What engine am I working with??
 

Hi, i am going to look at an 04 26' commander signature this weekend and I don't know what engine is in it. It's a 454 but I'm trying to figure out if its the 7.4 or the 454 Magnum, it has aftermarket imco intake manifold so I can't tell. The owner says the boat does 61 and it flys out of the hole, he is in Utah so I guess that makes a differance since he is at 6000 ft elevation, he said it should be faster at the river. If anyone could give me their opinion I would really appreciate it, thanks.

Ask him to give you the block
Casting numbers - that will at least tell you if they started out as magnums.

It's a single engine boat. I'm flying to Utah this weekend to look at it and test drive it so I will try and find the casting numbers then.

If I was flying anywhere I would make them give me the casting numbers ahead of time - but that is just me.

post a pic or the link with the engine in a picture..we can tell from looking at it..

what size prop does it have?

That is a 500efi or AZ Speed and Marine intake and it has Imco exhaust. That is not a stock Merc engine.

First off the bottom intake is red. I would get a pic of the block. If its red also you have a Volvo motor. The intake could have been from a 502. The valve covers look like older merc valve covers. Is it a serpentine motor?

fixx
 

it looks like a nice boat but it may have also had a hot engine in it at one time..that engine looks like a take out from somthing else and like mentioned could be a volvo engine or a varity of something piut together to just sell it..i would make sure you water test it and not for just 5 minutes...i would at leaste burn through a half a tank of fuel to see if the engine is even any good...
just my o2..

Alright just finished driving it and it runs very strong got it to 58 mph but at 5800 rpm, it's got a tiny little prop on it and its only a 19p, I'm thinking it needs a 24p or 26p Bravo 1 prop. The casting # on the block is 10114182.

Casting Number 10114182


Added to Site 2010-12-25 12:43:44 (798 days ago)
Manufacturer Chevrolet
Category Engine Blocks
Type Big Block V8
Date 1991+
Notes 454, 4 bolt, Generation V.
Standard deck

yikes!!
 

i would make him find the rite prop for it...btw you want a rev 4 23 pitch..just because it spins a 19 p prop to 5800 does not mean it will have the low grunt to pull the boat out of the water with a 23 or 24 p prop..could be running on 7 cylinders for all you know..it looks fishy and smells fishy with that prop on their

I forgot to mention I got this 4200 lb deep v boat to 58 mph in Utah (@ 5000 ft above sea level). I can't wait to see what she does in Havasu or the ocean with the correct prop.