I have a recently reconditions 1990 spectra XL that has a fresh 7.4 that has been slightly bumped up to around 370 HP, The prop that came on it is a mirage 2 19p that pushes the boat about 57mph straight out, engine turning about 4700rpms. I put a 21p mirage 2 on yesterday and went 58.5 straight out engine turning 4500 rpms. I am looking for the 65 range but don't have a clue how to get their. Same load on the boat both times. Any suggestions would be great.

I had a 1995 Spectra XL with a 454 mag (365 horse). I put 496 aluminum manifolds on the motor which gained me about 1 mph top end.

With a Mirage 23 pitch I would run 59 mph. So I would think you are running just about the right speed with your combo.

To get to 65 mph you will need approximately another 150 horsepower. Easiest way is a Procharger. I would budget for about $10,000 to set it up right and not blow your motor.

Also your boat hull has a wedge built into the bottom between the two outermost strakes at the transom. This will really hold the boat back as far as top speed. Place a straightedge on the bottom from the transom forward and you will see what I mean. Removing the wedge may result in some ill handling effects and hurt resale.

Use the search engine on this website and you will find lots of info concerning the wedge and horsepower increase versus mph increase.

Also the 222xl is a great boat. Just not the fastest hull per horsepower out there.