My 18' Formula weighed 3500# with full tank and small block. Yours is much heavier, really should be a big block boat with bravo. Friend had one on Cayuga lake like yours and believe with the 260 hp the most he saw was 43.

Jasper's rating did not include water pump, accessories, and probably used dyno headders, I think your combination with these losses would bringe you down to the 300 hp level.

Merc used to rate the standard 7.4 liter carb engine at 330 HP, but that was at the crank, when they switched to propshaft rating (all accessories and drive losses) the new rating was 310 hp.

My avaitar shows killer 406ci small block with Brodix Track II 2.02 aluminum heads, single plane manifold, 750 dual line holley, solid lifter Ultradyne cam, and Stainless Marine manifolds. It would pull a 27 pitch 4 blade hydromotive prop like it was nothing. It killed the drive in the second season even when babying the throttle. Top speed was 70 to 72 at 4600 rpm, but the boat chine walked badly. Pulled all the cam out of it, went down to a 600 cfm carb and then sold it with a top speed of about 60, just so the new owner didn't kill themselves.

I am starting to think you guys are right, that it just needs a big block. I thought that upping the small block from 260 horse to 325 horse would do the trick, but I guess this thing was absolutely horrible with the original 260.

I am going to try and step down to a 17" Mirage prop and see what it does. This motor needs to turn RPM to make power. I just don't understand the white plugs, thats why I wanted to try a Holley 750.

Will overloading the motor with too much weight and too big of a prop cause lean white plugs???

Well, I decided to try and step down to a 17 pitch prop, to get the RPM's up. I guess this motor needs to really spin to make power. I picked-up a Mirage 17 today, and hopefully it will help. I'm sure my holeshot will improve. I'll post the results tomorow.

Thanks again guys for your advice, I appreciate

I think you need a good holley 600 and put the timing to atleast 36 or 37 degrees. Hell on my old 355 with steel dart heads and almost 11-1comp I ran 38 degrees and it made an honest 450hp.

Well, I stepped down to a 17 pitch Mirage prop, and it made a huge difference. Now it turns 4800-4900 RPM's at 47 MPH on the GPS. It comes out of hole ten times better also. Now when I nail the throttle it actually takes off, and has some balls.

I think with some more timing and a different carb, (I agree 100% niceguy) I can get a little more out of it. And, I am having the bottom paint soda blasted, and hopefully that will help a little. Right now it has several cotes of old "shark white" paint on it, and it looks like crap. If I can get 50 MPH out of the small block, I will be happy.

Thanks again for all of the help and advice guys, I appreciate it.

I have the 242 with the BBC and only see 55 gps, so 50 with a sbc should be about right.

Good luck