96 Rinker 232 Engine Swap
 

I own a 96 Rinker 232 Captiva cuddy that is completely stock with a 7.4L and bravo one setup. I am showing 57-58mph at 4,300RPM with a 21p prop. The engine hours are in the high 400s. Like most people, I want to go faster, but not lose all reliability.

Based on the engine hours, it is getting to the time for a rebuild. My question is, should I rebuild the 454 and beef up the internals to give me the 400-450hp i'm looking for or just trade it in for a relatively stock 496HO/502? I'm not real high on adding a procharger or whipple charger as this decreases reliability considerably (and would never do this to a stock 454/496/502 anyways).

Subsequent questions based on your suggestion above would be: Will the 496HO or 502 bolt right into the current setup? What changes will have to be made? Has anyone done something like this before?

Thanks!

400 hours on a stock 454 is not even close to time for a rebuild unless it has been abused and not had regualer fluid changes... There are plenty of guys running these well over 1000 hrs. The hull you have is not really made to go much faster. You will spend a lot of money trying to get a few MPH out of that boat. You would be better off running the boat as is or sell it and buy something more performance oriented with a 496 already installed. I will be putting my 03 Velocity up for sale soon. It will require nothing and runs in the 70s with a stock 496 mag...... A Captiva with a 496 might see mid 60s, but that hull would probably be a handful at those speeds.... A turn key 496 w/wire harness, PCM, etc is probably going to run you close to $10k (or more) used......

Going from your 7.4 to a 502 mpi would be a simple swap. That being said, IMO, it's a waste of $$$. At most you would see a 5mph gain.

It is hard to justify selling a paid off boat for a down payment on a newer one and have payments again especially for a modest 10-15mph gain. If I was going to make a move, to justify payments I'd need a boat that could consistently see 85+ (I'm sure that would get old after a while and I would want more).

I understand the design and "v" degree is different in a Rinker compared to a Baja and other performance models, but why wouldn't I get the round figure 1mph for every 10hp added? Most older Baja's (90s to early 2000s) with the 454 will only run around 60mph. I almost see that now in my setup. Don't take my response as disrespect or doubting your knowledge.

I would not rebuild until you wear out the first engine.

You are realistically in a 49-52 mph boat as the speed you gave results in negative slip numbers. If you want more speed now then you could rebuild. It won't be cheap. Go with the biggest cubes and HP you can afford. Whether the hull could handle the extra speed has yet to be determined.

Maybe the RPM was between 4600-4800. Would that make more sense???

Figure more like 20 h.p. per 1 m.p.h. increase. So you are probably at about 330 h.p. now. You could add another 80 h.p. with the Bravo 1 without issues as they put them behind 502s (I believe 415 h.p.). Heads, intake, cam, carb, gaskets, labor... Probably 5k in parts and you still are running on a "cast" lower-end. My experience says maybe 5 m.p.h. for your troubles. IMO have your prop "labbed" by one of the supporting vendors on this site and call it a day.

Simply put, it will cost a whole lot more to make your current boat go 65-70 than it would be to buy a better hull with less power and run in the 70s-80s. Your hull is not designed to go terribly fast. In addition to that it isn't designed to handle the rough like a true performance boat is. So figure you will need a ton of horsepower to get the boat into the mid to low 70s. Then your looking at really stressing your drive plus with that hull anything over mid 60s you will need to go full hyd. steering as that boat won't be as stable as other performance boats will be (any boat running over 70 should run full hyd steering anyway). So you are looking at $2500 for steering, and probably at least $10k for a decent motor build. Probably much more (fortunately I haven't had to have one built yet so I am taking a pure guess). Then drive repair if/when it needs it. Plus having to buy a new prop once you add more power. Figure all in all around at least $15k to get your current boat in the mid to high 60s.... There are plenty of 70-80 mph boats in the $20k range (older). So not knowing the condition of your current boat, you should be able to sell it at a decent price if in good shape. Plus resale of a rinker with a ton of power would probably be less than with stock power and much harder to sell as the people in the market for that type of boat don't want that kind of power.

If you have the $$ to throw at it, you would be better off taking that money and buying something better suited to do what you want.

Think of it this way. Take a 600 hp motor and throw it in a pick up truck then add a 4 link suspension, lower it, etc, now take a Camaro or Mustang with 400hp. The Mustang or Camaro with a lot less power and money will out perform the Pick up truck and do it more reliably...

Spending 8k on an engine swap for a boat that is worth 12-14k does not make sense. You will never get that money back if you sell it.

A 1 mph gain takes more like 15 hp.

Well it's all what you want if you plan to keep it for a while put the power you want in it it's not a race hull but it will run strong. You can repower the boat back to the way it was if you sell it and then you will have a higher power motor for the new boat that don't have higher power. yes you will send big cash for the power

I have a 1992 236 Rinker it is a diffrent hull they where more a sport power boat hull that will run with any boat that size they came a 435 hp 502 that ran 70 stock like the stingray Baja boats
I'm running a 502 625hp 28 pitch bravo 1.5 ratio and will run 87 mph @5200 rpm 5% slip and will run 92 mph with a 30 pitch bravo and it runs very stable at thoses speeds the hull is in the water that helps I run the detroit river and alot of lake Erie all summer log.
check out my link
http://www.youtube.com/watch?v=0Edrq...hannel&list=UL

I tend to agree with what everyone says here, I ignored it on my boat, and built my 502. Difference being I already had the 502 stock. I will tell you I've humbled more than a few "fast" boats this year (a 70mph boat is fast everywhere but on this site!!!) But starting with a 7.4 you will be in some big money to get to 450-500hp. You would be better off swapping in a complete motor.

I know zero about your hull, but everyone warned me about chine walk etc etc etc, things runs straight and stable to over 70. That being said, I'd have a 75-80mph boat with a faster hull in its size (221 Liberator), but as noted in this thread...it's paid for, and that's something. And it's great in the water I boat in for it's size.

Hey Low-psi, you gonna be out anymore this year?

I've never seen you out there, but a 90mph rinker!?!?!? That's pretty awesome!

Hope to be out on Sunday and planing a trip to PIB next Saturday the 22nd. As long as the weather holds out and I don't hit anything else I hope to be boating into October.........

a little info that might help you think some things through, i also do not know much about your boat persoanl, but i do know some about motors. I own an auto repair and custom car build shop. We build alot of what i will call mid level bbc. I have a company that sell a stroker kit for the bbc. at .060 you will have a 496 and at .100 you will have a 505. this kit comes with scat crank,scat forged h bean rods with full floating pins, rods ar 6.325 i beleive, rods that have been clearanced some to help reduce the clearancing needed in the block, forged ross piston that are +18cc, rings, bearing,flex plate, dampner and balanced.

When assemblied into a stk deack block your piston will be .010 in the hole and with 121 cc heads you will have 10:1 with a .040 gasket. For a boat i would look to put a .100 gasket in and bring the ratio down closer to 9.5:1 and if you dont go crazy witht the timing you will be good on pump gas.

i have one of these kits together in a drag car th at we used 11occ heads and thin gaskets to put it close rto 11.25 if i recall the number, dyno out about 650 with al heads and thats before the 250 hp spray kit. motor has been together for 5 years now without the valve cover ever being cracked he is turning almost 7000 and races every weekend. so i would feel good with these parts living at 5000 as we all run in the boats for long time duration.

kit runs 1995 unbalanced, no flex plate how you would need it should be about 1750. you would still have to get it balnced with your marine flywheel( much heavier than an auto flex plate ) at your machine shop when they do the final block clearnacing. alot of times you can find another454 block from between 250-500 this would allow you to recover some cost by selling your motor as running used motor with documented hours.

if you would like some more info just pm and i will get it to you.

you would have about 750-1000 in machine work at a shop, and then all you need is a set of heads, i would guess you would not want use the peanut port heads on a motor like this

Right on, I'm out of town until Monday night, then hope to be back on the water that same weekend, maybe I'll see you around. I also have the same plan, to boat into October as always...weather dependent of course.

I hadn't heard/saw that you hit something, there has been a lot of that this year with the water being so low!

http://www.offshoreonly.com/forums/g...y-weekend.html

Still limping along on bent prop shaft and garage repaired prop.....

Sorry for the hi-jack.

So was that you today? Teal Liberator. Fastest Rinker I've seen.

I'm thinking of replacing the weak 5.0MPI with a 496 in a 2004 Rinker 232 if it will fit. I don't know if the geometry has changed since adding the walk-thru from the earlier 232s that had 454's I am definitely going to repower but I would go big block if it would fit. Otherwise it will be a small block 6.2. I'm not looking to go 70mph but 55 would be fine with me.

My '99 232 Rinker would run 52 MPH GPS with a stock 5.7EFI (260 HP). Same hull as your 2004. The walk-thru may make it tough to access the port side of the motor on a 496 swap. A 6.2 will get you to 55 MPH.