Engine swap.

[chambers1517]

 

[chambers1517]

I did an LS3 swap on my jeep and I am now considering doing the same to my boat. I would gain 130hp, more torque and it is about 200lbs lighter. The boat is immaculate. What would such a swap do to the value. If I get a new LS3 from GM it serves it would be a plus.

 

[dubs283]

6.2 L won't have the low end torque the current 454 (if the sticker is accurate) has

Mariah makes heavy, solid hulls. You'll only note a positive difference with more displacement. 496 might improve performance but imo that'd be a downgrade in engine compared to a 454.

If you have the time/money a 502 with a charger would help a bit. After that the only limit is your pocketbook. The Mariah hull will offer limited returns on investment at that point

 

[chambers1517]

6.2 L won't have the low end torque the current 454 (if the sticker is accurate) has

Mariah makes heavy, solid hulls. You'll only note a positive difference with more displacement. 496 might improve performance but imo that'd be a downgrade in engine compared to a 454.

If you have the time/money a 502 with a charger would help a bit. After that the only limit is your pocketbook. The Mariah hull will offer limited returns on investment at that point

It does have a 454 but it's a heavy engine.

 

[dubs283]

The boat's value is top dollar rn. It's clean and topside sells way more than below deck

Engine/drive upgrades have value to the person performing the mod and a select market. Mariah isn't a performance manufacturer so the market is limited. Do what you like but don't expect a return on investment

 

[matt167]

You need to buy the LS3 and then all the parts to marinize it and probably use a marine cam. Crusader does use LS engines… I looked into it briefly as I have a 4.8L sitting around but the $400 4.8 would cost me about $4000 to make it run

 

[Scott Danforth]

It does have a 454 but it's a heavy engine.

A change to aluminum exhaust manifolds like something from stainless exhaust will drop almost 80#

An iron short block LS motor is about 130# lighter than the BBC. Put aluminum heads on and add a heat exchanger and you drop 60#-70#

What would such a swap do to the value. If I get a new LS3 from GM it serves it would be a plus.

It will drop the value. Because Mercruiser does not use LS or LT series motors. So the next buyer has to be a gear head to appreciate any perceived value. But that value will only be about $2k at most (assuming you do not use the boat after the swap). No where the expense you will insure doing a proper marinization of an LS

If you want to do it for your self, that is one thing. If you want to do this thinking the next guy will pay enough to recover your costs ..... Won't happen

I would gain 130hp, more torque

Some mild head work, a cam change, and good flowing exhaust and that 7.4 liter will have more torque than the LS

Remember, you can not run street cams with wet boat exhaust. So any published HP/Torque gets adjusted down for a cam with no overlap and wet exhaust

 

[chambers1517]

A change to aluminum exhaust manifolds like something from stainless exhaust will drop almost 80#

An iron short block LS motor is about 130# lighter than the BBC. Put aluminum heads on and add a heat exchanger and you drop 60#-70#


It will drop the value. Because Mercruiser does not use LS or LT series motors. So the next buyer has to be a gear head to appreciate any perceived value. But that value will only be about $2k at most (assuming you do not use the boat after the swap). No where the expense you will insure doing a proper marinization of an LS

If you want to do it for your self, that is one thing. If you want to do this thinking the next guy will pay enough to recover your costs ..... Won't happen


Some mild head work, a cam change, and good flowing exhaust and that 7.4 liter will have more torque than the LS

Remember, you can not run street cams with wet boat exhaust. So any published HP/Torque gets adjusted down for a cam with no overlap and wet exhaust

Good point.

 

[dubs283]

Good point.

But the manufacturer specs for the given application are moot?

This a situation similar to rolling into a hot rod convention with a suped up cadillac. Yep, it's cool......for you