I recently finished upgrading my 1989 Bayliner 2556 from the original chevy 260 HP engine to a 383 stroker with 405 HP and 450 torque. Below are a list of things I also have changed or added:

New engine (Jeggs Marine 383 Stroker)

Removed the shift interrupt (shift assist module)

Removed the 100 lbs of ballast concrete in port side housing.

Moved salon wall 15 inches forward.

Shortened salon bench seating 10 inches.

Built new wall with 5 rack dive tank holder.

Installed sump drain for live well and dive tank well.

Replaced all through hull fittings with stainless steel fittings.

Built a free standing rear cockpit shade.

Added skiff trolling outriggers to side of fly-bridge.

Performance:

Load

5 dive tanks (approx 40 lbs each)

2 adults (340 LBS)

52 gallons of fuel

20 gallons of on board water

40 Lbs of coolers and Ice

Sea state calm with calm winds

As originally purchased OMC 260 Hp

with 15x 14p prop 3800RPM, 15 GPH, 20Kts

with 15 x 16p prop 3600RPM 14 gph 22kts.... difficulty getting on plain and small two foot waves knocked us off plane

Trim tabs needed to get on plain.

With 383 upgrade

15 x14p prop 3600RPM 12GPH 20 Kts

15 x 16p prop 3300 RPM 9-10 Gph 20 Kts 1/2 throttle

15x 17p prop 4300 RPM 18.7 Gph 29.7 Kts 80% throttle

No trim tabs used to get on plane

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