Now, even with a 525, that boat is not legal for ProStock Vee. It would be only legal for SVX in OPA and any APBA affiliated organization.
The rules say that is a legal engine, OPA ProStock V rule excerpt:
Engine Build Requirements – ProStock V Class
1. ProStock V team can have their engine rebuilt by any builder of their choice. OPA MUST be notified in
advance
2. After the rebuild, the engine MUST be delivered to OPA for inspection/Dyno, to determine it is legal for
competition.
3. If the engine is determined to be legal, it will be sealed and returned to the team owner. There are no
alterations allowed to the 525 engine package.
4. Maximum cubic inch limitation of 509 cu in
5. Dyno sheets will remain with OPA
6. A standard of 560 HP will be the benchmark plus or minus 20 hp. If an engine falls short of the
benchmark the team will be notified prior to sealing.
7. OPA at its discretion has the right to Dyno any team's engine at any time. If found out of spec, the team
will lose all points for that season, and will be disqualified until such time that the engine is brought back
into spec.
8. All internal parts must remain as OEM spec.
For example if a team uses an aftermarket crankshaft, it must meet OEM spec as far as weight,
stroke, journal size, external balance, keyway location etc.
9. All Camshafts must remain the original Mercury OEM part.
10. Overbore not to exceed .030 in the engine block, any standard deck standard bore block can be used.
11. No alterations to the cylinder heads will be allowed. surfacing to the deck of the head is allowed, but the
compression must remain under 8.7.
12. Fuel system and intake plenum must remain as produced by Mercury Marine.
13. In other words the intent here is to allow the teams to be able to build their own engines as long as they
remain as a stock 525 engine package. In order to maintain parody in the ProStock V class.
14. The cost for inspection by OPA will be $800.00. The Dyno time will also be $800.00.
Approved Outdrives:
Mercruiser Bravo One, Must comply with applicable rules
Mercruiser Bravo X, XZ, Must comply with applicable rules
Mercruiser Bravo XR, Must comply with applicable rules
Mercruiser Bravo XR Sportmaster Must comply with applicable rules
Mercruiser Bravo XR Short Sportmaster Must comply with applicable rules
IMCO SC and SCX Must comply with applicable rules
And Super Vee Xtreme:
Approved Inboard Engines
Mercury Racing 525 EFI Motor, with its OEM Stock Specifications, with the following exceptions a
maximum cubic inch limitation of 510 Cubic Inches and a maximum RPM limitation of 5400 RPMS.
The SVX Class 510 CID Motor with the following specifications:
Displacement: Maximum 510 CID, with a 4” stroke crankshaft only. Crankshaft throws must be in
accordance with OEM specifications
OPA Rule Book 2019/Version 8 – 05/13/2019 Page 65
Compression Ratio: Maximum compression ratio of 9.0:1.
CAM: Any hydraulic roller cam with a maximum intake lift of .610 inch and exhaust lift of .632 inch
measured at the valve with zero lash is the only cam allowed, with an OEM stock gear timing chain,
no belt driven timing chain systems are allowed. Variable cam timing not allowed.
Block: Chevrolet designed blocks, with their OEM specifications, NO MODIFICATIONS, manufactured
by General Motors, World Products and Dart must be approved by OPA.
Materials: Crankshaft, Flywheel, connecting rods, pushrods, and wrist pins must be made of steel.
Titanium or other materials are not allowed.
Heads: The approved cylinder head is the Dart Pro I Head, Part Number 19100010M (bare head) or
19100112M (complete head with valves and springs) with their stock OEM specifications, no
modifications allowed. 1.7 ratio rocker arms on stud mounted rocker arm shafts only. The head
serial numbers must remain on the head and may not be defaced or altered. The Stock Mercury 525
OEM Head with its OEM specifications and no modifications may be used.
Intake Manifold: Any stock cast intake manifold with a Holly Carburetor 4150 style (size) base may
be used. No fabricated or tunnel ram type manifolds may be used. Intakes may be port matched up
to 1 ½ inches to match cylinder heads. Carburetor spacers or adapters are NOT ALLOWED.
Induction System: One Holley carburetor 4150 style (size) only is allowed. Naturally aspirated only,
no forced induction allowed.
Lubrication (Engine): External oil pumps or dry sump systems are not allowed.
Ignition System: Engines are required to use the MSD Digital or Analog Ignition system limited to
5400 RPMs. Crank triggers and belt drive ignitions are not allowed.
Drives:
Outdrive Specifications:
Approved Models – The Mercruiser Bravo One, XZ, XR, Sportmaster , Short Sportmaster XR, BMAX, and
Imco SC and SCX Drives are approved for competition.
The Volvo DPX Duo Prop is approved for competition.
Or am I reading it wrong?
Which is the most popular class?