'03 340 with 6.2L or 8.1

C

cccjay

New Member
Jan 16, 2008
4
MN
Boat Info
86 340 Sundancer
Engines
V8s w V-Drives
found a '03 340 with a 6.2 L (320HP) at the right price and am hoping that performance does not suffer too terribly much. Does anyone have insight or know where i can get performance numbers compared to the 8.1(370 HP) (ie hole shots etc...)

thanks!
 
Last edited:
Which 03 340 is it? Is it the old hull, or the new hull? They are different in that the old one is flatter as I understand it. It'll plane earlier than the new hull, and it's more efficient. The ride is rougher in choppy seas.

The old hull does not have a port-side cockpit seat. The new one does (2003 1/2 - present)/
 
The 8.1's will do much better. While the horsepower numbers are not that far apart, there is a big torque advantage with the 8.1's.
 
Many of the posts on this forum discuss the possibility of the 320 being underpowered with the 350 mags and V-drives. Most people are happy, but you cruise at a higher than desired RPM. The 340 is a lot more boat than the 6.2 is more engine when compared to the 320/350 Mag combo.

I think the 340 w/8.1's is very nicely powered, if not a little more than you need. But, I just don't think the 6.2's w/V-drives will cut it. Read the posts about 370+ sized boats with 8.1's or any gas engines. Lots of complaints. That's what you'll get with the 340 and 6.2's. Lakes only, short distances, lots of no-wake zones, and an absolute steal - maybe.

What do you call the right price?
 
good question... I thought it was a good price but feel free to let me know what you think. The boat is in Duluth on Lake Superior

118k
gen and most options with 6.2. Looks like it has never been used.
 
Also if u travel alot ( stow lots of gear ) ur going to need the 8.1's . We'd pack our boat to the gills and she ran like a top in alot slop . Great boat. Great motors. ( 8.1's )

Id take a pass... Nothing like spending that kinda money and not being happy with performance.

Rob
 
The price is good, if the boat were ok. Realize that this boat, like a 40 footer with gas engines, will not sell very well when that day comes. Just look at his price. Can you imagine buying a boat during the second half of 03 for 250,000 (225,000?) and selling it 4 years later for 118,000?
 
I am happy with my 320 with 350 Mag's but am one of the few that seems to be at the top end of the WOT RPM Range. That being said, I have driven a 320 with 6.2's after putting 120 hours this season on my 320. My impression is that the 6.2's didn't give you that much more umph. I couldn't feel it that much, I had no buyers remorse, if the 320 had 8.1's I know I would have had buyers remorse, but that wasn't an option with v's on a 320. We boat ALOT with a 340 - with 8.1's and that seems to be a great setup. I would be nervous with 6.2's on a new style 340. That being said the 340 is quite a bit more boat and weight than a 320. I like power and the 6.2's in V's just don't have enough umph over a 350 Mag.
 
What is the dry weight, the weight of the boat with the 6.2's v. the 8.1's and the deadrise? What drives with the 6.2's v. the 8.1's? Anticipate a lot more fuel consumption with the 8.1s. If the hull is the 21 degree deadrise, you are going to need the extra power. If it is a 17 degree deadrise, either engine will do. The 6.2 is meant to cruise at 3800 to 4K whereas the 8.1 runs at 3450 to 3650. That said, you have to factor a noise difference and there will be a fuel consumption difference.

Both engines are for lack of better words, merely stroked versions of the next size down.
 
boat im looking at has the new body style (2003 340) with 21 degree deadrise... 14300 lbs. Seems to be a few new style 340s out there with the 6.2s. cant say im going to be doing much cruising with the price of gas but concerned about the resale... Your thoughts are appreciated. Thanks
 
Last edited:
cccjay said:
boat im looking at has the new body style with 21 degree deadrise... 14300 lbs. Seems to be a few new style 330s out there with the 6.2s. cant say im going to be doing much cruising with the price of gas but concerned about the resale... Your thoughts are appreciated. Thanks
Click to expand...

The new 330 is the replacement for the 320. I think the 6.2 may be just a little too small for that boat, but I feel that the 8.1's are over-kill. There's one heck of a jump in engine between these two, but unfortunately, that boat is somewhere in the middle and there's no other engine options in the middle.
 
dpmulvey said:
What is the dry weight, the weight of the boat with the 6.2's v. the 8.1's and the deadrise? What drives with the 6.2's v. the 8.1's? Anticipate a lot more fuel consumption with the 8.1s. The 6.2 is meant to cruise at 3800 to 4K whereas the 8.1 runs at 3450 to 3650. That said, you have to factor a noise difference and there will be a fuel consumption difference.
Click to expand...

If you are assuming the 8.1 will burn more fuel than the 6.2, that may be a faulty assumption. Tiara builds a 30 foot express with those two gassers and a diesel as options. The smaller block engines have to be run at a higher rpm level to achieve a good cruise speed and get less MPG than the 8.1s which get about a mile per gallon while cruising at a higher speed at just 3200 RPMs. I'll bet this boat would do the same and the 8.1s are bullet proof at that RPM. I run a 32 Open with 8.1s and it is a sports car in terms of performance compared to my 37 foot SR. It's not as fast (23knots cruise vs. 24-26) in calm seas but it is much faster in bad seas. We cruise that boat at 3500 RPMs and get about .8 to .9 miles per gallon for a range of 200 miles. The 8.1 has great torque for rough water performance and easy docking. I'll bet it will be quieter as well because of the low power settings compared to the 6.2. If you want to see specific numbers go to the Tiara web site and look at the 300 Open numbers. Totally different boat, but the engine question is the same.
 
Bigger displacement generally means more fuel at W.O.T.

But at cruise. . .. if one engine is spinning 4000rpm and the other is spinning 3600 RPM. . .That's a 10% difference; and nothing to sneaze at. Prop design is another huge factor.

I run 5.7LX's. W.O.T. on my boat is 4600 RPM. Cruise is 3000 RPM. My mechanic says never to run at 4000 RPM or higher for more than 60 seconds. His opinion (and I am inclined to agree) is that engine life is not linear with RPM.
 
comsnark said:
His opinion (and I am inclined to agree) is that engine life is not linear with RPM.
Click to expand...

Definately not! You, and he, are right. Wear goes up exponentially with RPM once you advance the throttle above a normal, 75 - 80% cruise setting.
 
I have an early 2003 340 with the 6.2's. Performance is good. Top speed is almost the same as the 8.1's. It gets on plane fine with tabs. It's not a rocket out of the hole, but it certainly does not struggle either. Gas consumption is better than average.
 
Hacman said:
I have an early 2003 340 with the 6.2's. Performance is good. Top speed is almost the same as the 8.1's. It gets on plane fine with tabs. It's not a rocket out of the hole, but it certainly does not struggle either. Gas consumption is better than average.
Click to expand...

Early 2003 - This should be the more efficient hull design than the one in question. Increase the deadrise and the hull sits deeper in the water on plane, gets on plane more slowly, and requires more push to stay on plane.
 
A fellow club member has a 340 w/ 8.1's. 40 GPH at fast cruise. Mrs. Robinson has a 330 w/ 7.4's and gets about 25+ GPH at fast cruise w/o the secondarys open. I have a 330 w/ 6.2's and honestly do not have enough water under the hull nor are the props to my liking to give you an accurate assessment as to GPH. I know it is under 25 as is.

I reread the thread. I was thinking 17 degree deadrise. If you are looking at a 21* deadrise, you will need the 8.1's for a comfortable cruise speed without excessive noise. However, I stand by >30GPH to do it. Both gas and diesel require 0.6 pounds of fuel per hour per horsepower to operate.

The 8.1 generates 370 HP at 4600 RPM. Gas weighs 6.1 pounds per gallon. 370 * 0.6 / 6.1 = 36.4 gallons per hour per engine = 72.8 gallons per hour at WOT.

Let's assume cruise is 75% of WOT. I realize the curve is not linear, but for the sake of discussion let's say it is.

370HP * 75% = 278HP

278HP * 0.6 / 6.1 = 26GPH * 2 = 52 GPH total.

Cruising at 75% WOT = 4600 RPM * 75% = 3450 RPM.

Gotta go pick up my daughter and new (as of yesterday) son in law. More to follow!

I'm back. So at 3450 RPM you will (in theory) burn 52 GPH.

Roll it back to 70% of WOT (3220) and following the same calculations you will burn 50 GPH.

It sucks, but it is what it is.

IMHO, in this day and age, instead of concentrating on the correct engine to put into a "V" hull design, Sea Ray is making a DRASTIC error in not advancing their technological prowess in a FAR more efficient hull design. The Cat is a HUGE player in Australia. It is breaking big ground here in center console fishers (27'-40') the racing circuit, and even in 30 foot trailerables that with twin 70HP Honda's will cruise at 18 knots and get 5MPG while doing it. As much as I like my dancer, if
Sea Ray wants me to continue boating in thier product, they are going to have to gear running efficiency toward my disposable income. They are going to have to rethink their product line. As long as they are under the Brunswick umbrella, I doubt that will happen.

My 2 cents.
 
Last edited:
You must log in or register to reply here.

Forum statistics

Threads
113,353
Messages
1,431,013
Members
61,205
Latest member
Jbrandt2002
Back
Top