECONDARY SHAFT 2ND GEAR
NEEDLE BEARING
THRUST NEEDLE BEARING
SECONDARY SHAFT
SEALING RING 35 mm
DIFFERENTIAL OIL SEAL
Replace.
REVERSE IDLER GEAR SHAFT/HOLDER
REVERSE IDLER GEAR SHAFT SPRING
STEEL BALL (7/32) 7
NEEDLE BEARING

TRANSMISSION HOUSING
REVERSE IDLER GEAR
CONNECTOR STAY
SEALING WASHER
Replace.

THRUST SHIM

BEARING OUTER RACE
SNAP RING
SECONDARY SHAFT BALL BEARING
COUNTERSHAFT BALL BEARING
MAINSHAFT BALL BEARING
GASKET
Replace.
DOWEL PIN
DIFFERENTIAL GEAR ASSEMBLY
BEARING OUTER RACE

THRUST SHIM

DIFFERENTIAL OIL GUIDE RING
2ND CLUTCH FEED PIPE
1ST-HOLD CLUTCH FEED PIPE
4TH CLUTCH FEED PIPE
1ST CLUTCH FEED PIPE
3RD CLUTCH FEED PIPE
TORQUE CONVERTER HOUSING DRIVESHAFT OIL SEAL
Replace.
TORQUE SPECIFICATIONProCarManuals.com