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diligaf
05-24-2001, 06:59 AM
Hello guys, Brand new to REALATIVELY high performance boating. Went froma 3.7L 18 footer to a 96 Baja 232, 7.4 carburated, 300hp bravo 1 drive, and am getting the SPEED itch.. My question is this,,,, How reliable is this motor to begin with ?, how reliable would it be with running less than 5 pounds of boost. I am brand new to this board and in only 5 minutes have seen MORE THAN ENOUGH horror stories about BLOWN UP !! motors. Any advice would be greatly appreciated.... Thanks in advance..

boatnam1
05-24-2001, 08:45 AM
hi,i can tell you from past experience if your going blown you got to get the wallet out.don't listen to the guys telling you if you only run 5 pounds it will be ok.thats not true,im sure there guys out there that have done it and gotten a lot of hours,but on the whole it just won't last.you could run two to three pounds but whats the point.if you do decide to go with the stock motor a least change your valves, head gaskets and put a gaint oil cooler on it.drive it careful on takeoffs and turns and i think it would last a while.i ran a littlefeild blower running 6 pounds on my stock motor and it didn't last long.three of my freinds ran the pro charger on there stock motors and they didn't last very long also.i can tell you one thing for sure when doing motor work i have been to most in so.cal area,and clay smith built me a motor that just wont quit.alot of other places just pull you motor out and send it somewhere,that is not the way to go.good luck and remember once you get your boat to go faster it will be ok for a while then you will be looking again for more speed so build your motor with that in mind,its a lot cheaper that way.

ponponracing
05-24-2001, 09:24 AM
If you want to run 5 pounds of boost, you have to prepare your short block block for the blower application: blower pistons (forged low comp. pistons), balancing, heavy-duty clearances, etc.. You also have to prepare the heads: better valves, better springs, better valve seats, reworked combustion chamber. With a stock piston to start with, the max boost you can run with (almost) no problem is 2-3 pounds. It will give you a fairly good gain from the stock performance. If you want more, you will have to invest in the motor preparation. If the whole thing is not tuned perfectly, I recom-mend running on boost for less than one minute, otherwise you will find out what it cost to foul around with a blower.
Read what boatnam1 mentioned. I know this guy is not exagerating.

time2burn
05-30-2001, 09:38 AM
Been reading this talk and it's pretty good stuff so I thought I would add my experience I've had with my setup. I have a 25' baja outlaw with a 502mag MPI, a Procharger stage 1, after cooler with lightning SS tube headers. At first the set up was way too rich and blackend the back of my boat but after I sent my ECU to Arizona speed and they recalibrated it for me it cleaned right up. I've got over 400 hours on the engine with 120 hrs. at 5 lbs boost and the last 30 hrs. at 7 to 8 lbs. I never use anything less then 93 octane pump gas and if i have any doubt i keep several cans of octane booster. I occasionally blend about half a tank of av gas with pump gas if I'm gona have a wild hair weekend. I try to run just a little on the rich side without blackening the back of my boat. With fuel injection all I have to do is raise or lower the fuel pressure and watch my in dash fuel pressure gage to make sure it stays right. About 40 psi at idle is pretty safe with 55 to 60 psi at WOT. Of coarse I do the WOT then stop and check the spark plug once in a while to varify it. hey but so far it's worked for me cause she's still holding together. I'm getting 84 mph on speedo or 82 on my GPS with a 28 pitch merc. Bravo 4 plade prop. Anyone else with this same set up let me know how many hours you got and how many hours should i go before needing to freshing it up or replace the engine. Hope this helps.
[This message has been edited by time2burn (edited May 30, 2001).]

time2burn
05-30-2001, 01:45 PM
Take warning, I owned a 23 baja Islander with a 502 mag mpi that did 72 mph. And I must say it was all it could handle as it chime walked. It had a v haul that just kinda rounded out at the bottom rather then a sharp v or pad v. It acted as if I was driving a rear wheel drive car on the snow and was trying to take off to fast. Swaying back and forth with the stern wanting to come around. Needless to say when I try to get a High performance mechanic to install a Procharger on it he said "are you crazy, are you trying to get yourself killed". He talked me into a bigger boat 25 foot baja outlaw and I am so glad he did. Fast and safe is the only way to fly. If yours has a pad or sharp point on the bottom keel you might be ok but if it's like mine was rounded don't do it. Just my opinion.

scarab
06-03-2001, 05:13 PM
I'm running a 22ft. Scarab with a 454 lx,330h.p. I was getting 70mph. stock then installed a Whipplecharger and Eddie Marine exhaust. I know get 80mph. on gps. I run a 30 pitch prop to keep the rpms in perspective. I've had it on for 2yrs. and over 200 hrs. without a problem. I drive it alot at cruising speed openning it up when needed. Originally posted by diligaf:
Hello guys, Brand new to REALATIVELY high performance boating. Went froma 3.7L 18 footer to a 96 Baja 232, 7.4 carburated, 300hp bravo 1 drive, and am getting the SPEED itch.. My question is this,,,, How reliable is this motor to begin with ?, how reliable would it be with running less than 5 pounds of boost. I am brand new to this board and in only 5 minutes have seen MORE THAN ENOUGH horror stories about BLOWN UP !! motors. Any advice would be greatly appreciated.... Thanks in advance..

froggystyle
06-05-2001, 12:52 PM
These guys are right on. The real trick, is that if you build the motor right for 5 lbs, meaning a forged crank, rods, blower pistons, valve train,and balance the whole deal, then you can run 10 lbs with no more money spent! Once you roger up the components for a strong bottom end you are home free. I have a 454 with a 8-71 BDS huffer on it, and with nothing really exotic,I am pushing 900 hp and turning 6600 rpms in a 19' Daytona. That's 108 on the GPS for those of you doing the math! The cool thing is I'm still kind-of running pump gas. Without the supercharger, I would have around 500 hp with my heads, carbs and setup. Obviously, all have been dialed in for blower work, but cost per horsepower is about half that of normally aspirated! Have fun with your project.

needforspeed2
06-06-2001, 07:22 PM
Hello i have a 98 240 sport with a stock 330 7.4 that i have installed a 250 power charger with stage 5 dean nickerson carb a set of headers and good fuel system.
The boat had 48 hours on it when i started. it now has 146 hours on it. I'm running 5 pounds of boost and 100hp nitrous plate .. "knock on wood" It's been great .
dean and brad at nickerson performance are very very helpful .. i had a 66 mph boat that now runs 85 mph blowers are great ..

formula93
06-15-2001, 06:35 AM
Procharger works great....less strain on drives than a BDS or Whipple charger. Even tho' both BDS & Whipple are different they are similar to each other and very different from a Procharger. The Rotary type chargers build power more power from bottom thru midrange where the Procharger builds power (boost) more slowly from idle thru your highest rpm. So the stress is not as great out of the hole with Procharger as is a Rotary type. For a copy of the Poker Runs America Supercharger comparison article
email me a fax # to send it to. It cannot be emailed as the graphics make it to large for my server.....so it must be faxed.
gkwright@att.com
I run a Formula 252 with a HP454-450hp baseline engine with 5# boost & a Nickerson Performance modified (flowed) Holley 750/4150. Works great, no problems except the engine is wiolling to go faster than the driver is willing !! (over 75mph gps).
Base line 330hp 454's do not have the internals to stand up to any blower for long. Get a strong block/crank/pistons/rods & then you are as suggested "home free". At this level of boost, very little is to be gained from "headers", so save your money. Do use good (Corsa or other) thru hulls with the stock Mercruiser manifolds and your ok. The difference between 3# & 5# of boost is about $80.00 for a pulley, so go with the 3# first until you are "tested and trained" with the new power. It will surprise you.
Above all....enjoy ! ( & have Dean Nickerson modify your carb! )
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