Engine wont rev in the 1/4 mile

Discussion in 'Engine Topic' started by Domobomb, Sep 14, 2017.

  1. Domobomb

    Domobomb Veteran Member

    194
    1
    Nov 10, 2009
    Windsor, Ontario
    Yes, ignition is all stock except the cap and coil which was causing EMI noise on my vette's efi so I put it on my Camaro.

    I built the heads/valvetrain 2 years ago.

    Thanks I'll do that. I did set the float levels properly a few years ago though. Maybe they need adjustment again.

    Well, I can calculate rpm based on trap speed and assuming torque converting isn't slipping much. I get 3560 rpm at my trap speed of 82 mph. It sits at 3600 rpm like it's hitting a rev limiter almost the last 1/3 of the track.

    [​IMG]

    The slow 60' time is more due to the street tires I was running - BFG Sport Comp 2 - 275/40R18, which I grabbed off my vette. Any brake torquing at all and it'll just sit an spin, so I had to launch at idle to control spin.

    You're right. The 18 second truck I was racing picked up more speed in the last 1/8th than I did. It was bracket racing though and the engine would die out the same way every time so I dialed in a 15.25 and won a few races lol.

    Total timing I have not checked. Initial was set to about 12. Carb isn't new but always ran great on the street, very strong down low. But I never really stretched the cars legs on the street like I did on the track.

    I have assembled a list of parts based on the feedback in this thread:

    [​IMG]
     
  2. 77 cruiser

    77 cruiser Veteran Member

    475
    14
    Nov 17, 2006
    Frostbite Falls MN
    Check your fuel line front to back. Any kinks? How big is it?
    Vent for the tank. Dia.?
    Fuel pickup sock in tank.
     
  3. Mwilson

    Mwilson Veteran Member

    I pay more attention to total timing set it around 36 then adjust your initial. Total is where all the power is, thats a huge variable you could be sitting at 22* and making no power.
     
  4. badazz81z28

    badazz81z28 Veteran Member

    14,528
    145
    May 4, 2001
    Las Vegas, NV
    The 60' foot time can just be wheel spin, I'm going to say I would suspect a fuel issue too. Your pump is probably bad and not supplying adequate fuel and pressures at RPM. The bog is tuning and a symptom of not enough fuel
     
  5. Z73

    Z73 Veteran Member

    137
    2
    Jul 21, 2012
    woodstock,IL
    Don't buy that distributer we put one in my buddy 81 and had nothing but trouble with it china made. just put a pertronix kit in the Stock GM distributer and like said in prevues post shoot for around 36 degrees total timing!
     
  6. 1980RS

    1980RS Veteran Member

    1,716
    41
    Jun 17, 2006
    MN
    Before you get all carried away with this and change too much stuff, which 600 Holley is this? and 1850VS, 80670VS or a 4776 DP?
     
  7. Damon

    Damon Veteran Member

    12,937
    20
    Nov 16, 2000
    Philly area
    Of all the parts you listed the only one I would buy at this point would be the fuel pressure gauge. And a length of flexible hose to hook it up so you can read fuel pressure WHILE YOU ARE DRIVING. Fuel pressure readings at idle in your driveway are meaningless. You need to see what happens UNDER ACTUAL LOAD. I just duck tape them to the outside of the windshield (temporarily!) to see if I'm holding pressure all the way down the track (or your local deserted back road).

    I'd almost guarantee you are just outrunning the fuel system from what you described. Make a run with the fuel pressure gauge taped to the windshield like I said and this will be OBVIOUS if it's happening. Fuel pressure will nose-dive followed shortly thereafter by the motor nosing-over, too.
     
  8. cadillac_al

    cadillac_al Veteran Member

    588
    36
    Apr 22, 2015
    Maine
    Great advice from Damon. Save your money and get the fuel verified. If it was ignition you would have some misfires or something.
     
  9. Domobomb

    Domobomb Veteran Member

    194
    1
    Nov 10, 2009
    Windsor, Ontario
    Thanks for the replies guys.

    I replaced the fuel pump, filter, and distributor. (Went with the PerTronix Flame-Thrower HEI)

    Also threw and old set of drag radials and 650 double pumper holley carb my dad had.

    Shifted at 6500 and it ran 13.5 at 103 mph. Here is the new vs old timeslip:

    60' 2.085 2.248
    330 5.821 6.275
    1/8 8.832 9.617
    MPH 82.44 72.30
    1000 11.395 12.633
    1/4 13.567 15.308
    MPH 103.65 82.72

    This time seems about right for my setup with 3.42 gears, right? Or do you think I'm still leaving something on the table.

    I was going to try a looser converter (Can brake torque to about 1800rpm right now), slicks, and 4.10 gears for next year. Any hope of hitting the 12s with my engine?

    Here is video:
     
  10. muscl car

    muscl car Veteran Member Lifetime Gold Member

    More rear gear like 3.73's and a looser converter like a 3500 stall , these two will definitely drop your 60' and also drop your overall ET
     
    79RedZ likes this.

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