Top end speed

[thatsmrmastercraft]

Been awful dry for you guys for a while. Unless you are trying to pull a real big guy footing, the 351 with a 13x13 should get the job done. There are enough footers on here that someone will jump in with their set-up. Newer CNC props have a lot to offer over the older props when it comes to footin'.

How about posting some pics of the boat?

[EJ OJPROP]

What is the RPM at 39-40 MPH?

[madcityskier]

How much do you weigh? 42 would be fast for most people.
That's about what we run me at. In all fairness there's not a lot of throttle left over at that point.

[Jim@BAWS]

You should get 45 MPH with a standard 3 blade 13 x 13 at 4400 RPMs.
With the speed you are getting, sounds like your secondaries are not opening.
They should open at 3200 RPMs.

Jim@BAWS

[east tx skier]

When you have your flame arrestor off to check the secondaries, give it a good cleaning. Spray thoroughly from the inside-out with carburetor cleaner (away from all painted objects and loved ones). Air dry thoroughly before reinstalling. The motor needs to breathe.

[maxpower220]

Any chance that you have GPS verified the speedos?

[TRBenj]

I agree that something isnt quite right if youre only getting 39-40mph unloaded. 43-45mph would be more typical of a stock 240hp small block Ford powered boat if the engine is performing properly. Assuming youre not at high altitude, anyways.

Like was asked above, the max RPM youre achieving and more information on your prop would help diagnose the problem. The speed needs to be verified with a GPS as well. Once we confirm you have a real issue, then we can start to investigate why. The 2 most common issues for lower top end are the secondaries not opening all the way (I disagree that they should be opening at 3200rpm though- 3600-4000rpm would be more typical), and final timing being too conservative. 10 initial is fine, but total should be around 35 degrees.

Regardless, I wouldnt expect to do any better than 40-41 with a footer behind the boat with the stock powerplant. Thats with a perfectly running stock engine and a good prop (preferably a modern CNC one). You'll never see 42mph with throttle left over with a footer in tow, unless youre a pretty small statured guy with flat feet!

If youre a big guy, like to foot fast, or need a little extra oomph for 1-foot speeds (I fall into this category) I think youre going to need to start considering engine modifications to get you there. The good news is that the popular GT40p top end package (upgraded heads/cam/intake) will put you in the 325hp range and makes for an awesome package for skiing and footing. My boat will hold 45mph with 1-2 big footers in tow. Going from normal foot speeds (~39mph) to 1-foot speeds is nearly instantaneous.

[kyfooter]

Don't think you're going to get that boat to 47-48. I had an '86 and at 4700-4800 RPM I would top out at 43-44. My 197 also topped out around 44. The only other MC I was in that got near 46 or 47 was a 1995 ProStar with a 1:1 transmission.

Even if you manage to get the boat to around 45 or so, the wake is going to be pretty bad. If footing is your thing, and you need an inboard, look for a Malibu Sportster. You may give up a little quality, but the boat screams and has a very nice wake...very nice (for footing).

If you're a hard-core footer, find a Barefoot Sanger outboard. Best wake for footing of any boat or any engine. The nice thing (other than wake) about the outboard is even at 45 mph, you're only at about 2/3 WOT. The bad thing is the boat isn't that great for much else.

Good luck.

[gid]

Originally Posted by kyfooter

Even if you manage to get the boat to around 45 or so, the wake is going to be pretty bad. If footing is your thing, and you need an inboard, look for a Malibu Sportster. You may give up a little quality, but the boat screams and has a very nice wake...very nice (for footing).

I owned a 1999 Malibu Sportster - great great boat, wish I still had her. It was a hot rod on the water. T

[TRBenj]

Originally Posted by kyfooter

Even if you manage to get the boat to around 45 or so, the wake is going to be pretty bad. If footing is your thing, and you need an inboard, look for a Malibu Sportster. You may give up a little quality, but the boat screams and has a very nice wake...very nice (for footing).

No doubt there are better footing boats out there... but if a few mph is all that separates the guy from enjoying his boat to the fullest, jumping ship to another brand may be a little extreme. $1500 worth of engine upgrades will get him the extra speed he wants. One would assume that the overall ownership experience factored into his purchase originally, and nothing has really changed on that front (in other words, going to a lesser built boat with a better barefoot table may have negative ramifications). The wake and table will be no less lousy at 45mph than they currently are at 39mph.

All this coming from a non-MC owner... but Ive had to answer the brand/speed/wake question before. Very happy with my engine modifications and boat brand of choice!