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GT Pro Outboard Powerboat Racing

GT Pro is a Sportsman class created by the Twin City Powerboat Association (TCPBA) and is raced in TCPBA events.

Lined up for GT Pro racing

TCPBA conducts races in Minnesota (and sometimes surrounding states) featuring most of the national OPC classes, plus two local classes: Mini GT and GT Pro. Top speeds at TCPBA events range from 40 mph to 120 mph.

Power: 30/35hp 2-cylinder Johnson/Evinrude
Boat: Tunnel or V-bottom, 10' min.
Min. Age: 10 years old -- GT Pro rules
Dillon Pro Tunnel -- Dillon Mini Vee

GT Pro is open to tunnel, v-bottom and modified vee boats. GT Pro boats can be built of any material, and can be production-built, home-built or custom-made. The boats are powered by 30/35 hp, 31.8 cubic inch, two cylinder OMC motors with hydraulic trim and stainless steel propellers. This is serious mini-boat racing.

Local powerboat racing is a family-oriented motorsport where friends get together to share a passion. Racers are always ready to share advice, tools, equipment or muscle, and help their fellow racers get the most out of their rigs. We save the competition for the races themselves.

If you are interested in becoming a powerboat racer, or want to know more about powerboat racing in general, please feel free to contact me with your questions, or go to the TCPBA website.

If you are not prepared to build your own boat, there are
Boats For Sale.

Hydraulic Trim for Your GT Pro:

Trim is allowed in GT Pro racing, and is a nice addition to any high performance boat. The following resources will help you set up a trim system for your boat.

:: Notes on a adding trim for your OMC GT Pro motor.

:: Building a bracket for the other end of the trim cylinder -- part of my jack plate plans.

:: See also the "Setting Up" page for the Mini Vee and Pro Vee v-bottom racing boat.

Dillon Racing Stuff: T-shirts, sweatshirts, and more....

GT PRO Rules

A. Driver's Minimum Age 10 (formerly 12)
New drivers under 12-years-old will be required to take a minimum of 3 driving school sessions (to be conducted on race weekends) that include at least 5 laps on a race course by themselves. Driving school is allowed for drivers 9 years of age although they will not be able to compete until age 10. After completing 3 driving schools, driver will be on rookie status until released by a referee.

B. Motors (NOTE: see also OPC rules #24 and #25 regarding replacement parts and modifications.)
1. Any 25 horsepower (small bore carburetor), two cylinder, 31.8 cid., thru-hub Johnson or Evinrude;
2. Any 30 or 35 horsepower (large bore carburetor), two cylinder, 31.8 cid. Johnson or Evinrude is allowed.

3. Unlimited part swapping with parts origninal to the 31.8 cid. OMC powerhead is allowed.
4. Engines must be stock, -- as manufactured (no blueprinting) -- with the following exceptions
    a. Rpm limiters and oil injection systems may be removed.
    b. Electric start may be added
    c. Solid or pinned motor mounts are allowed.
    d. Tiller arms may be removed
    e. Air silencers may be removed
    f. Skeg wear bar may be removed
    g. Under-flywheel ignition may be converted to powerpack ignition using OEM or aftermarket parts/kits.
    h. Neutral start switch may be removed
    i. Cylinders may be bored .30 over and fitted with OEM oversize pistons.
    j. Reeds of any material, OEM or aftermarket, are allowed.
5. 30/35 hp only: Power trim, manual-trim or spoilers, adjustable while the boat is underway is allowed. Up to 24 volt starting system allowed.
6. Transom adapters for raising, lowering or extending the engine will be allowed, but must be fixed while underway
7. Two 1" diameter holes that can be readily plugged (for testing) may be drilled in the lower unit above the cavitation plate.
8. Cosmetic appearance of engine may be changed.
9. Engines must be securely bolted to the boat with a minimum of two bolts

C. Boats: Minimum 10'0" long and 48" wide; Minimum Weights: 30/35 hp -- 650 Lbs.; 25 hp -- 525 Lbs.
1. Boats of any material, homebuilt, custom-built or production, are allowed
2. Boats may be v-bottom, modified vee or tunnel (no hydroplanes). Four inch minimum tunnel depth at transom.
3. Drivers must be sitting in a seat at all times, using a foot throttle and steering wheel.
4. Junction of seat and seat back may not be more than 36" rearward of midships.
5. Boats must have a minimum of 3 cu. ft. of flotation foam.
6. Boats will be required to start off plane.

D. Propellers -- Any propeller, prop nut, washer and thrust washer.


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