30' Spectre Set-up

[llmarine]

I am looking for help with the set-up for a 2002 30' Spectre with 2003 300X Mercurys. Current set-up is as follows:
-Manual jack plates with 51/2" of set-back
-Sport Master lower with 1:75 to 1 gears
-props turning in
-Mercury cleavers 15x34
-X Dimension I am unsure what point of reference in relation to the bottom do I check this from. Do you check from lowest point on sponson or directly in front of gear case.
-Current set-up has a lot of cavatation coming on plane and requires tunnell tab half-way down.

[skydog]

Not to sure but i think alot of the bigger Spectres like yours guys run four blade props they hook up alot better. What speeds you seeing? Have you ever spun the props out?

[Brad Zastrow]

Set your engines at neutral trim. Be very certain they are neutral. Have the engines pointed dead straight forward. Take a very long straight edge and hold to the bottom of the boat directly in front of the bullet of the drive (not the notch but the hull bottom). Now measure from the straight edge to the center of the bullet. Should be 1" to 1.5" as a start. Go up and down from there for speed. Water pressure and blow out of the props will tell you high you can go. Props turning in is usally best. I have spent days dialing in a boat moving 1/8" at a time.

You should not be cavitating like that planning off. Four blades hook up very well. You should take off hard. I am guessing you are too high. One trick I did to a 30 Motion was to vent the notch to take off faster. I ran a bilge through hull outlet on the bottom of the rear notchs with a hose running inside the hull above the water line so not to sink. Made a big difference.

[llmarine]

We've only run boat four times since we owned it and with three people approx 200 lbs each and 120 gal of fuel it ran 95 MPH GPS.

[mikesufka]

With all that weight and fuel, that actually isn't too bad.

I have a Spectre 30. Just sold my 300 Promax's and am rerigging with the new 300XS.

With my promax, my everday speed was 94-95 MPH. Toward fall with cooler temps and no weight in the boat, I'd run 97-99 MPH. Props are 15 X 32 Merc Cleavers (3 blades and NON-labbed).

The "X" motors are ~ 5-7 MPH faster than the old Promax. So, with a little "tweeking", you should see ~ 105 MPH or so.

Mike

PS: Isn't your gear ratio 1.62?