2003 X-9 350hp MCX - Where's the horsepower?

[kylegansel]

So we just purchased a 2003 X-9 with the 350hp MCX. Absolutely love the boat. I'm a big slalom skier and the only complaint I have is acceleration and hole-shot. We used to have a '95 Maristar 200vrs with a 275 hp engine and that thing would rip you out of the water. I figured the new 350 hp would be even better but it's not. Even if I put the throttle down it still takes it's time to get out of the water. The acceleration is soft and slow and I'd like it to be better. In the engine I can see there is like this ignition switch with a dial on it? Does anyone know what that is? Curious to see if anyone else feels the same or has tried anything to get the hole-shot to be a little swifter.

[vision]

Check your prop size, then call Eric and OJ Props. The MCX in an X-9 should rip your arms off if propped correctly.

[russlars]

Check your prop size, then call Eric and OJ Props. The MCX in an X-9 should rip your arms off if propped correctly.
I'll second that response!
Bill at ACME Props can set you up with an arm puller also.:)

[bigmac]

+3. If the engine is running properly (clean the flame arrestor), soft acceleration is the prop.

[kylegansel]

So does anyone know what the ignition dial is in the engine?

[Maple Leaf]

Forgive me - I don't know you're mechanical ability - but could you be looking at a Perfect Pass servo motor knob (see attached)?

I've got the same boat as you, and she's got plenty of hole shot. Check the prop - should be a 12.5 x 12 4-blade.

[kylegansel]

Maple Leaf - Yep that's what I'm talkin' about. So that is for the perfect pass. The blade we have is a 12.5 x 13 which was the stock prop with the boat. That's not the first time I've heard I need a 12.5 x 12. Will my hole-shot be better with the 12.5 x 12 blade? Thanks for the help by the way!!!

[ProTour X9]

As long as we're prop talking why does my 06 X9 w/ MCX have a 13X12??

[Chief]

So does anyone know what the ignition dial is in the engine?



Displacement........................350 C.I.D. (5.7 litres)—350 horsepower
Bore.............................................. .................................................. ............................4.00"
Stroke............................................ .................................................. ...........................3.48"
Compression Ratio............................................. ................................................9. 4:1
Compression Pressure.......................................... ............100 PSI minimum
Maximum Allowable Compression Variation......................................... .........
Highest to lowest within 70%
Maximum Allowable RPM at WOT...............................4800-5200 RPM
Oil Pressure (Hot)............................................. .............20 PSI at 2000 RPM
Propshaft Rotation.......................................... .........................................Left-hand
Fuel Requirement....................................... .....................89 Octane minimum
Fuel Pressure: Operating Pressure.......................................... ....53-58 PSI
Fuel Pump Volume............................................ ...............1 pint in 20 seconds
Type of Fuel Induction......................................... .................................................. .........
Marine Electronic Fuel Injection Direct Port Type
Electrical System............................................ .................................................1 2 Volt
Ignition Type.............................................. .......................................Distributor HEI
Electronic Control Module....................Delco Electronics Waterproof
Marine Controller (MEFI 5)
Alternator Output Rating...................................90 amps at 2000 RPM
Thermostat........................................ .................................................. .160 degrees
Spark Plug Type.............................................. ..........................................AC41-932
Recommended Plug Gap............................................... ............................0.060"
Firing Order............................................. ...........................................1-8-4-3-6-5-7-2
Minimum Battery Rating..........750 cold cranking amps for 30 sec
at 0 degrees Fahrenheit or better
Oil Capacity.........4-5 quarts with filter change—verify with dipstick
Oil Type.............................................. ...................................SAE 15W40, CG-SJ4
Oil Filter Type.............................................. ..........................................PF25 or PZ3
Transmission Fluid Capacity..............................1 ½ to 2 qts Dextron 3
transmission fluid with 1:1 transmission; 2 ½ to 3 qts 15W40
motor oil with 1.5:1 transmission; 4.5 qts. SAE 15W40
motor oil with V-drive transmission
Initial Timing..............................10 degrees BTDC at 1000 RPM fixed;
factory set
Total Ignition Advance....Varies as a function of input information
Cylinder Numbering Front to Rear.............................................. .........................
Right bank 1-3-5-7; left bank 2-4-6-8

[Diesel]

It's a big fat boat........

Read here http://www.mastercraft.com/teamtalk/showthread.php?t=24456

The prop Eric recommends will up a smile on your face.

[Mr Incredible]

Wonder what the spec is for horsepower tolerance from Indmar?? ;)

[rodecker1978]

While we're on the topic of the MCX....does anybody know what this engine's max torque is???