performance woes

Discussion in 'Technical' started by 70maverick173, Sep 7, 2004.

  1. 70maverick173

    70maverick173 Member

    Joined:
    Feb 25, 2004
    Messages:
    28
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Carson, Iowa
    Vehicle:
    1970 1/2 Maverick
    I have recently done a v-8 swap into my maverick and it is running kinda wierd. The engine has a high speed sputter. It only does this around 3500rpm and up and at full throttle. When you cut to half throttle it goes away. under normal driving conditions it does not happen. Only during rapid acceleration. It also only does it while driving on pavment and not on gravel because on gravel the tires just spin. The following parts have been rebuilt or replaced to fix the problem at no avail. The carb, distibuter, cap and rotor, spark plugs, plug wires, ignition box. I have no idea what could be causing this problem. A new coil was also put on during the swap. Any and all advice would be great. It is a 302 with a wieand 180 intake, carter 4brl carb, summit headers and cherry bombs. Have any of you experiance this kind of problem. It sounds like a drum roll only deeper. My only thought is th fuel pump.
     
    70maverick173, Sep 7, 2004
    #1
  2. courier11sec

    courier11sec Member

    Joined:
    Apr 19, 2003
    Messages:
    2,589
    Likes Received:
    8
    Trophy Points:
    117
    Location:
    Tucson, AZ
    Vehicle:
    '72 2d to hold my trailer down with.
    Where do you have your timing?
    Sounds like severe detonation to me.
     
    courier11sec, Sep 7, 2004
    #2
  3. don graham

    don graham MCG State Rep

    Joined:
    Mar 10, 2002
    Messages:
    15,800
    Likes Received:
    16
    Trophy Points:
    302
    Location:
    arizona city, az.
    Vehicle:
    70 mav, 71 grabber, 73 Comet, 2004 f-250 crew cab diesel, 2001 f-250, 2004 explorer, 2007 Gold Wing trike.
    my first thought was the fuel pump too. however it could be the fuel filter, or it could be the carb. maybe the floats are set to high. hard to say. check the timing and replace the fuel filter are the cheapest thing. a fuel pressure regulator will tell you if the pump is keeping up with the demand. hard to tell without hearing it but have you used stock ignition and coil parts. might just not be getting enough spark. should go higher than 3500 stock, but you never know under hard acceleration.
     
    Last edited: Sep 7, 2004
    don graham, Sep 7, 2004
    #3
  4. Maverick Man

    Maverick Man The Original Maverick Man

    Joined:
    Mar 12, 2002
    Messages:
    3,559
    Likes Received:
    41
    Trophy Points:
    137
    Location:
    California
    Vehicle:
    Two 1973 LDO Mavericks (one 4 Drag one 4 driving like Mad on the roads :) ) also have a 75 6cyl Stock! Ok, well sort of Stock :P
    i had a very simlair problem at 5200 rpms. it had a consitant pudder only on load. i changed everything, wires, coil, MSD 6Al box, plugs, fuel pump, rebulit the carb twice, etc. i found out it was the battery... the battery wasn't holding a charge or something or the alternator wasn't putting out enough to stand alone. either way i put a new battery in, problem solved DOH! i just put in a 100 amp alt recently too just incase.

    good luck let us know what happens
     
    Maverick Man, Sep 7, 2004
    #4
  5. tim keck

    tim keck truckdrivintrailertrash

    Joined:
    Jul 4, 2004
    Messages:
    1,991
    Likes Received:
    7
    Trophy Points:
    111
    Location:
    sharps chapel,Tn
    Vehicle:
    '72 Comet, '75 Maverick, '85 F150 4x4 ,'93 F150,'75 F100,'77 Jeep Wagoneer,'91 Dodge D250 Cummins,'90 F150 xtra cab 4x4, '93 F150 4x4
    Do you have a vaccum advance?If so the diaphram may be bad.My 73 grabber (302,c4)would cut out under a load & thats what it was on it.
     
    tim keck, Sep 7, 2004
    #5
  6. littleredtoy

    littleredtoy Seth

    Joined:
    Apr 27, 2002
    Messages:
    4,050
    Likes Received:
    15
    Trophy Points:
    162
    Location:
    North Carolina, Triangle Area
    Vehicle:
    '74 Comet GT
    I would guess it's a distributor or advance problem as well.


    Seth
     
    littleredtoy, Sep 7, 2004
    #6
  7. Max Power

    Max Power Vintage Ford Mafia

    Joined:
    Aug 7, 2002
    Messages:
    1,230
    Likes Received:
    1
    Trophy Points:
    0
    Location:
    St. Paul, MN
    Vehicle:
    1977 Maverick, 1969 Mustang Sportsroof, 1970 Mustang Grande Project
    Vacuum advance is negated at high rpm or under extreme load.
     
    Max Power, Sep 8, 2004
    #7
  8. 71gold

    71gold Frank Cooper Supporting Member

    Joined:
    Apr 9, 2002
    Messages:
    26,589
    Likes Received:
    2,935
    Trophy Points:
    978
    Garage:
    1
    Location:
    MACON,GA.
    Vehicle:
    '73 Grabber
    you didn't mention that you had this prob. with the 6 gyl.i suggest putting the 6 cyl. back in. if the prob. goes away, it was the v8. sounds simple to me.:slap: ...frank...
     
    71gold, Sep 9, 2004
    #8
  9. Earl Branham

    Earl Branham Certified Old Fart

    Joined:
    Mar 9, 2002
    Messages:
    6,367
    Likes Received:
    201
    Trophy Points:
    218
    Garage:
    1
    Location:
    Lugoff, SC
    Vehicle:
    '69.5 Maverick 302, T-5, Grabber Green
    Frank; guess you have your power back!!!!!
     
    Earl Branham, Sep 9, 2004
    #9

Share This Page