Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: New Gm 620 Hp Engines

  1. #1
    BADASS38CHEVY
    JUST RAN ACROSS THE NEW GM 620 HP ENGINES JUST CAME OUT. CHECK IT OUT. www.gmpartsdepot.com .CLICK ON PERFORMANCE ENGINES AND CHECK OT THE 620 HP AND THE 720 HP ENGINES. CLICK ON PAGE 5 AND GO TO THE BOTTOM OF PAGE FOR THE 572 INCH ENGINE AND PAGE 6 FOR THE 720 HP ENGINE .

  2. #2
    LVjetboy
    Nice engines. But does that 720 rated hp 572 burn dock gas?

    jer

  3. #3
    GofastRacer
    Well, at 12 to 1 comp it all depends what they have at the dock!.

  4. #4
    HammerDown
    $13,600 for the 720 HP Motor...not bad at all. A little to much compression for a river Boat and a change of oil pan would make a great motor....no?
    I've got that amount in my change pocket for that Motor.

  5. #5
    Dave C
    I ran a 13:1 motor in my Daytona. There are no gas-docks out here that would fuel that.
    So I would drop the mortgage payment at the gas station and haul a bed full of gas cans to the lake.
    It was fun though

  6. #6
    230Stingray
    I am seriously considering the 620 hp version for my boat. I have chatted with Dennis Moore a few times about this motor. He thinks it would be a great torque monster but the cam is a little wild in it's present state and would probably cause a water reversion problem. He gave me some cam specs he felt would work well in this motor and still produce 575-600 hp and 650 ft pounds of torque and still have a smooth idle. I have run a ZZ502 in my boat for over 4 years now (ever since they came out and you had to assemble the top end yourself) with absolutly no problems. I'm still doing some research on a few things about this motor such as flywheel etc, but I think one of these will be in my future.

  7. #7
    HammerDown
    Why not the 720 HP one and run a thicker head gasket and or a Cam that would bleed of some compression?
    With Aluminum Heads and moderate Timing I would think 10.75:1 would work just fine on 93 pump gas...no?

  8. #8
    230Stingray
    Originally posted by HammerDown
    Why not the 720 HP one and run a thicker head gasket and or a Cam that would bleed of some compression?
    With Aluminum Heads and moderate Timing I would think 10.75:1 would work just fine on 93 pump gas...no?
    Interesting thought. Anyone else want to pipe in with some ideas?

  9. #9
    GofastRacer
    Of course it would work but you will make a big sacrifice in the power department!..You get what you pay for!..

  10. #10
    Dave C
    That 572 looks like a nice deal.
    I had a 10.9:1 in a 502. but I never had the brass nuts to run pump gas.
    I think 11:1 is pushing it but I heard it could be done but I did not want to be the guinea pig that tried it. Especially with the load put on by the jet.

Page 1 of 2 12 LastLast

Similar Threads

  1. Odd Engines
    By ck7684 in forum Jet Boats
    Replies: 29
    Last Post: 06-15-2007, 12:21 PM
  2. Two engines...
    By Sleek-Jet in forum Gear Heads
    Replies: 37
    Last Post: 03-04-2005, 03:57 PM
  3. New Gm 620 Hp Engines
    By BADASS38CHEVY in forum Sandbar
    Replies: 7
    Last Post: 11-15-2003, 05:12 AM
  4. Marine engines vs. Car/Truck engines
    By AntRant in forum Jet Boats
    Replies: 8
    Last Post: 08-15-2002, 11:32 AM
  5. engines
    By RYNORO1 in forum Gear Heads
    Replies: 4
    Last Post: 10-29-2001, 07:33 PM

Posting Permissions

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