Prop SLip

[baywatch]

I was just figuring my prop slip and curious what would be considered a reasonable #. My consistant # is 11% but I did have one pass that It was 9%. However on the faster pass there was a bit of a tail wind and I was using a GPS for top speed reading so that is probably cheating.

The boat is a 36' Apache she is spinning non-labbed 24 pitch 4 blade Bravos on Bravo Drives (1:5's) and WOT is 4900 RPMS @ 66.2mph ( I had one pass at 67.2mph) Engines are 502 mag mpi with 415 HP @ the prop

The boat is heavy as hell (over 10,000 dry) and I realize I am not gonna win any races and average cruise manners are more important than top end. It really responds well with the current set up but I was thinking maybe if I went to labbed props I would maybe gain 100-200 Rpms.

Any thoughts or recommendations.

[baywatch]

Bueller, Bueller? Come on, someone has to have an idea what sort of slip # I should have and whether or not I should be satisfied with my current 11% number.

[QWKRN U]

Im no expert, but I did stay at a holiday Inn Express within the last year.

Id say 11% in a V bottom is very good.Not sure that you will be able to improve on that a whole lot. Labbing the props will net you a 100-150 rpm increase.
Im sure Bret will respond to you after the holiday and he gets a chance to catch up.

[Griff]

Thats a very good number for a heavy V bottom. It probably even a little better. Bravo props are stamped on the heavy side and the props are probably closer to 23-23.5 pitch.

[bbladesprops]

Hi guys.

Yes.

Labbing the props to the correct configuration will help the boat. However, it won't be huge on the top speed numbers. We have to be careful with your hull. In order to make the Lab proces work we will add rake to the props to carry the bow with less trim. Then the Lab must be a little conservative. That means leave the cups high. Your R's are in the right place to gain 100-200 and reap the rewards from Labbing - SMOOTHER and stronger acceleration, and a couple R's with a couple mph to follow. Your slip is low to start and that is in your advantage.