underpowered and frustrated - v2.0

Four Suns

Four Suns

Not a pot stirrer
TECHNICAL Contributor
Oct 4, 2006
10,533
Williamsburg, VA
Boat Info
2003 480 DB
Engines
QSM-11 Diesels
My 480 DB with QSM-11 diesels will only go 35 mph at 2300 RPMs and the engines are screaming. I'm coming from a 20 foot jet boat and my jet ski and jet dinghy all go faster so I find this performance unacceptable. Sea Ray is no help. They won't return my call. I am more frustrated than a 35 year old nerd living in my parent's basement who hasn't been laid in.. well.. ever. I feel with near 1400 HP, I should be able to go faster than my Chevette which only has 65 HP. Any suggestions? Should I write a letter to Brunswick? Maybe I should put some 32 blade props with more bite on the boat? Someone "in the know" told me I should have gotten the smaller QSB 380 HP engines as I can run them at 8000 RPMs all day.
 
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Four Suns said:
My 480 DB with QSM-11 diesels will only go 35 mph at 2300 RPMs and the engines are screaming. I'm coming from a 20 foot jet boat and my jet ski and jet dinghy all go faster so I find this performance unacceptable. Sea Ray is no help. They won't return my call. I am more frustrated than a 35 year old nerd living in my parent's basement who hasn't been laid in.. well.. ever. I feel with near 1400 HP, I should be able to go faster than my Chevette which only has 65 HP. Any suggestions? Should I write a letter to Brunswick? Maybe I should put some 32 blade props with more bite on the boat? Someone "in the know" told me I should have gotten the smaller QSB 380 HP engines as I can run them at 8000 RPMs all day.
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Well.... Someone in the know (that's a pretty weird saying if you break it down....) told be that if you spend somewhere between $25,000 and $125,000 you might be able to get 'er up to 38 or 39. But you would have to tilt that antenna back to improve the aerodynamics.
 
I consulted with a non-winged cool mod specialist and he suggests you change your spark plugs and clean the flame arrestor in place, without removing it, by spraying carburetor cleaner directly at your flame arrestors.

After you try this please give up a performance update.
 
Is your bottom clean? You may have to use a wash rag after a wot ride in that Chevette!
 
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I suggest upgrading to gas stern drives, they are much more reliable and if you flush them often they will last a long time...
 
One of the guys on my dock said I should use gasoline instead of diesel. He says the high compression and double octane will give me over 2800 HP. He says Sea Ray is in a crooked deal with Cummins and they don't want us to know the real potential of these engines because we could buy cheaper engines. The dock guy is going to bring his drill an tap tools to put some spark plugs in. We'll get the ignition system from a 1972 Plymouth Scamp he has in his yard.

I can't believe Sea Ray didn't do this. Booo on them.
 
You need to rub oil over the bottom of your hull. Preferably Synthetic.
 
Install a 500 gallon tank to hold liquid nitrous oxide and have at it. Feed liquid N2O directly to the intake behind the intercooler. It'll cool the charge and raise the oxygen level.
 
My bet is on that big ass heavy grill he hauls around to burn the outside of his steaks.
 
You should buy a Marlow, it is a much faster boat. I hear they have surface drives on those things.
 
Gary - Here's the answer:

Two GE T-58 gas turbines.

The compressor has 10 stages with variable inlet guide vanes and variable stators on the first three stages. The compression ratio is 8.4:1, it flows approximately 13.7 lb/s (11,000 cfm) @ 27,300 rpm. The combustion chamber is of the annular design. Two turbines drive the compressor and one drives the load through the rear at 20,500 rpm. Specific fuel consumption is 0.64 lb/shp/h. The engine weighs 350 lb [159 kg] and produces approximately 1,400 hp. With a 3.25:1 reduction gearbox this engine will produce 1,270 lb-ft of torque at 6,000 rpm. It will burn diesel, so no conversion problems there. Couple them to arneson surface drives and you've got your problem solved.

The only downside is you may have to convert your 3 staterooms to fuel tanks. 3000 gallons ought to do it...

If you do the conversion correctly, you can use the 700 degree exhaust as a grill...think of the weight savings there...and now you have 2800 HP - and Frank - he won't need nitro!
 
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You should repower with outboards. :lol::lol: Don't you even have a picture of your boat with outboards?
 
Four Suns said:
My 480 DB with QSM-11 diesels will only go 35 mph at 2300 RPMs and the engines are screaming. I'm coming from a 20 foot jet boat and my jet ski and jet dinghy all go faster so I find this performance unacceptable. Sea Ray is no help. They won't return my call. I am more frustrated than a 35 year old nerd living in my parent's basement who hasn't been laid in.. well.. ever. I feel with near 1400 HP, I should be able to go faster than my Chevette which only has 65 HP. Any suggestions? Should I write a letter to Brunswick? Maybe I should put some 32 blade props with more bite on the boat? Someone "in the know" told me I should have gotten the smaller QSB 380 HP engines as I can run them at 8000 RPMs all day.
Click to expand...
If you want to go faster get a different boat ya fcking idiot. Hey, this is fun. Where's wingy I want to pick on him.
 
Remove the bridge, it will improve the aerodynamics, you'll have a lighter boat and the best part of it: ....the looks of a sundancer.
 
Oprah has that kind of authority!!!?????
 
Four Suns said:
My 480 DB with QSM-11 diesels will only go 35 mph at 2300 RPMs and the engines are screaming. I'm coming from a 20 foot jet boat and my jet ski and jet dinghy all go faster so I find this performance unacceptable. Sea Ray is no help. They won't return my call. I am more frustrated than a 35 year old nerd living in my parent's basement who hasn't been laid in.. well.. ever. I feel with near 1400 HP, I should be able to go faster than my Chevette which only has 65 HP. Any suggestions? Should I write a letter to Brunswick? Maybe I should put some 32 blade props with more bite on the boat? Someone "in the know" told me I should have gotten the smaller QSB 380 HP engines as I can run them at 8000 RPMs all day.
Click to expand...

What's the purpose of this thread? Maybe you're right --- maybe we are "left with a bunch of 19 year old idiots".

This thread is an example.
 
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