1998 330 Express Cruiser with 6.2L 350's - Is it enough?

I had the same boat but a 2001 340 Amberjack (some minor differences in the cabin, but the same basic boat. It was powered by 8.1's which compared to older 7.4's had a much better cruising speed/rpm combo. You might want to take a good look at the 6.2 torque curve info to see how much torque it supplies at 3000-3600rpm.

That's the normal cruising rpm for that boat. My Amberjack would run at the following...

2400 rpm 11.5 mph full tabs
2800 rpm 16 mph full tabs
3300 rpm 26 mph no tabs
4500 rpm 38.5 mph no tabs

If the 6.2's don't provide near the same torque, you will have to run at higher rpm's with less aggressive props to achieve the same type of performance.
 
Jimmy Buoy said:
I had the same boat but a 2001 340 Amberjack (some minor differences in the cabin, but the same basic boat. It was powered by 8.1's which compared to older 7.4's had a much better cruising speed/rpm combo. You might want to take a good look at the 6.2 torque curve info to see how much torque it supplies at 3000-3600rpm.

That's the normal cruising rpm for that boat. My Amberjack would run at the following...

2400 rpm 11.5 mph full tabs
2800 rpm 16 mph full tabs
3300 rpm 26 mph no tabs
4500 rpm 38.5 mph no tabs

If the 6.2's don't provide near the same torque, you will have to run at higher rpm's with less aggressive props to achieve the same type of performance.
Click to expand...
Thanks very much. I'll take a look at that. There is also a 7.4 2001 340 AJ I'm interested in NY.
 
Like someone mentioned above it's also about how the weight falls in the boat. It doesn't make a lot of sense on paper, but my 400 with 7.4's performs far better than my 340 ever did with the same motors. The 400 gets on plane quicker, stays on plane slower with less tab. Having more weight forward of the props is a real treat...

This is how my 400 runs on 7.4's. General internet wisdom would tell you a 400 shouldn't even be able to get on-plane without diesels :)

53116472560_d03b0a8468_h.jpg
 
Stee6043 said:
Like someone mentioned above it's also about how the weight falls in the boat. It doesn't make a lot of sense on paper, but my 400 with 7.4's performs far better than my 340 ever did with the same motors. The 400 gets on plane quicker, stays on plane slower with less tab. Having more weight forward of the props is a real treat...

This is how my 400 runs on 7.4's. General internet wisdom would tell you a 400 shouldn't even be able to get on-plane without diesels :)

53116472560_d03b0a8468_h.jpg
Click to expand...
Pretty impressive. It looks like you were running with no fuel!
My 97 330DA with 454s runs 30mph at 3400rpm. But it’s got a 17 degree deadrise hull. Is the 97 400DA also a 17 degree? If so, that helps with speed a lot compared to the 21 degree amberjacks (330 and 340ECs).
To the OP, I would look for a big block version if I were you. The 6.2s are solid motors, but they need rpm to get to their horsepower and torque peaks. Big blocks are the ticket. (Or one of the rare diesel versions would be the bomb)
 
Stee6043 said:
Like someone mentioned above it's also about how the weight falls in the boat. It doesn't make a lot of sense on paper, but my 400 with 7.4's performs far better than my 340 ever did with the same motors. The 400 gets on plane quicker, stays on plane slower with less tab. Having more weight forward of the props is a real treat...

This is how my 400 runs on 7.4's. General internet wisdom would tell you a 400 shouldn't even be able to get on-plane without diesels :)

53116472560_d03b0a8468_h.jpg
Click to expand...
Wow! That's impressive. RPM and GPH are less than conventional wisdom would suggest. The mid hull placement of the engines on the 330 EC/AJ make planning easier from what I read. Less torque and tabs due to weight distribution.
 
Creekwood said:
Pretty impressive. It looks like you were running with no fuel!
My 97 330DA with 454s runs 30mph at 3400rpm. But it’s got a 17 degree deadrise hull. Is the 97 400DA also a 17 degree? If so, that helps with speed a lot compared to the 21 degree amberjacks (330 and 340ECs).
To the OP, I would look for a big block version if I were you. The 6.2s are solid motors, but they need rpm to get to their horsepower and torque peaks. Big blocks are the ticket. (Or one of the rare diesel versions would be the bomb)
Click to expand...
Thanks for the recommendation. I think I agree but do want the small block to be enough. I have not been able to find torque curve info on the 6.2.

Love this forum. I have stalked it for a year and appreciate such great insights.
 
I looked at a 400
Stee6043 said:
Like someone mentioned above it's also about how the weight falls in the boat. It doesn't make a lot of sense on paper, but my 400 with 7.4's performs far better than my 340 ever did with the same motors. The 400 gets on plane quicker, stays on plane slower with less tab. Having more weight forward of the props is a real treat...

This is how my 400 runs on 7.4's. General internet wisdom would tell you a 400 shouldn't even be able to get on-plane without diesels :)

53116472560_d03b0a8468_h.jpg
Click to expand...
I looked at a 400 Dancer years ago but declined due to the fact that it had 7.4 gassers. Many at my marina said "don't buy it - it will be a dog". I passed on the boat without seriously considering it. Mistake in hindsight.

A few years later a friend bought a 43' Wellcraft Portofino with 7.4's and I was surprised at how well the boat performed as well.

Another friend bought a 90's 370 dancer with 7.4's and it performed as well as my 340 Amberjack with 8.1's.

All this makes me think that there's something to 33-34' boats being a bit less efficient than 37-43' that is well propped due to their running length in the water. More roomy to boot!

Something else to consider is that either the 33 Express or its twin the 340 Amberjack is a wider boat at 13'5". That extra width might account for more drag than the other boats mentioned (each with more narrow beams) requiring more uumph to get them moving on the water.
 
Jimmy Buoy said:
I looked at a 400

I looked at a 400 Dancer years ago but declined due to the fact that it had 7.4 gassers. Many at my marina said "don't buy it - it will be a dog". I passed on the boat without seriously considering it. Mistake in hindsight.

A few years later a friend bought a 43' Wellcraft Portofino with 7.4's and I was surprised at how well the boat performed as well.

Another friend bought a 90's 370 dancer with 7.4's and it performed as well as my 340 Amberjack with 8.1's.

All this makes me think that there's something to 33-34' boats being a bit less efficient than 37-43' that is well propped due to their running length in the water. More roomy to boot!

Something else to consider is that either the 33 Express or its twin the 340 Amberjack is a wider boat at 13'5". That extra width might account for more drag than the other boats mentioned (each with more narrow beams) requiring more uumph to get them moving on the water.
Click to expand...
Interesting thought! I do love that wide beam though.
 
I have the 6.2 MPIs (320HP) in my 310 which I know is a slightly lighter boat at 15,000 loaded. It goes like a stabbed rat, hole shot is amazing. Optimal cruise is only 21kts though thanks to the 12' beam and the weight, but they're quite efficient.

An enormous advantage that nobody's mentioned yet of the 6.2s over the 7.4s is the physical size: the engine room is a lot less cramped with small blocks in there. That has huge benefits over a season in that you'll not be put off doing preventive maintenance and you can more easily fix things that do go wrong.

All being good on the sea trial, I'd leap at the boat with newer fuel injected engines in it. Much safer, lighter, and more performant. You trade off some fixability but put good fuel in, stabilize it, make sure the hoses and filters are good, and the nasty gremlins that could cause issues on a fuel injected engine should pass you by (fingers crossed and a slug of whisky for Poseidon.)
 
scrumper said:
I have the 6.2 MPIs (320HP) in my 310 which I know is a slightly lighter boat at 15,000 loaded. It goes like a stabbed rat, hole shot is amazing. Optimal cruise is only 21kts though thanks to the 12' beam and the weight, but they're quite efficient.

An enormous advantage that nobody's mentioned yet of the 6.2s over the 7.4s is the physical size: the engine room is a lot less cramped with small blocks in there. That has huge benefits over a season in that you'll not be put off doing preventive maintenance and you can more easily fix things that do go wrong.

All being good on the sea trial, I'd leap at the boat with newer fuel injected engines in it. Much safer, lighter, and more performant. You trade off some fixability but put good fuel in, stabilize it, make sure the hoses and filters are good, and the nasty gremlins that could cause issues on a fuel injected engine should pass you by (fingers crossed and a slug of whisky for Poseidon.)
Click to expand...
Thanks for the insights. This is a heavy boat probably closer to 18k pounds loaded.
 
Thanks everyone! I just had my offer accepted and will have the boat surveyed next week. Your insights and thoughts were very helpful. I'll post pics when I get some!
 
Pat Mustico said:
Thanks everyone! I just had my offer accepted and will have the boat surveyed next week. Your insights and thoughts were very helpful. I'll post pics when I get some!
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Survey showed water intrusion in the transom! Ugh! There are other issues that are not a big concern to me but the transom is a big one. Further inspection required. I'm hoping it can be repaired and the boat is still worth buying.
 
Pat Mustico said:
Survey showed water intrusion in the transom! Ugh! There are other issues that are not a big concern to me but the transom is a big one. Further inspection required. I'm hoping it can be repaired and the boat is still worth buying.
Click to expand...
This is extremely rare. Maybe it's just an anomaly or someone inexperienced with a moisture reader? I am NOT a pro at using a moisture reader... but I do know that there's more to it than just sticking the reader on the transom and having it tell you a number. For example... was the boat recently taken out of the water? Are there any obvious telltale signs of where water would enter such as improperly sealed holes? Any indications of water seepage on the inside?
 
I agree with Lazy Daze. I would make sure the analysis is correct. But if it is I would run. I've corrected underpowered boats, and I've corrected boats that had moisture issues. While both are doable, I will do neither again intentionally and likely not at all. I can't imagine buying a boat with a high likelihood of both issues. Just not worth the incredible time and expense for either issue, let alone both.
 
Some more detail... a Certified surveyor did the trains then a maintenance guy at the marina checked with a student trader and got the same issue.

The wetness is basically a horizontal line just under the waterline. The POD think is that when they pulled up the fish box and crawled inside there was no excess moisture on the inside. A specialist is checking it out and I should know more in a few days.

On the engines... Sea trial was great. Popped right up with no tabs so the new 6.2. 350hp are plenty of power with tuned, 4 blade props. These are not the 6.2s from the 90s. These are the 2015 designed Mercruiser 6.2s that replaced the 7.4s.

Thanks for all the insights and ideas. I need the advice. The deal is not done yet and I am trying not to get emotionally attached but I do want the boat to work out.
 
keokie said:
I agree with Lazy Daze. I would make sure the analysis is correct. But if it is I would run. I've corrected underpowered boats, and I've corrected boats that had moisture issues. While both are doable, I will do neither again intentionally and likely not at all. I can't imagine buying a boat with a high likelihood of both issues. Just not worth the incredible time and expense for either issue, let alone both.
Click to expand...
Thanks. I am hopeful but not jaded or wearing rose colored glasses.i like the group keeping me in check!
 
Lazy Daze said:
This is extremely rare. Maybe it's just an anomaly or someone inexperienced with a moisture reader? I am NOT a pro at using a moisture reader... but I do know that there's more to it than just sticking the reader on the transom and having it tell you a number. For example... was the boat recently taken out of the water? Are there any obvious telltale signs of where water would enter such as improperly sealed holes? Any indications of water seepage on the inside?
Click to expand...
I took the boat out for the survey. It was out a few months ago for bottom paint and cleaning. Not sure when else.

Pretty comfortable that the readings were right. Not comfortable buying it like this.
 
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