|
Component |
1990 Engine |
1993 Engine |
Exhaust Manifold
Gaskets |
Standard composite
gasket similar to a head gasket in construction |
Two-layer thin metal
gasket. |
Exhaust Manifold
Studs |
All exhaust manifold
studs are the same diameter (M8). |
The two lower studs
on the ends are larger (M10) than the rest of the
studs (M8). |
Throttle Body |
|
Some of the throttle
body sensors have been repositioned. |
Throttle Body
Mounting Studs |
Mounting studs are
located in the front (closer to engine) positions
and bolts in the rear. |
Mounting studs are
located in the rear positions and bolts in the
front. This makes installation of the manifold
brace easier. |
|
|
Component |
1990 Engine |
1993 Engine |
Block |
|
There are numerous changes to the block. |
Bearing Inserts |
|
Both the main and
rod bearing inserts are narrower than the 1990
versions. Because of this they are no longer
interchangable. I have found that the
manufacturers I've tried to buy bearings from do
not show a difference for 93-94 engines. They
still think the 90-94 engines are all the same!
Ignorance is such bliss... |
Connecting Rods |
Identification
number is G6 |
Identification
number is ??. The main portion of the rods
are thinner than the 1990 rods. There appears to
be less metal on the big end also. This should
result in a significant weight reduction. |
Crankshaft |
The "big end" (where
the flywheel is) has 6 bolts.
|
-
The big end has 7
bolts and is about 8mm larger in diameter than
the 1990 crankshaft.
-
Weighs less due to
smaller counterweights.
-
Main and rod
bearing journals are narrower than the 1990
journals.
|
Crankshaft Big End
Oil Seal |
|
The seal is about
1/4 larger in diameter than the 1990 seal. |
Crankshaft Main
Bearing Caps |
The #1 and #2 bearing caps are connected together
(as are the #4 and #5 caps) with one thick metal
beam that is situated below the center of the
caps. The #3 thrust bearing cap is completely
separate from the others. |
All bearing caps are
connected by two thick metal beams that are
situated below and to the left and right of the
caps (when looking at the engine from either end).
|
Flywheel |
6 bolts.
Identification number 63GT is cast into the
flywheel on the engine side.
|
7 bolts.
Identification number 63TK. The diameter is about
8mm smaller than the 1990 flywheel. The clutch is
exactly the same size, however.
Note: This could be a
difference between FWD and AWD. Anyone know? |
Oil Cooler |
There are two
threaded ports for an external air-cooled oil
cooler. There are two smaller access ports that
are blocked with large allen head plugs. |
Has a water-cooled
oil cooler bolted between the housing and the oil
filter. The external cooler ports are gone, but
the two smaller access ports are still there. |
Oil Pick-Up Tube |
|
The shape of the
pickup screen has changed and the pickup tube
extends further into the oil pan by about 15mm. |
Oil Pump Gears |
The gears are
straght cut. This accounts for the whine sometimes
heard when first starting a cold engine. |
The gears are spiral
cut, thus eliminating the former whine at startup. |
Oil Pump Gear Cover |
|
One of the 5
mounting bolt holes has been moved relative to the
1990 version. The rest remains the same. Because
of this modification the two years are no longer
interchangable. |
|
Oil Seal Case |
The case has a lip
around the outside of the oil seal that makes it
necessary to remove the case to change the oil
seal. |
The case is modified
to accept the larger sized oil seal. The oil seal
can be removed from outside the engine without
removing the case. The cases are not
interchangable between blocks of different years. |
Pistons |
|
Turbo piston
identification number is G63TK (lighter
than G63T?) |
Front Casing |
|
There are several
modifications to the front casing making the two
incompatible. I will list them soon. |