prop help!!
 

I have an issue with a 1994 Team Warlock euro 25ft, it has a gen VI 502 cu in, alum 360 cc brodix heads, sniper intake and dominator carb, I have had it out a couple of times, first time out 4000 rpms max, two people, after many trimming and trim tab adjustments did get on plane and saw speedo over 60mph, took forever to get there and was a pig getting it to plane out, next time out with 5 people, 37-3800 rpm max and was just plain slow, motor bogs, was struggling to plane out, it has a mirage 25 prop on it, this engine will make no power at all at 3500-4000 rpm, it needs to be in the 5500-6000 range, is it out of the ordinary to drop down to a 21 or 22 pitch prop? or do I need to detune it some more and change heads and intake and carb to make more torque? don't beat me up, I am new to the powerboat world, Thanks for your help!!

What compression and cam do you have ?

The Heads/Intake/Carb are more suited to a killer drag car 565cid and up. 600+cid on I/O.

Okay, not so much on the carb...but....carb for 650hp and up.

Definitely decrease pitch to get a new baseline perspective.

Brett

Is the motor getting the proper timing? I've had an ignition module go bad and not advance the timing and it was a total pig. Idk your exact specifics but it should be all in by 3000. I now run locked timing at 38 degrees. You should atleast have 32 degrees of timing in your setup.

Ok where to go next, I put a 14 1/4 x 21 michigan wheel marine cheap aluminum prop just to see if prop was my problem, it jumped on plane within feet and was able to rev quickly and sounded good, it was 60mph on gps at 5700 rpm, I am thinking a better stainless prop with a cup would help, but should I drop down another pitch size or go a little bigger on diameter to increase speed? I should be able to run it harder rpm wise, I saw 65mph with the 25 mirage plus on it but literally took half the lake to get there and would not rev at all.

You have motor issues. That boat would run the same speed (60's) with a 502/415 horsepower 502 at 5k rpm with 23" prop.

Can't tell you if motor is hurt or tuned horribly or rigged wrong, but can tell you you have wrong parts on it.

stock exhaust...

You have stock exhaust ?

Listen, you need to type clearer and provide more info.

We are here to help.

It doesn't take much to make that boat run and yours doesn't , thus why you are here asking for help.

What compression and cam ? Fuel line size, fuelp pump, psi and what is your pickup line ID and is your antisiphon valve present or gone ?

What exhaust ?