Re-power from 5.7 to 460 worth it?

[Knight1396]

I have an 88 bayliner 2655 with a 260 hp 5.7
Anyone think it would be worth doing a repower to a 460?
Will this motor make much of a difference - speed, power to plane etc?
I understand I would need to replace outdrive as well.
Just looking for some thoughts on this
Thanks!

 

[NYBo]

Re: Re-power from 5.7 to 460 worth it?

Yes, it would make a significant difference, but you're talking big bucks. Only you can decide if it's worth it. In the end, you will still have a 23-year-old boat.

Are you dissatisfied with the boat's current performance? Perhaps a change of prop, trim tabs, etc. could make things more acceptable. I would also recommend a dual-prop outdrive, but that's problematic if you have the original OMC Cobra.

 

[Knight1396]

Re: Re-power from 5.7 to 460 worth it?

Thanks for the input!
I was able to buy this boat at a good price. I have a survey here that has nothing but positive conclusions and values the boat much higher than I paid for it. I understand a boat is only worth what someone is willing to pay for it however.
I dont plan on selling this boat anytime soon and I look at it as a family investment. I am not much into the newer Bayliners as they dont have as much room as this boat does in the same LOA for some reason. And moving up from there, is entirely out of the range of my financial commitment to boating. If I was to invest another 5 grand into this boat I would still have under the average of what these boats are going for invested.

The performance difference is what I was looking at overall. Is there a big difference between the two on a boat this size? enough to make it worthwhile? An icrease of getting out of the water an on plane faster and 8 mph or more would be worth it to me.
Same time up and 3 or 4 mph increase probably not worth it.

 

[NYBo]

Re: Re-power from 5.7 to 460 worth it?

I have to agree with you regarding the amount of room. But there is a simple explanation: In '88, the swim platform was bolted on and therefore not included int he LOA figure. Swim platforms that are part of the hull are counted in the LOA.

What kind of performance are you currently getting? Are you able to reach maximum engine RPM at WOT with your current setup? I'm not sure you'll get an 8 MPH top speed increase over a properly setup and running 5.7. That takes a lot of extra horsepower. If your 5.7 is tired, you may be able to drop in a 6.2L replacement that will get you most of the performance increase of a big block without having to replace the outdrive (assuming your outdrive is in good shape). One more point: the 460 is a Ford motor, which I don't believe has been used in marine applications for years. I believe the manifolds and risers are very hard to find, and very expensive. Stick with the GM-based 7.4 L (454) or 8.1L if you decide to go with a big block repower. These will mate to modern outdrives. You absolutely don't want an OMC King Cobra outdrive.

 

[Knight1396]

Re: Re-power from 5.7 to 460 worth it?

Thanks again!
The outdrive is a cobra. The 6.2 you mentioned, will it match up to the cobra drive?
Do you have any links online to the motor you are talking about? I would love to take a look at this option.
Thanks!

 

[NYBo]

Re: Re-power from 5.7 to 460 worth it?

The 6.2 is a GM small block, but we are getting out my area of expertise. Try posting your question over in the I/O section for better information.

 

[jason32038]

Re: Re-power from 5.7 to 460 worth it?

You could squeeze a good amount of power out of it if you get a new performance camshaft. They don't really cost that much either. I wouldn't swap engine that will just add a lot of weight.

 

[4runneradam]

Re: Re-power from 5.7 to 460 worth it?

Slap some vortec heads on that small block, and a camshaft. That will wake it up!

A Ford 460 is a low reving, low HP, high torque truck motor. If anything, it will slow your boat down compared to a 350. It would have more pulling power though.

 

[QC]

Re: Re-power from 5.7 to 460 worth it?

The last two posts ar pretty confused . . .

1) Cam upgrades are particularly risky in a marine engine. Before you do anything with cams search in the I/O section under "reversion". This is a significant issue!

2) Marine engines are "low revving" due to item #1. So are truck motors (engines) for a different reason; startability. More "pulling power" equals more horsepower which equals more speed. This is almost always true despite our misunderstandings of the differences between torque and horsepower and their relative benefits

3) Ford marine engines are somewhat hard to get parts for . . . definitely harder than GM.

4) Threads like this are best served in the I/O section. This is not a boat specific topic, it is more an I/O topic and would get the best answers over there if anyone is still monitoring.