350 vs. 350 Mag mpi...just swapped...now prop?

justinVIP · 11-13-2003, 08:54 PM

I have a 1995 VIP Victory 2102 w/ a 350 4 barrel 260 HP, 21 pitch Ballistic stainless prop, and I run about 56MPH @4500RPM w/ 2-3 people and 1/2 tank of gas. I want 60+ MPH! The motor in mine is a 2001. I found a 2002 350 MPI(multi port inj.) Mag, that a guy will trade with me. I know him well. He has worked for a boat manufacturer in my home town ever since high school. ('Profile' offshore power boats). He got this motor straight from Mercruiser as a testing motor. He said that it has 60 hrs on it when he hooked it up to his computer. He would swap motors with me for $2000. (He has his own boat repair shop now) He has the motor on a stand so I could here it run. Is this a reasonable deal? Could I gain 5-7 MPH with an extra 40 HP?, or only 2-3? I'm trying to justify this purchase, and sometimes I am very good at justification, if you know what I mean. Bottom line, I have two friends with boats that are very close to beating me, and another just bought a 95 18ft. Crownline with a 305. He will probably beat me unless I do this swap. Can't have that.... Thanks for any and all info. Justin

Update...I bought the 350 mag. now what prop should I try? High 5, Mirage, Ballistic, Laser?????

Mbam · 11-14-2003, 07:27 AM

What's your old prop? Have you run it yet with the new engine?

HOUSTONPROP · 11-14-2003, 08:32 AM

go with a Mirage plus and ,Guess what I have one.

cutom lab finished and the new acclerator blade design that will make it go,if fully Guaranteed,new, and the cost will be at a used one,give me a call, and I will get you dialed in after we talk a bit more,nice boat .

or ,we can change the pitch on the Ballaistic ,it's a good performing prop ,they have alot of rake for lift and are thin which helps 1) saving the outdrive if you hit something hard

and 2) increases the performance like a labbed prop.

justinVIP · 11-14-2003, 08:51 AM

No I have not run it with the new motor yet. We don't have it swapped yet. As soon as I start testing, I will give you a call about the Mirage prop. Thanks for the info, and any more would be welcome. Do you think that 60+MPH is reasonable?

kidrock · 11-14-2003, 11:40 AM

beg, borrow some props start w 21 3 blade. It can get costly if u have to buy.

HOUSTONPROP · 11-14-2003, 11:46 AM

That's right Kidrock.

And at Houston Prop you can try before you buy.

Caincando1 · 11-14-2003, 01:43 PM

40HP really isn't much of an increase. You're looking at 1-2MPH. What is the rev limiter on the 350MAG? I'd try the original prop first, then go from there.

Last year a bunch of us road tripped to Sumner, to take a tour of Profile. Randy is quite a character.

Brian

mopower · 11-14-2003, 08:56 PM

Brian's about right...1 to 2 mph

. You may not even need a prop change , just turn it 200/300 rpms more.
To see 5/7 additional mph you'll probably need 100/150 hp.
A friend of mine went from a 350 mag to a 325hp crate motor and got MAYBE 3mph. Finally went to worked over 406" sbc and saw a total of 10/11 mph over the 350 mag or 68/70 mph. This was a Rinker 209 Captiva...somewhat similar to yours

His boat is the first one going out the dock on the left.

11-14-2003, 11:43 PM

Put a blower on it! Or better yet, figure out how to couple that Firecat engine with it. They have about 100 HP which should get you close. LOL

11-15-2003, 09:01 AM

On a more serious note, what drive and ratio do you have? Your speeds are tough to calculate without that info. I assume you are talking speedo speeds not GPS right?

I would say if you could spin the prop you have close to 5000 RPM with the new engine you will see the speed. The 350 Mag is designed to run @ 5000 where your regular 350 is probably designed to run 45-4600. Try the prop you have and then make a change or have it labbed if you need to tweak it a little.