Survey by Qualaroo
+ Reply to Thread
Results 1 to 9 of 9

Thread: pick improvment tip for mehran cng

  1. #1
    Senior PakWheeler Follow
    theboss's Avatar
    Join Date
    Feb 2007
    Location
    Oil Well
    Age
    31
    Posts
    2,447
    Follows
    1
    Following
    0
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default pick improvment tip for mehran cng

    Many users complain about bad pick up of Mehran on CNG. Well here is a tip for mechanically inclined PW'ers.

    Swapping in crank shaft and connecting rods form Khyber engine will elongate your stroke to 77mm and raise your compression ratio to 10.7:1 and displacement to 851cc. Crankshaft may require some machine work to fit properly and cam timings should be done again to reflect longer stroke.

    Long stroke with matching cam timings will greatly improve your low end torque making your pick up stronger and yielding better CNG mileage.

    Beware that after this modification, you should NOT run your engine on regular petrol, it will knock pretty bad and self destruct. It will require high octane petrol for long term running. Engine redline will reduce to 5000 rpm versus 5500 rpm original.

    It took a hell of a time at sher shah to figure this out. Hope it was worth.

  2. #2
    Senior PakWheeler Follow
    theboss's Avatar
    Join Date
    Feb 2007
    Location
    Oil Well
    Age
    31
    Posts
    2,447
    Follows
    1
    Following
    0
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    now where are all whining complaining owners of Mehran?? Are you all off to sher sha or what??

  3. #3
    Senior PakWheeler Follow
    psyb0rg's Avatar
    Join Date
    Sep 2005
    Location
    San Jose
    Age
    30
    Posts
    3,022
    Follows
    0
    Following
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    Are you sure the engine woudl knock at 10.7? It doensn't seeem THAT much....And have you doen this mod? Got any pics? Where'd you get the crank grinded/machined?
    "The rough, hard idle swells up and out from under the car, ricochets off other cars, and rams into the ears of the driver, the spectators. You think twice about a 383 Road Runner, but a hemi only once -- and let it pass."

  4. #4
    Senior PakWheeler Follow
    LOGAS's Avatar
    Join Date
    Dec 2006
    Location
    Lahore
    Age
    57
    Posts
    1,921
    Follows
    0
    Following
    0
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    @Theboss...................

    What a TIP.................lol......its not a dream, its nightmare.....lol.....U dont know the after effects of it.
    Economy With Security And Durability.

  5. #5
    Senior PakWheeler Follow
    kkoool's Avatar
    Join Date
    Apr 2005
    Location
    Islamabad
    Age
    35
    Posts
    1,661
    Follows
    2
    Following
    0
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    1

    Default

    worn-out valve seats are the after effects
    AE 86

  6. #6
    Senior PakWheeler Follow
    kiani1's Avatar
    Join Date
    Jan 2005
    Location
    Rawalpindi
    Age
    27
    Posts
    3,238
    Follows
    0
    Following
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    Worn Out valves, Rough Idling, Blown Gaskets are what we are looking at !
    B2 Innovations - Events & Media Managers

    http://www.facebook.com/group.php?gid=129332754507

  7. #7
    PakWheeler Follow
    huebleu's Avatar
    Join Date
    Dec 2005
    Location
    Lahore
    Age
    32
    Posts
    459
    Follows
    0
    Following
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    one thing mehran owners cant compromise is its resale.
    utility dont matter much.

  8. #8
    Senior PakWheeler Follow
    n20ahsan's Avatar
    Join Date
    Sep 2006
    Location
    Larkana
    Age
    27
    Posts
    2,915
    Follows
    0
    Following
    0
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    The one doing all this will be ruining his car's engine

  9. #9
    Senior PakWheeler Follow
    theboss's Avatar
    Join Date
    Feb 2007
    Location
    Oil Well
    Age
    31
    Posts
    2,447
    Follows
    1
    Following
    0
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Problems Posted
    0
    Problems Solved
    0
    Best Answers
    0
    Good Answers
    0

    Default

    10.7:1 compression ratio is not high for CNG. Even petrol can run this much if you use high octane or your engine is cold.

    And why worn valves and blown head gasket???? True if conversion is done by an average mechanic under tree shade!!

    I took measurement to do this. Sure its not a direct swap and requires some machine work involved but at least result seems promising as an experiment. Off course you will have to adjust your bores or else too much bore/stroke can ruin you engine. I don't own a mehran so cant do this mod for vehicular purpose however using mehran engine is something else where this mod will be adopted.

+ Reply to Thread

User Tag List

Posting Permissions

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