new guy prop?
 

so im new to the "speed boating" just got a 220sx stingray with a 350mag and a brvo1 with a 21 pitch prop on it....

now the ? i have is the boat will do around 68 mph.. can it go faster with a diff prop or do i have to go into the motor with a 383 or such? any help would be thankful...the reason is i got this one guy on the lake with a crowline that out does me all the time.. lol

thanks

What RPM are you turning and is that GPS Speed?

5000 or somewhat...and yes GPS speed.... now i just got the boat and could not get a great run this weekend but im going up to my other lake house this weekend and going to see what i can do there.....

Not sure what the max RPM is on a 350 mag, but if you rally are turning 5000, ya can probably turn a 23, will it be faster? Dont know 'til ya try.

ok so as i said im new..lol....the higher the number on the prop the harder it will be for a motor to turn but the faster the boat should go? i will have a loss of RPM but a gain of speed..

thanks for the help

Thoeretically you are correct, there are other factors, such as prop design, and diameter. Which 21 are you running now?

Ok....I'll be the one to say it.....I can't believe 68 MPH. :boat:

Me either, that is why I asked if it was GPS. Lets get the details, maybe he has the magical "negative slip" I have heard about many times before:grinser010:

I just looked up all the articles on it.....says it came with an alpha drive, and topped out at around 60 mph. They had a merc racing scorpion motor in a test boat that ran 69 mph. If he does have a bravo...I'd say that would take a little more hp to turn....meaning slower than he thinks. Maybe that's why the guy with the Crownline is spanking him...lol. Still a nice boat tho. :drink:

ok so like i said im new to the speed on water thing...iv got a very good friend of mine that races with a 40ft nortech and he was saying the boat should have not problum doing the 65 plus...and from what your saying is that there is no way it would go that fast??? just trying to see what i got....get my feet wet so to say then get a bigger boat in 2011...

thanks

Not saying it is impossible(well, actually I am), but 65 is only 2% slip, 68MPh would negative -3% which IS impossible, so was that 68MPH measured on GPS or not, we need the whole story in order to help, and the ACTUAL RPM while running that speed in order to calculate what is best for you.

ok ill get a better reading this weekend so dont start a he said she said match.. but it was on gps and i could be wrong..i the boat is new to me and i was riding with the seller with the gps, so i will do it at the lake this weekend.....and maybe a video, then u can tell me what u think would work.

thanks..

just looked to make sure.. the boat has a bravo 1 out drive with a mirage plus 21p prop. just more info.. does anyone know how much hp that outdrive will handle?

thanks

OK, just making sure all is actual, not presumed. The Bravo drive will handle anything a small block can throw at it, especially in a small boat like yours.

would it be hard to put twin turbos on the 350 and forged it..or would i be better off going more cubes?

or i do have a new 6.2 ls3 motor..would it be hard to put that on the boat or would i have to change the computer on the boat? sorry fot all the ?

I believe both of those options would be too much work for that boat, but to each his own. I believe the mag motor may be forged already, but twin turbo's is a lot of $$ unless you are up for it, not sure what it would take to use the 6.2. There are other options also, such as build up the 350, maybe a supercharger.

i got ya...thougt about taking that 350 block and making it a 383... is the 350 mpi the same has a car motor? like heads and intake and such..cam upgrades?? i have not had anyone that can give me a str8 answer...lol

thanks

You stated in your post earlier that you were gonna buy a bigger boat next year. Your best bet (money and problem wise) is to leave that boat alone. It sounds like it runs great now, so just enjoy it the way it is. You'll end up putting alot of money into it, breaking parts, and possibly being down for the season. Your trying to put a 900HP motor in a Chevette. Boats like that can only handle a certain amount of power, then they start chine walking at speeds, cause more trouble than they are worth, and if you have a family, they wont enjoy it. Get a larger boat that is more capable of handling what your trying to accomplish. Until then...leave this fun, family oriented boat alone...lol. :drink:

Sage advice. I've seen many, many people - in search of speed - get downright silly with motor mods. The they find out the outdrive won't handle the power. Next, they upgrade the outdrive - only to find out the hull just wasn't cut out for it. Finally, they find out that their boat was worth twice as much stock as it is now with thousands of dollars in mods that nobody (with any sense) is willing to pay for. Don't join that club. People have literally died doing it.

i know where your coming from...im going to keep this boat as it is....i just have a hard time doing so with whatever i get my mind on...alll ready looking a some boats....talking to sunstaition all week about somthing bigger....

but thanks for all the help...

Great advice. If you just got this boat, you havent learned to drive this boat to its potential yet! And your trying to make it faster? Being a first boat owner, be careful. Boats handle ALOT differently than cars and you really should get some seat time before thinking about a high performance boat. Dont mean to be a downer, but speed kills. Take your time and be smart.

thanks..and i will..i do have other boats just not a boat like this that all im looking for is a lil speed and good ride...but im going to keep this one like it is may play a lil with it..but as u say learn to drive it. and as soon has my other car sells im going to get in a bigger boat...iv road a few nortech boats and but i love the sunsation boats...looking at a 32ssr.. any of you like these boats as well?