Bama

I know a 525 will fit, it has been done, and you are right there is not much room.

Stock low hours is what I was looking for when I bought the boat. A drop in blue motor is most likely the rout I am going.

A buddy of mine bought a boat with a built 502 blower motor. He burned a hole in a piston after 2 days running. I helped him pull the motor, build it, put it back in, then the drive broke. Motor back out for coupler and built up drive from American Drive Service (X mod II). Running strong

The drive is my concern with more power than a stock 525 drop in.

carcommander

Fountain does a pretty good job engineering these things. I would not put a 525 in without going to the XR drive. Otherwise you get a boat that may not work when you want it to.

4bus

iTrader: (4)

I believe the bravo 1x has the stronger upper tower doesn't it?

I would keep what you have in the upper, but do the 1 1/4 lower shaft and bearing housing from an xr. It's an easy swap, all the bravos use the same gears in the lower.

In a boat your size, I don't think you are gonna have issues with a 525 and that drive. Try to plane easy, and if it's super rough do your best to keep the boat in the water.

ealesh33

iTrader: (1)

I have the 525sc in my 27 fever, boat was special ordered with it so came with it from the factory. there is just a small square cut in the back seat for the snout so it doesn't hit, simple actually. A 525sc with compression bump (flat top pistons takes it to about 8.2-8.5:1) and roller cam conversion puts out about 625hp and is a fantastic, extremely reliable motor. Mine is all stock except I have the one step smaller pulley to increase boost a little, and with it I see 7-7.5lbs of boost. Boat has done a best of 80.9mph gps and was rock solid stability wise. I am probably right around the 565hp mark, but I want to do the compression bump and roller cam conversion to get to right around 650hp. I have a bravo 1 upper with an XR lower, and a labbed 26p LH hydro (diameter is cut down to 15", and leading edges of blades are sharpened).

Bama

ealesh33, right around 80mph is where I would like to be. A 525 is sounding better all the time.

The cut out in the seat you are talking about is the bulkhead in front of the motor?

ealesh33

iTrader: (1)

Yes, the seat back goes over this so it can't be seen from the cockpit obviously. Makes it real easy to undo 8 nuts to pull the seat back off and do pulley and belt changes for the blower. You won't see a consistent 80mph with a 525. I got that speed in almost perfect conditions, cool temp, and light load. I have been seeing 75-78 consistently ranging from 2-4 people in the boat, and 1/2 to a full tank of fuel.

4bus

iTrader: (4)

All this time I thought you were talking about a 525efi. 600+hp in front of a bravo is going be tough, make sure you buy some drive tools

Ealesh- are you running a chiller? 7lbs of boost at that compression ratio is just living on borrowed time IMO. It may be working for you, but it is definitely not a set up for a novice.

There is a used 600 sc for sale in the classifieds. Larger displacement, larger blower, twin carbs, and conservative turn key blower power at low boost would prob be a safer set up than spinning a little 177 blower at 12,000 rpm all day. Those little heat pumps scare me

ealesh33

iTrader: (1)

Compession ratio is retarded conservative on a 525sc at 7.5:1, 7psi is no problem at all on that. You don't want to spin much more then 7psi as you start to approach that 13,000-13,500rpm limit of the blower and overdrive it.

carcommander

I don't know what year you have but my 05' is probably worth 40K. Used motor and drive 28k installed. (I priced it) Sell your motor and drive maybe 8K. 20K add and you probably should freshen up what ever you buy while you are at it say 3K. does it need new headers? another 3K. So 23K to 26K, now 63K or so in a boat worth maybe 45K. Most people would just buy a '29 about 60K. I realize you can't do a '29.

If you don't mind spending the 18K to 20K it's cool. ( I have looked at all of this). All of this to get an engine that is less reliable than the HO. Read up on the issues with the 525, valve springs, headers leaking, etc. I could not get it to make sense to me. I can afford the 20K.

In my case I am the only one who likes over 50mph anyway.

carcommander

Pier 57 (no affiliation) has an 05 with a 525 in it for 45,000 listed on their website. You could buy that boat and sell yours far cheaper than you could do it yourself. It also gives you an idea of what your boat would be worth after the mod.