PDA

View Full Version : 6.2MX w/Eddie Marine Thunder Exhaust



CBLavey
08-08-2004, 12:18 PM
For what it's worth to anyone out there running a Merc 6.2MX, IMHO an Eddie Marine Exhaust System is a great investment.
Before installing the system I was running a 22" Bravo 4 - blade at 5200rpm with four guys in the boat, full fuel and ice chest, etc. With the new system installed under the same load I'm now running a 23" and bumping the rev-limiter at 5350 rpm. I'll be trying a 24" next week. I'm just wondering if I could pull a 25" "labbed" Bravo 4 - blade? The boat is also about 75 lbs. lighter and sounds bitchin!! :cool:

rodnjen
08-09-2004, 11:59 AM
I am running the 6.2 Bravo III on my boat and really like the combination. Did you notice much change coming out of the hole? How about running at cruising speeds like 3000, 3500 or 4000 rmps, any significant speed or effeciency gained? :confused:
My boat is relatively new, I haven't even come close to bumping the rev limiter, but I am curious how it will run wide open.

Nokomis
08-09-2004, 06:06 PM
Its always cool when you spend the kind of money you did on the upgrade and it works out to your expectations.
But next time you post tell us it was you and 3 strippers out boating, ok? :D

DogHouse
08-09-2004, 06:19 PM
Is the 6.2 based on the new GM small block series with the symmetrical exhaust ports, or is it the old standard small block port layout? I've been thinking that a pair of aluminum LS-1 motors could make the basis for a nice combo in a boat, but wasn't sure about availability of decent exhaust manifolds for the new heads.
Thanks,
-Brian

Nokomis
08-09-2004, 08:52 PM
The 6.2 is a late model 350 with a stroker crank, not the new generation GenIII like the LS1. I think Malibu offers a marinized LS1.

powerplay230
08-11-2004, 03:47 AM
Thought the 377 Scorpion was the stroker 350, is the 6.2 different application or is it the 6.2 truck motor? Confused again.. :D

Havasu Hangin'
08-11-2004, 04:12 AM
Thought the 377 Scorpion was the stroker 350, is the 6.2 different application or is it the 6.2 truck motor? Confused again.. :D
I think the 6.2 is the stroker 350 (383), and the 377 Scorpion is a bored 350.

sigepmock
08-11-2004, 06:26 AM
Pulled this from the Merc website for the 6.2L MPI
Specifications
HP: 320
kW: 239
SmartCraft: Yes
Displacement Liter/CID: 6.2/377
Cylinder/Configuration: V-8
Bore & Stroke (in): 4.0 x 3.75
Bore & Stroke (mm): 101 x 95
Compression Ratio: 9.0:1
Fuel System: MPI
-The new multiport fuel injection (MPI) system features high-quality, marine-specific componentry for unmatched performance and increased throttle response.
-The MX 6.2 MPI features the powerful ECM 555 for unmatched engine-management capabilities.
-Long-stroke 377CID/6.2L engine customized by MerCruiser for high torque and more horsepower.
-Forged-steel crankshaft and special profile roller camshaft for more power and longer life.

powerplay230
08-11-2004, 04:17 PM
Sounds like H.H. was right again and I was confused again.Thought the Scorpion was a whole different motor since it was rated at 377hp instead of 320hp. Seems like the only way I learn anything is to open my yap and be wrong...
Rick
so much for only learning one thing a day (j/k) learn a LOT here and appreciate it.

77charger
08-11-2004, 06:21 PM
I think the 6.2 is the stroker 350 (383), and the 377 Scorpion is a bored 350.
let me correct you mr professor optima
stroked 350 std bore 377
.030 over 383 :D :D

Havasu Hangin'
08-11-2004, 06:43 PM
let me correct you mr professor optima
stroked 350 std bore 377
.030 over 383 :D :D
Here you go, Mr. Square guy:
377 = 4.155" x 3.48" (5.7" or 6.00" rod)
400 block and a 350 crank
383 = 4.030" x 3.76" (5.565" or 5.7" or 6.0" rod)
350 block and a 400 crank
Pick yer poison. Add a couple of 6 volts...if you really want to slow it down...

77charger
08-11-2004, 07:31 PM
Here you go, Mr. Square guy:
377 = 4.155" x 3.48" (5.7" or 6.00" rod)
400 block and a 350 crank
383 = 4.030" x 3.76" (5.565" or 5.7" or 6.0" rod)
350 block and a 400 crank
Pick yer poison. Add a couple of 6 volts...if you really want to slow it down...
:D :D Its only my lake cruiser so weight aint a factor as long as the squares play all day.The boat below dont slow down though its for the speed runs

CBLavey
08-11-2004, 08:19 PM
I am running the 6.2 Bravo III on my boat and really like the combination. Did you notice much change coming out of the hole? How about running at cruising speeds like 3000, 3500 or 4000 rmps, any significant speed or effeciency gained? :confused:
My boat is relatively new, I haven't even come close to bumping the rev limiter, but I am curious how it will run wide open.
Picked up a couple of miles per at 4000 rpm though I haven't checked speed against a GPS. There is a significant difference out of the hole but more so in the midrange. I haven't really measured fuel economy but I can run Mojave from Katherine's to the dam and back, including some skiing, on under 50 gallons - no problem. The 6.2 - in my boat, is very efficient. :cool: :cool:

northern baja
08-17-2004, 03:28 AM
the 6.2 murcruisers and the 377 racing motor have the same bore and stroke. The point that confuses me is the WOT RPM range is the same 4800-5200 and the advertised compression ratio is the same on all three (320,340, and 377 HP).
I'd like to fully understand the difference.