Page 1 of 2 1 2 LastLast
Results 1 to 15 of 22

Thread: Mercruiser 6.2 Engine - Anyone Running It?

  1. #1
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0

    Mercruiser 6.2 Engine - Anyone Running It?

    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.........
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  2. #2
    Join Date
    Jun 2000
    Posts
    2,690
    Rep Power
    26
    I believe that is a 377 mag, 320 hp with 9.0:1 compression. So it should run on 87 octane.

    Bob
    Member - WAFNC
    1997 22 Classic (sold)
    1997 Formula 271 Fastech
    502 Mag MPI

  3. #3
    Join Date
    Dec 2006
    Posts
    905
    Rep Power
    18
    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
    2006 CLASSIC 18 WHIPPLED MX 6.2, BRAVO 1, STAINLESS MARINE EXHAUST, LATHAM STEERING, IMCO 2" SHORTY, LABBED MIRAGE PLUS

    TALK IS CHEAP, I'M FROM THE "SHOW ME STATE" SHOW ME

  4. #4
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    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?
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  5. #5
    Join Date
    Jul 2009
    Posts
    1,553
    Rep Power
    16

    Smile

    Quote Originally Posted by Greg Guimond View Post
    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.........

    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 .
    "BENCHSEAT 18" ~~YellowJacket~~ project owner~
    1929 Chris~Craft 28' Tripple Cockpit Mahogany Speedboat / A-120-A 845 Cu.In. 375 H.P. Chris~Craft V-8 racing engine.
    24' American Skier
    Super Eagle 454 HO Skiboat
    1991 454 SS Chevy Super Sport Pick-up for towing my "Toys".

    There is no such thing as going too fast ~ ~~
    OR~ Being too old~ for a new "Toy"!

    Brad Hunter
    Huntingdon Valley Pa (Just outside Philly)~
    Ocean City NJ
    silverghost1926@msn.com
    215 947 4676 (PA Home)

  6. #6
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    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
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  7. #7
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    Quote Originally Posted by osur866 View Post
    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 ..........
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  8. #8
    Join Date
    Mar 2000
    Posts
    2,593
    Rep Power
    27
    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.
    RickS-E

  9. #9
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    Interesting RickSE and what do you think a 6.2L would save in weight versus a 454 Magnum or a 502 Magnum MPI?
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  10. #10
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    Quote Originally Posted by osur866 View Post
    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
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  11. #11
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    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.
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

  12. #12
    Join Date
    Dec 2006
    Posts
    905
    Rep Power
    18
    Greg check you inbox
    2006 CLASSIC 18 WHIPPLED MX 6.2, BRAVO 1, STAINLESS MARINE EXHAUST, LATHAM STEERING, IMCO 2" SHORTY, LABBED MIRAGE PLUS

    TALK IS CHEAP, I'M FROM THE "SHOW ME STATE" SHOW ME

  13. #13
    Join Date
    Feb 2005
    Posts
    1,991
    Rep Power
    21
    Quote Originally Posted by Greg Guimond View Post
    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 .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
    machinist ,bore it deeper,ream it bigger, and lap it to a fine finish



    https://www.facebook.com/photo.php?v...=2&theater

  14. #14
    Join Date
    Dec 2006
    Posts
    905
    Rep Power
    18
    Stock 6.2 has a forged crank, hyper pistons yes I changed mine to 8.8:1 forged JE blower pistons
    2006 CLASSIC 18 WHIPPLED MX 6.2, BRAVO 1, STAINLESS MARINE EXHAUST, LATHAM STEERING, IMCO 2" SHORTY, LABBED MIRAGE PLUS

    TALK IS CHEAP, I'M FROM THE "SHOW ME STATE" SHOW ME

  15. #15
    Join Date
    Sep 2005
    Posts
    5,802
    Rep Power
    0
    Quote Originally Posted by osur866 View Post
    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
    1972 16 OB - C16B-63 - "Surface Tension" Resto Project
    1974 16 OB - DMR16106017-B - "The Mule"

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •