The V 20 hits 50mph tops, but any faster ?

[nymack66]

Damm,
Ridge if it was not for that cooler of encouragement you loaded up I would have nailed it..Congratulations Capitan and good job Ridge ..

[THEFERMANATOR]

A REV4 shouldn't hurt your holeshot, if anything it will make it stronger. And it would be a much better prop for the lighter weight of the V-20 VS the MIRAGE.

[RidgeRunner]

Originally Posted by THEFERMANATOR

A REV4 shouldn't hurt your holeshot, if anything it will make it stronger. And it would be a much better prop for the lighter weight of the V-20 VS the MIRAGE.

Better holeshot you say, really? It gets up fast now.
What pitch should I try? The 21 Thunderbolt I have now is the Quicksilver clone to the Mirage. I have 11% prop slip when I plug in the numbers. The motor is as high as it needs to be, I can see the water rushing around the lower unit about 1/2" above the stock water pickup and well below the cav/vent plate. I can trim it out without losing bite or water pressure, when over trimmed it throws a nice rooster tail but speed don't come from there. The setup isn't far from optimal now, I am not totally handicapped, I have been rigging boats and prop testing since 1987, I just don't know squat about conversion from 3-blades to 4. Any ideas on how many rpm I will loose going to the 4-blade with the same pitch?

[RidgeRunner]

Originally Posted by nymack66

Damm,
Ridge if it was not for that cooler of encouragement you loaded up I would have nailed it..Congratulations Capitan and good job Ridge ..

You guessed 54, I needed another person in the boat or another giant cooler full of adult beverages... Thanks nymack.

[THEFERMANATOR]

http://www.propgods.com/content/propellers.aspx

I posted this in another thread, but it gives you a general idea of what MERCURY's props do. The MIRAGE is designed for large heavy boats with big HP, the V-20 isn't exactly big and heavy. The REV 4 is designed for lighter boats and top end. The VENSURA is similial, but is basically a 4 bladed MIRAGE.

[spareparts]

if your trying to get the bow to lift, what about a tempest? I've never had much luck with them on boats I've tried them on, but I figure they must work on something otherwise they wouldn't still make them. they have more blade surface than a laser, and seem to work better on heavier boats liek the V(vs a bass boat). As far as four blades, my experiance has been they will lift the stern, pushing the bow down, unless its a high rake fourblade and they generally work better on light boats. If you can't find a 23 Mirage to try, carry your 21 to a prop shop, tell him you need 200 rpms less and soem bow lift, a good shop should be able to dial it in on teh prop you have.

[captpete13]

Thanks Ridge. I would have to say it was nothing more than an educated guess based on the speed of my v with its 225. You can never have too much power. Those 3L Mercs do sound mean don't they. Lots of luck with your new setup.

[RidgeRunner]

Prop Gods recommended a Tempest in a 23p. My prop slip was 14% not 11% as reported. They suggested the Rev-4 was not faster than the Mirage in their experience. Tempest has the same blade design as the Rev-4 just 3-blades with lots of bite. The Tempest turns a few more rpm than the Mirage in the same pitch. Prop is on the way for testing..
Keep you posted.

[THEFERMANATOR]

You may need to raise the engine even more with the TEMPEST from what I've heard about it. It likes to run with a little air in it to help it spin up.