Prop venting with the 3.0 merc.

[Suprathepeg]

Where you're going to notice the benefit is in prop pitch. So if you're propped for higher speed you'll get hole shot similar to a lower pitched prop. I think this is beneficial to any through hub setup propped for top end performance.

 

[StingRay_90V4]

I am cerently running a 17p. But i have a 19p prop that has a fairly weaker hole shot but gives about 1 ton2 mph faster top speed. Maybe i shoild drill said holes in the 19p prop and see how the hole shot and top speed fairs after wards.

 

[Suprathepeg]

Well, put 3x1/8" holes in the 19p and see how you like it. It only takes 15 minutes with a ruler, punch and a drill.

 

[StingRay_90V4]

I think i will do that this weekend before i raise my motor up one hole on the transum. So start with 1/8th bit? What did younuse for keeping the bit lubed? And ibread in one of your earlier posts that drilling the holes also increased your top speed. But the link you gave me indicates its only meant for the whole shot ? Wha holes did you end up with in the end ?

 

[Suprathepeg]

Yea start with 1/8". If its aluminum and you have a quality bit you won't need lube the aluminum is no match for you. I'm still messing with hole size on my new prop. I ended up with 11/32 on the last prop with good results. For some reason the holes helped reduce prop slip on my boat at speed. I have no idea why.

 

[Suprathepeg]

So got the boat in the water and tried out the quicksilver 14x20p 4 blade prop that I snagged for $70. And... um... wow... tons of chochoo out of the hole, this property really bites the water nice!

Cleanest wake yet, the cavitation plate finally out of of water. And get this... 39mph at WOT! Same top speed!

 

[Suprathepeg]

One negative I guess is that there is a lot more bow rise with this 4blade. It still gets on plane fast but the ass , socks down and then kinda burps up on top.