320Da 350 mags vs 6.2 both V-Drives
- Thread starter TimC
- Start date
- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
What year? If it's the new design, bigger is better. The boat has more deadrise so it sits lower in the water. The small block is a bit of a stretch for this size boat, but there are many, many happy owners. Other than the 340, I think it's one of the best all-around family cruisers ever.
Expect to use quite a bit of throttle to get up on plane and cruise at a relatively high RPM (3700+). With that in mind, go for the bigger motors on this one. In either case, make them fill it up with gas and water and a few people for the sea trial. If it's got 1/4 in the tanks and only 2 people, you won't get a real look at the boat.
Expect to use quite a bit of throttle to get up on plane and cruise at a relatively high RPM (3700+). With that in mind, go for the bigger motors on this one. In either case, make them fill it up with gas and water and a few people for the sea trial. If it's got 1/4 in the tanks and only 2 people, you won't get a real look at the boat.
- Oct 6, 2006
- 12,155
- Boat Info
- 1996 450DA
- Engines
- 3116 Caterpillars
I have to agree with John that this is a great all 'round cruiser and one that is quite easy to handle.
Personally, I can't get excited about the difference between 2 different small block choices when it comes to power. You don't buy these boats to run races, pull water toys, etc, so what does a few seconds difference in planing times make?
I think I might be more concerned about the individual features or characteristics of the engines than power. For example, the 5.7 has been around forever, parts are plentiful and all the design issues were long ago ironed out......the down side is that you have old technology. The 6.2's are new technology and will be more forward compatable for upgrades than the 5.7 because the changes being made to improve the performance and features are being done on 6.2's, not on 5.7 base engines. The downside is that Mercruiser has a bad habit of "pulling product off the vine while it is still green" and you can expect some problems or concerns. For examples look on this site for topics I posted called "Heads up.............." dealing with Kool Fuel 3 and Mercruiser aluminum manifold failures.
Personally, I can't get excited about the difference between 2 different small block choices when it comes to power. You don't buy these boats to run races, pull water toys, etc, so what does a few seconds difference in planing times make?
I think I might be more concerned about the individual features or characteristics of the engines than power. For example, the 5.7 has been around forever, parts are plentiful and all the design issues were long ago ironed out......the down side is that you have old technology. The 6.2's are new technology and will be more forward compatable for upgrades than the 5.7 because the changes being made to improve the performance and features are being done on 6.2's, not on 5.7 base engines. The downside is that Mercruiser has a bad habit of "pulling product off the vine while it is still green" and you can expect some problems or concerns. For examples look on this site for topics I posted called "Heads up.............." dealing with Kool Fuel 3 and Mercruiser aluminum manifold failures.
dpmulvey
Active Member
- Dec 19, 2007
- 4,188
- Boat Info
- 1999/2007 330 Sundancer Hardtop.
- Engines
- 6.2 Merc Horixons
1.5:1 Velvet Drives
The 6.2 is a stroked 5.7. Stroked engines add horsepower by increasing Cubic Inches (377 V. 350 per engine) without boring the cylinders, therefore lessening the chance of problems associated with thin cylinder walls. Stroked engines produce more torque. The 6.2 is designed to cruise at 3800 RPM and redline at 5200. I don't care what the literature says about the v drive version of the 6.2 maxing out at 5000 RPM. That is a function of the v drive, not the engine. If you prop a v drive to max at 4800 to 5000 RPMs in accordance with the specs, you will be costing yourself immediate money in fuel consumption and long term money in engine wear as overpropping the engine places undue stress on the entire drive train. If you decide to buy a 6.2, drive it at 3800 and determine if you can stand the noise or if there is a way to insulate the engine room to mitigate the noise at cruise. The noise at 3800 is the only complaint I have with the 6.2. If I keep Saint Max, I shall be putting more insulation in the ER this winter.
FWIW, the 6.2 (with a ProCharger supercharger) is the engine being used on the '09 Corvette. The 6.2 with a marine version of the ProCharger will push 500 HP at WOT. It is a very well thought out engine.
FWIW, the 6.2 (with a ProCharger supercharger) is the engine being used on the '09 Corvette. The 6.2 with a marine version of the ProCharger will push 500 HP at WOT. It is a very well thought out engine.
My understanding is that the 6.2 is a totally different engine, not a modified 5.7.
There are some internal differences - but other things have come closer. For example the 350 mag is also fuel injected, not carb'd.
Normally I'm a much bigger fan of the 5.7, although I don't really like the mag version either, because I think they just pull too much power out of it and ask for a lot of rpms to obtain the HP ratings. But I think they do the same thing with the 6.2.
In this case, in a 320, you may like the 6.2 better because it will give you just a little more power and a little more torque.
It may be interesting to try to find out the gear ratio on the two boats.
There are some internal differences - but other things have come closer. For example the 350 mag is also fuel injected, not carb'd.
Normally I'm a much bigger fan of the 5.7, although I don't really like the mag version either, because I think they just pull too much power out of it and ask for a lot of rpms to obtain the HP ratings. But I think they do the same thing with the 6.2.
In this case, in a 320, you may like the 6.2 better because it will give you just a little more power and a little more torque.
It may be interesting to try to find out the gear ratio on the two boats.
