1938 Cadillac V16 - GM Heritage Center

10
Cadillac-LaSaile Preliminary Service Information
Carter carburetors are used on LaSalle 38-50
engines and Stromberg carburetors on the 38-
series Cadillac V-8 engines. These carburetors are
the same as those used on 37-series, with the
following improvements:
On the Carter carburetor, more accurate calibration
of the fuel-air ratio, accomplished by nozzle
changes, improves part throttle operation. The
action when cold is aided by a slower decrease
in choking as the engine warms up.
A change has been made in the anti-percolator
adjustment on Carter carburetors. The marks on
the jets should be .015" above the tops of the
housings instead of fluFh with them as previously
required.
On the Stromberg carburetor, a vacuum-actuated
economizer is employed in place of the former
throttle pump. This device enriches the mixture
whenever more power is required, even though
the throttle is not fully open. Whenever the
engine is pulling under load, the resulting low
vacuum in the intake manifold acts directly to
supply the added fuel required.
There is no change in service or ad justments of
the Stromberg carburetor.
The three point rubber mounted engine supports
previously used are continued for the 38-series
V-8 engines. The transmission extension support
has been moved rearward on 38-60, 65 and 75 to
accommodate the new frames and provide interchangeability
between the various Cadillac series.
Two large flat washers ^j-inch thick are placed
between the top plate and the rubber cushion at
38-65 and 75 rear support. Series 38-50 and 60
continue the use of a single )^-inch washer at this
point.
V-i6 Engine
38.90
Angle between cylinder blocks 135°
Cylinder firing interval 45°
Bore and stroke 3¾ x 3½"
Piston displacement
431 cu. in.
Compression ratio 7.0 to 1
Horsepower:
Taxable 67.6
Developed at 3600 R. P. M 185
Crankshaft and Main Bearings:
Counterweights
8, integral
Damped flywheel No
Harmonic balancer
Yes
Main bearings, diameter 2H"
Main bearings, number 9
Main bearings, type
Shell
Connecting Rods:
Arrangement on crankpin
Side-by-side
Bearing diameter 2"
Bearing type
Shell
Length of rods 6%"
Pistons:
Design ;• T-slot
Material
Anodized Aluminum Alloy
Compression rings, number 2
Compression rings, width Jtj", A"
Oil rings, number 1
Oil rings, width
&"
Piston pin
Locked in rod
Timing Chain:
Adjustment
None
Length 23½"
Links, number 62
Pitch H"
Width 1¾"
An entirely new V-16 engine has been designed
for the 38-90 series cars, which will supersede
both the 37-85 and 37-90.
The outstanding new feature of the 38-90 engine
is the en bloc design, with a single casting of grey
iron for cylinders and crankcase, and an angle of
135° between the cylinder banks. This arrangement
results in an engine that is more compact,
more durable, and more efficient than previous
V-12 and V-16 engines.
Valves:
Arrangement
L-head
Seat angle 45°
Seat diameter, intake
1¾'
Seat diameter, exhaust 1M"
Tappet clearance
Automatic
Engine Lubrication:
Oil pump
Helical Gear
Crankcase oil capacity
11 qts.
Ignition:
Coils, Delco-Remy No
553 E
Distributor
Contact point gap 0125-.0175*
Contact arm spring, tension
19-23 oz.
Firing order 1,4,9,12,3,16,11,8,15,14,7,6,13,2,5,10
Spark Advances (degrees on flywheel):
Manual advance on distributors 20°
Automatic advance (maximum) 28°
Spark Plugs:
A. C. type number 45
Gap 025-030"
Thread
14mm.
Carburetion:
Carburetors (two used):
Make
Carter
Size 1¼"
Type
Dual downdraft, plain tube
Engine Number Location:
On the upper rear left hand corner of the left hand
cylinder block, parallel with the cylinder head.
Although the 38-90 engine develops about the
same horsepower as the 37-90, the stroke is shorter
and the piston displacement is only 431 cubic
inches. The overall length and the weight of the
complete power plant are less than those of the
37-85 as well as the 37-90. Performance is improved
because the 38-90 complete cars weigh
about 1000 pounds less than corresponding 37-90
cars.