TSUNAMI I/O repower

[CRO]

Scott

The 188 HP is a ford base 302ci block V8. The previous owner said that it went OK. The reason I want to go with the lower HP is that my son is mostly going to be using the boat and I don't want it to be to fast! The hull has been hand painted black and we will keep it in Tashmoo. Thanks

[John R]

Chris - if you want to keep it a little meaker, look into the slightly modded 4.3 V6 package. It's already lighter than the 8, it's a common block as it's a chevy 350 missing 2 cylinders, a great motor - I had one from 88-92, and can be easily tweaked to 220HP carbed or stock EFI. With the EFI V-6 you'll get much better fuel economy, less weight in the stern and might not be too much more than the carbed 8... Worth looking into.

Good luck

[Briguy]

The 5.7 260hp motor will probably add substatially to the overall resale value of the boat vs. the 4.3. That 4.3, while a good motor, cannot match the torque of the 5.0 or 5.7 v8. Load that boat up with 80 gal's of fuel,fishing tackle and 4 guys, that thing will be a dog out of the hole. You are talking about 4500 lbs loaded. As for economy, a 5.0 or 5.7 will loaf along at 24kts while the 4.3 will probably buzz at 3800 rpm to maintain that, pushing an obviously smaller prop. If you don't trust your son to drive the boat responsibly, then don't let him use it. Go for the 5.7.

[GetReel]

OK, so here is my 2 cents, Briguy is making the right call here, if you get less than 5.7 you'll never get that bitch out of the hole with a full load, you need the torque from the 5.7 and you then cruise all day at 22-24 kts. with MPI at 3200 and burn 8 GPH...you don't want to under power her. I put in a 454 Vortec and have no regrets

[John R]

I stand corrected [img]images/icons/wink.gif[/img]

My choice - if it were mine with a few $$ to spend - for an I/O would be a fuel infected 350. That 454 would be a couple hundred more pounds in the stern but it would certainly move out. The 4.3 option is purely the low end of the HP ticket out of all these engines. Just my thinking. These guys are right in that a 350 would be the better all around choice....

[Water Rat]

Chris:

I am also a new member to the CS site. This is my first time responding to a question on the forum board - hopefully I have done it correctly (I am semi-literate with computers). First of all, I am amazed at how much information is available on this site - "Trayder" has done an incredible job. To that end, if you have not already, I suggest going back over old posts for additional information.

I am responding to your questions between meetings and am pressed for time right now (though you can see where my priorities are) but felt compelled to since I am the original owner of a 1978 Sceptre, and have repowered once already with a MerCruiser 454/Bravo One package. Will be happy to share my two cents - however, it might be easier by telephone or I will try to e-mail you later. However, one thought now is that I strongly agree that a 350 block/260 hp would be the minimum to go with. My original pwoer was a 305/230 hp and felt it was underpowered. Also, going with a Bravo 1 vs. Alpha has many advantages. Good luck and feel free to pick my brain further.

[bobfish21]

Chris,
I have the boat your'e thinking of building and the 350 efi motor is a better choice.Mine cruises 22-24 kts at 7.5-8 gph;avery comfortable and safe speed.These boats actually ride better at higher speeds-when i occasionally push it up to 4600 rpms(just for a mnute or two) the boat seems to benefit from the increased air the hull traps between deadrises,runs38kts top end.Youll be very happy with its cruising speed performance.If I had to do itb again, I mightb opt for the bravo lll duoprop-no torque steer,slightly better numbers at cruise,more control in reverse.Also ,ive been told with a bravo you can run a raw water pickup and sea strainer setup with the motor's water pump handling cooling chores rather than the outdrive-a big help if ,like here on the great south bay,eel grass and plastic bags wrapped around your lower unit can really ruin your day!

[Serenity]

I have a 4.3 Volvo D/P on a 20 cutty which is a lot for the boat. Others I know with the same on a 23 have made comments that they wished they went bigger. Adequate but when heavily loaded, they wish they had more power/speed.

You might want to look into getting a heat exchanger (fresh water cooling system) on your motor. This may be a little costly but I found that this keeps the motor in good condition running antifreeze and with about 1,500 hrs, have not have any major problem yet....knock on wood!... .

Good luck on your rebuild!

[CRO]

Thanks everybody for all the input. I think at this point money is going to be what determines what motor I buy. I think I will stick whit the alpha drive because that is what was in there and I have another boat whith that same unit. I am glad to here that people are getting over 3 MPG out of this boat since gas here is over $2 a gallon and climbing. Thanks.

[Miles Offshore]

Place down here called affordable marine that is very cheap on brand new moters , long block, short block , turn key, whatever. Not sure he ships but he probably would. I bought my long block PCM 350/280 from him for 2300. 5 years ago and still kicking strong. i did go with freshwater cooling as well.If Anyone wants the phone number I will post it.

By the way,dont want to offend anyone and if I do I apologise but I never heard of a place called "Gay Head"? I will leave it alone.