looking for speed

[yoder]

i own a 17' ranger sport R72 with a merc 115/both 1995..i am running a lasser2 22p prop.im running under the 5.4 rpms unless i trim all the way up ,then i get blow out and loose speed..what would be a better prop or should i just have the lasser repitched to 21??

 

[JB]

Re: looking for speed

Moving to Prop forum.

 

[Dhadley]

Re: looking for speed

If you'll post the top accurate speed, top rpm (without venting) and what top rpm you're looking for we'll figure out the slip % and go from there.

 

[Ron G]

Re: looking for speed

How high is your cavation plate from the bottom of the boat now?is it on a jackplate?whats your mph at wot?<br /> sounds like you may be high enough now if your blowing out. Everbody likes to makesure your setup is right before doing prop swapping and they need a good baseline to go by.D your fast this morning cheers.

 

[yoder]

Re: looking for speed

venting?? was i out of line??..top speed from my speed O was 48mph.at 5200 rpms..but not full trim..at full trim i get 5400rpms but i blow out and mph drops to 47,,46..guys are telling me i can get 55mph or better out of that boat..is that true or just bass bull??

 

[yoder]

Re: looking for speed

no jack plate..and im not sure what a cav plate is ..sorry ..wot is 48mph on a speed o..well if i trim all the way it more like 46mph..but i get a cool rooster tail..}

 

[studlymandingo]

Re: looking for speed

The cavitation plate is also sometimes referred to as an anti-ventilation plate. It is where people bolt the "whale tail" hydrofoils on to the outboard.

 

[yoder]

Re: looking for speed

oh ok thanks, nope i dont have a cav plate ..

 

[walleyehed]

Re: looking for speed

Flat area just above the prop...keeps air from entering the prop path, from the surface, commonly refered to as the cavitation plate, it's real name is anti-ventilation plate-AV plate..<br />If you don't have one of these, I'm taking a vacation...

 

[yoder]

Re: looking for speed

lol oppsie thought he said fin..doh??ok cav plate is 2.5" from the bottom of my boat

 

[studlymandingo]

Re: looking for speed

above or below the bottom?

 

[yoder]

Re: looking for speed

above studly..

 

[dpfrost]

Re: looking for speed

looking at where the motor bolts onto the transom there are several different holes you can choose from. There should be about 5 different holes you can choose when mounting the motor. Witch set of holes is your motor bolted to now. If you motor is bolted all the way down you might gain alittle speed by moving motor up a hole or two. But need to be careful not to get it to high. Your in the mid range of where that motor like to run as far as rpms. 22p prop is somewhat of a speed prop for that engine. As far as seeing 55mph it's going to be hard to see those speeds. if you go up in prop size 23p or so you will loose even more rpms then you probablly wouln't gain anything. Do you have a ss or aluminum prop. SS seems to me alittle better on speed

 

[yoder]

Re: looking for speed

prop is lasser2 SS. but it blows out at full trim so will raising the eng up make it blow out more .she is bolted in the second holes from the top..thanks frost

 

[studlymandingo]

Re: looking for speed

Kenny would be the best person to answer this, but if the A-V plate is 2 1/2" above the bottom of the hull, you may be just a little high.

 

[walleyehed]

Re: looking for speed

Studly, thanks for the vote of knowledge...the "Real" prop guru, professor Dhadley is around here somewhere, and when he speaks, listen...pick his brain when ya get the chance.<br />As for the Laser II, is it in like-new condition??? If I had the choice, I'd opt for a higher tech prop that will stay hooked at that heigth. I realize you may not want to go through that type of purchase as well..<br />It sounds a bit strange to be in only the 2nd hole down and be 2-1/2" above bottom with AV plate...does this boat have a stepped transom??? a cut-out at the bottom with your thru-hull fittings???

 

[yoder]

Re: looking for speed

well kenny im a dumb ars when it come to this ,yes it apears to be a steped bottom,im guessing i know what your talking about ,i was not able to trim all they way down to messure because of the ground but it was very close to being trim all the way ,price is not a prob until the wife finds out ...but i am looking into a balistic prop in a 21pitch..realy how i ended up on this site the prices rock..and the tech heads here are the best..thanks for your knowledge...

 

[studlymandingo]

Re: looking for speed

Buy your wife new earrings on the same day you get a new prop. It's all about balance!

 

[sangerwaker]

Re: looking for speed

omek, skip the Ballistic IMO. You can do MUCH better for not much more money. Look at Stiletto or Turbo as a fairly reasonably priced, high performance prop. Who recommended the Ballistic? If it was a prop shop, steer clear of them. If it was another boat owner, I'd guess they have never tried too many props.<br /><br />Dhadley and Walleyehed are set-up gurus. Listen to them. I learn a lot from those two and others just by reading threads here in the prop forum.

 

[MurdockJr1]

Re: looking for speed

You said that the motor is a 1995 Mercury 115.This motor is the 2+2 motor and has a max operating rpm of 4750 to 5250 do not turn it harder unless you want it to come apart. Your speed and rpm sound about right with that 22 pitch prop you may be able to get a few mph more by playing with the set-up but do not go down to a 21 pitch. Just my two cents. Good Luck