PDA

View Full Version : Mercruiser 6.2 Engine - Anyone Running It?



Greg Guimond
08-21-2013, 08:19 AM
I am looking at a 2007 motor. It is the small block Mercruiser 6.2 which the guy says makes 320 HP. It does not have the fire graphic so I guess it is NOT the Scorpion model. I guess the 6.2L sits between the 350MAG MPI and the 383 Scorpion packages, but I'm not really sure as I'm more of a weedeater guy. Is anyone running this 6.2 to provide feedback. Does it require 93 Octane or can it run on 89 gas?

Thanks for any input.........:smile:

Tidbart
08-21-2013, 08:48 AM
I believe that is a 377 mag, 320 hp with 9.0:1 compression. So it should run on 87 octane.

Bob

osur866
08-21-2013, 09:32 AM
My engine started life as a black merc 6.2 and yes it's a 377 cu. motor will run all day on 87 in fact it will not run any better on 89-93. It should have a forged steel crank but does have the hyper. pistons good solid engine for what it is, prop this engine to turn 4,900 RPM's that's about where it runs out of power it will spin to 5450, limiter says 5200 but it's a soft limiter but again no news to spin it past 4900 just prop it there and you'll be better off.
Steve

Greg Guimond
08-21-2013, 10:11 PM
Thanks guys, that is good news on the octane as we can't get high test in many places on the water anymore. Would a 2007 6.2L "Black" actually be an EFI or would it be MPI? Also, dare I ask what a Blower would add to the ponies? Would the Blower need 93?

silverghost
08-21-2013, 11:38 PM
I am looking at a 2007 motor. It is the small block Mercruiser 6.2 which the guy says makes 320 HP. It does not have the fire graphic so I guess it is NOT the Scorpion model. I guess the 6.2L sits between the 350MAG MPI and the 383 Scorpion packages, but I'm not really sure as I'm more of a weedeater guy. Is anyone running this 6.2 to provide feedback. Does it require 93 Octane or can it run on 89 gas?

Thanks for any input.........:smile:


Greg~~~Don't tell me you are giving up those weed-wacker/egg-beaters and are finally putting a real Man's engine in a speedboat ? ;-)

Depending on the supercharger's boost pressure~~~if you do not boost to high you might be able to run it on standard pump gas (87-89).
Especially if you are running aluminum heads, and slightly colder sparkplugs, & a slightly richer fuel/air mixture .

Greg Guimond
08-22-2013, 07:38 AM
No way Brad.........I'm a rat-a-tat-tatter at heart. In fact I hooked The Mule up with a new "friend". The Mule is still a little standoff-ish but slowly warming up :rofl:

Greg Guimond
08-22-2013, 07:46 AM
My engine started life as a black merc 6.2 and yes it's a 377 cu. motor will run all day on 87 in fact it will not run any better on 89-93. It should have a forged steel crank but does have the hyp pistons good solid engine for what it is, prop this engine to turn 4,900 RPM's that's about where it runs out of power it will spin to 5450, limiter says 5200 but it's a soft limiter but again no news to spin it past 4900 just prop it there and you'll be better off. Steve


Thanks Steve for the feedback. Sounds like the 6.2 is a stout motor that also has nice fuel economy. Seeing as you have gone down the path and perhaps are the only guy on the site with a 6.2 Merc, what are the rough horsepower increase steps that a mild blower might offer? My thought is it would be nice to potentially get to an even 400hp from the stock 320 the motor has now. It is doing 62mph currently so my thought is 400hp would be a legit 70 light on fuel and that would be enough. The one caveat I would have is I can only get 89 Octane.


Appreciate any feedback .......... :biggrin.:

RickSE
08-22-2013, 02:37 PM
i was told once that the 6.2's had a Lunati crank, giving me the impression that they were nice set-up. The 6.2L was supposed to be a lighter replacement for the base 454 when the 496's came out.

Greg Guimond
08-22-2013, 08:36 PM
Interesting RickSE and what do you think a 6.2L would save in weight versus a 454 Magnum or a 502 Magnum MPI?

Greg Guimond
08-23-2013, 07:14 AM
My engine started life as a black merc 6.2 and yes it's a 377 cu. motor will run all day on 87 in fact it will not run better on 89-93. It should have a forged steel crank but does have the hyperuetectic pistons. good solid engine for what it is

What shop is the "go to" source for Whipple upgrades osur866? I'd like to understand what is involved to bolt on 80hp and run 89 Octane on a MX6.2 motor. Thanks

Greg Guimond
08-26-2013, 07:30 AM
It looks like the MX 6.2 MPI is 140lbs lighter than a 454 Magnum. I would have thought there would have been more of a weight savings.

osur866
08-26-2013, 06:19 PM
Greg check you inbox

joseph m. hahnl
08-27-2013, 04:46 PM
Thanks guys, that is good news on the octane as we can't get high test in many places on the water anymore. Would a 2007 6.2L "Black" actually be an EFI or would it be MPI? Also, dare I ask what a Blower would add to the ponies? Would the Blower need 93? All Merc stuff is 87 . You can adjust a blower for pump gas. a lot of the street aps are methanol .Also blower motors have a lower static compression and need forged innards to have any longevity:hangum: .9:1 is considered low but hyper pistons and a cast crank would put it out of the running for me." But". I suppose that people do it and get away with it on a daily bases:propeller:

osur866
08-27-2013, 07:10 PM
Stock 6.2 has a forged crank, hyper pistons yes I changed mine to 8.8:1 forged JE blower pistons

Greg Guimond
08-30-2013, 12:01 AM
Greg check you inbox

Big thanks to osur866! Steve gave me a whole bunch of "been there, done that" info on the 6.2. Thanks a lot Steve :thumbsup:

osur866
08-30-2013, 04:24 PM
Glad I could help Greg

Greg Guimond
09-23-2013, 07:02 PM
Does anyone happen to know what the "upcharge" dollars would have been for MX6.2 as compared to the standard 350 Magnum? I'm not sure how they priced these and I'm trying to figure out if given the choice, would the MX6.2MPI have been $8k-$9k extra bank above a 350MAG given that the 350MAG is 300hp and the MX6.2 is only 320hp.

mike o
09-23-2013, 07:25 PM
Greg, I think on my 2002 18C was around 4k, which included the bravo up grade also. Steve should maybe know, he bought his brand new. 2 bad your lower blew. I was hoping you where going to the Conn river Scream + Fly Pizza outboard run, this Oct. Its go fast outboard Disneyland

:yes:

Greg Guimond
09-23-2013, 07:34 PM
Thanks Mike. The only run I'll be doing is to the bank!

I did a little poking around on costs but there seems to be numerous 6.2 options so it is tough to figure out what a stock MX upgrade would have cost a new boat buyer in 2007.

mike o
09-23-2013, 09:32 PM
Ive been digging around for the last hr. Check this out, it will sort it out http://www.donzi.net/forums/showthread.php?47112-New-18-w-6-2L/page2&highlight=6%2C2+L+mpi 377 blue scorpion was $4800 in 2002 with the XZ bravo drive. 2006 Im reading $2300 for a 6.2l mpi upgrade from the 350mpi. But 6.2L was only sold with a bravo. Looks like $2300 for both on new 18 in 2006. So Im not sure my 4k figure was right.

Greg Guimond
09-24-2013, 07:02 PM
Thanks Mike, that was a really informative read. Between that and Steve's advice I think I have a good feel for this MX6.2 Bravo One combo. Thanks for the help guys.

Greg Guimond
09-24-2013, 07:05 PM
It is also interesting that the MX6.2 was only $2,500 more than a 350MAG. The MX6.2 seems like a stouter all around package and an extra 20hp for $2,500 in 2007 is reasonable.