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Printed below are three
rule change proposals that were officially made public during a skiff
meeting at the APBA Summer Nationals in Hampton, VA. These proposals
seemed to be openly accepted by the majority of skiff owners that were
present. There are also a few more rule changes expected to be presented,
one pertaining to speed records for the class and one pertaining to driver
restrictions based on driver ability. When the final edit is done on those
rules I will post them here as well.
As I hinted in my last Sked Says page, new engine rules for the skiff
class have been long overdue. As I only had time to do one thing or the
other, I skipped writing an op/ed on this subject and instead opted for
getting the ball rolling. With help and input from current owners; engine
builders; parts suppliers; past and present inspectors; inboard
commissioners; and keeping in mind the wishes of some non racing skiff
owners deterred from racing because of the current engine rules, new
engine rules allowing the use of the 350 CID Chevy were developed. Issues
such as price, parts availability, inspection, and ease of
transition were top considerations. Every effort was made to keep the
power at the same levels as the two current engines, so don't misconstrue
this as a quest for more power or speed for the skiff class. Although the
basic premise of these rules will be maintained, these proposed new engine
rules are a work in progress, as minor details such as cam specs and/or
changes to the compression ratio may be made to help adjust the new engine
so it works comparably with the current engines. Speaking of the current
engines, a time frame for phasing out the engines already in use in favor
of the 350 engine is yet to be determined, an issue that will be ironed
out before the October 1 deadline for rule change submission.
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350 C.I.D Engine
All parts inside the engine must remain completely stock as furnished by
the original engine manufacturer
except as follows:
a) Block – The engine block shall be a cast iron 350 Chevrolet V-8 with a
maximum over bore of .035 inches (4.035"). The stroke shall be 3.48 inches
and the minimum deck height shall be .057" measured with a compressed
gasket from the top surface of the gasket to the top of the pistons. The
block may be align bored, decked, bored, horned, squared and deburred at
the engine builders’ discretion. The flywheel must be an automatic or
standard transmission type or optional use of an aluminum flywheel. Any
type or style of valve covers, timing chain cover or motor mounts/supports
may be used. The use of sleeves for the purpose of making repairs only,
shall be limited to (3) cylinders. Crankcase breathers may vent the engine
in any manner. Valley trays under the intake manifold are permitted.
b) Oil Pan – Any oil pan, mechanical oil pump driven off the distributor
and pickup may be modified in any manner provided the engine remains a wet
sump system and that all oil lines and hoses remain inside the pan. The
oil pan shall mean from the mounting surface of the block for the pan,
down. There must not be any modifications to the main bearing caps for
attaching of windage trays, etc., other than extended studs.
c) Crankshaft – The crankshaft shall be a stock 350 C.I.D. cast iron or
forged steel Chevrolet part with no knife edging, grooving, cross
drilling, or enlargement of oil passages permitted. Chamfering of oil
holes is permitted. Crankshafts may be chromed, reconditioned and balanced
provided no alterations are made to the standard stroke.
d) Pistons – Pistons must be original GM or stock replacements and are not
to be machined in any way other than for clearancing of wrist pins or
balancing (Wrist pin bosses or back side of piston tops). Tops may be
machined for deck clearance only and must maintain a minimum of .245" from
top of first ring land to top of piston. Pistons shall have flat tops,
four (4) valve recesses. Pressed or full floating wrist pins may be used.
Wrist pins must retain stock dimensions and weights. (Specs. to follow).
Any full compliment of rings may be used provided no alteration is done to
the ring grooves in pistons. Pistons may not be rotated 180 degrees in the
cylinder. Pistons may not be coated. Only the following non GM pistons are
legal as stock replacements: TRW / SPEED PRO # L2256F
e) Rods – Rods must be original GM or forged steel stock replacements (5.7
inches in length). Flashing removal,shot-peening and polishing rods is
permitted. Any stock replacement rod bolt and nut that fits without
machining or drilling may be used. Any replacement bearings, rod and main
may be used. Only the following non GM connecting rods are legal as stock
replacements:
MANLEY # 14101 C-8, 14101-8, 14104-8, 14112 A-8;
SUMMIT # SME-3-48-05-100, SME-3-48-05-200, SME-3-48-05B100,
SME-3-48-05B200; LUNATI # LHA1, LHAF;
EAGLE # SIR5700BPLW, SIR5700BBLW.
f) Camshaft – GM # 3972182, Crane Cams # 969551 or equivalent aftermarket
cam can be used providing it meets OEM profile under these class rules.
Stock or stock replacement solid valve lifters are permitted. Only stock
or roller type timing chain and gears are permitted. It shall be
permissible to advance or retard the camshaft from its stock position. NO
matching other than the indexing of the camshaft alignment pin and for the
mounting bolts is permitted on the timing gears.
g) Cylinder Heads – GM casting # 333882 & 3932141; World Castings #
043600; or DART # 10021070 with the following specifications:
Cast Iron, Straight Spark Plug Hole
1.94" Straight Stem Intake Valve - 11/32" Stem size
1.50" Straight Stem Exhaust Valve - 11/32" Stem size
72 cc minimum Combustion Chamber volume
Intake Port Volume: 165cc +2/- 5cc
Exhaust Port Volume: 65cc +2/- 5cc
Machining for and use of Screw in Rocker Studs and Guide Plates is
allowed.
The use of polylocks is permitted.
Any 1.5:1 Rocker Arms providing no machining required for use.
The intake and exhaust passages, as well as the combustion chamber, shall
not be ground, polished, enlarged or coated. Replacement of valve seats
and guides shall be for reconditioning only. Cylinder heads may be
machined for valves seals, screw-in or pinned rocker arm studs, marine
conversions and on contacting surfaces for the attachment to the block.
Head gaskets are mandatory. No change is permitted in the valve area,
angle of valve seat and the valves will remain in stock and shape and
size. Three angle valve seats are permitted in the head as follows: 1
approach; 1 seat; 1 bottoming. No angle is to be wider than .125". Valve
seat width must not be less than .062"
Valves must be stock Chevrolet, GM, or any OEM type valve (stainless
permitted). Swirl polished vales are permitted. Shims and any 1.250” OD
valve spring, single winding and dampener is permitted, providing no
change or machining is required for their use. Any log type, aluminum, or
water cooled exhaust manifolds must be used and all gases and water must
be mixed no farther than eight inches (8”) from the exhaust manifold
outlet and passed through the transom.
h) Intake Manifold – Intake manifold must be aluminum Edelbrock Torker II
P/N 5001 for Small Block Chevy. Runner Dimensions: 1.100" X 1.750" max. -
measured at cyl. head face. .925" X 2.500" max. - measured adjacent to
plenum area. Intake Volume: (Specs. to follow)
No porting, grinding, welding, milling or machining of any kind is
permitted except for blocking off the water cross over and heat riser, and
machining for steam vents where manifold blocks water passage in cylinder
head. Milling or changes to the shape for the attachment of the carburetor
or adapter/wedge is not allowed. Manifold must not be painted, dyed,
anodized, or in any other way finished. A carburetor wedge or adapter to
compensate for the engine angle may be used only if the total overall
height does not exceed three (3) inches. This includes any gaskets or
throttle linkage plates mounted between the intake manifold and the
carburetor. Carburetor wedges, cool cans, or other devices used to cool
the fuel are strictly prohibited.
i) Carburetor – The carburetor shall be limited to one (1) mass production
American make, having no more than four (4) venturis. The throttle plate
shall have holes no larger than 1.750 inches in diameter. Any type air
scoop or velocity stack may be used provided the air intake opening does
not face forward. This condition pertains to whether the device is
attached to the carburetor or engine hatch cover. No forward facing air
deflector for air intake. Any fuel filter and mechanical or electrical
fuel pump, with or without regulator may be used. Fuel shall be restricted
to automotive or aviation gasoline. NO additives or “trick blends” are
allowed. Standard Holley carburetor #0-4781 or HP 0-80786-1 may be used.
j) Distributor – Any distributor that fits the Chevrolet V8 engine without
adaptation is permitted. Any ignition system may be used providing no
modifications are made to any part of the engine to facilitate it's use
and the triggering system remains inside the distributor.
k) Inspections – In the event that a new record is established, the entire
engine must be completely dismantled to determine stock status and 6 point
minimum inspection for the hull. At any race other than the Nationals
and/or divisionals, the race committee can have any boat or any number of
boats inspected any may use the 7 point inspection procedure for the
engine and the 6 point inspection procedure for the hull (not to preclude
a more detailed inspection for both).
l) Jersey Speed Skiff Inspection Procedure, 350 cu. In. Chevy engine:
Will be comparable to procedures already in use for current engines.
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RUDDER RULE
Additions to: Rule 54 - JERSEY SPEED SKIFF CLASS; Section 54.1.8, as
follows:
Add to existing rule the following:
Only a single (1) rudder may be used. The rudder must be installed through
a gland or rudder port mounted through the bottom of the hull forward of
the transom.
...................................... and must be a minimum of 2 inches
forward of the transom.
Current Rule:
The rudder shall extend a minimum of 13-3/4 inches below the bottom of the
boat, measured off the true bottom (excluding any cavitation plate
adjustments). The leading edge of the rudder must not be ahead of the
trailing edges of the propeller.
Rule with proposed additions:
Only a single (1) rudder may be used. The rudder must be installed
through a gland or rudder port mounted thru the bottom of the hull forward
of the transom. The rudder shall extend a minimum of 13-3/4 inches
below the bottom of the boat, measured off the true bottom (excluding any
cavitation plate adjustments). The leading edge of the rudder must not be
ahead of the trailing edges of the propeller and must be a minimum of 2
inches forward of the transom.
Reason for change:
To keep the hull and rigging consistent with a traditional style lapstrake
runabout.
Pros: Prevents hybrid development of the boat, i.e., crossing hydro
technology with a runabout. Outboard rudders are not necessary for
improved handling characteristics over conventional inboard runabout
styles and are generally seen as inferior to conventional styles in
cornering abilities.
Cons: Some owners will have to change their existing set ups to comply.
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STEP RULE
Addition to: Rule 54 - JERSEY SPEED SKIFF CLASS; Fig. 1 - Jersey Speed
Skiff Hull Dimensions, as follows:
Add sentence to bottom of existing rule as follows:
No transverse breaks or steps are permitted on the sides of the hull.
Current Rule:
A minimum of 6 planks or strakes per side and being a minimum of 3/8"
thick, except at transom and stem. No simulation by paint or scribed
lines.
Rule with proposed addition:
A minimum of 6 planks or strakes per side and being a minimum of 3/8"
thick, except at transom and stem. No simulation by paint or scribed
lines. No transverse breaks or steps are permitted on the sides of the
hull.
Reason for change:
To keep the hull consistent with a traditional style lapstrake runabout.
Pros: Prevents hybrid development of the boat, i.e., crossing hydro
technology with a runabout. Steps are not necessary for improved handling
characteristics over conventional designs.
Cons: Some owners will have to fill in steps to comply.
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