Engine Dieseling - Options?

Small Block Mopar Engine

  1. 33IMP

    33IMP Well-Known Member

    Messages:
    851
    Likes Received:
    864
    Joined:
    Jul 3, 2020
    Location:
    Taxifornia, soon 2b arizona
    Local Time:
    11:40 PM
    Shut it off in gear, with your foot on the brake.


    I cant believe some other smartass didnt beat me to it.
     
  2. RustyRatRod

    RustyRatRod I was born on a Monday. Not last Monday. FABO Gold Member

    Messages:
    70,700
    Likes Received:
    45570
    Joined:
    Jun 7, 2010
    Location:
    Georgia
    Local Time:
    2:40 AM
    I never try to set the air screws the "same". That's just not the right way. You adjust with the vacuum gauge. Get each one to the highest reading on the vacuum gauge, in gear if an auto and then one half turn leaner. "Wherever" they end up is where they are supposed to be after that. That's how it's always worked best for me.
     
    • Agree Agree x 3
    • RammerJammer75

      RammerJammer75 Well-Known Member

      Messages:
      1,276
      Likes Received:
      1579
      Joined:
      Aug 28, 2020
      Location:
      Kingsport, TN
      Local Time:
      2:40 AM
      Same here. Never had a single problem with it.
       
    • 512Stroker

      512Stroker We are all here because we are not all there.

      Messages:
      2,214
      Likes Received:
      1591
      Joined:
      May 30, 2016
      Location:
      Freedom, MO
      Local Time:
      1:40 AM
      You fool, not like that, you shut it off in gear with the parking brake set.
      I thought every one knew that. LOL
       
      • Like Like x 1
      • 512Stroker

        512Stroker We are all here because we are not all there.

        Messages:
        2,214
        Likes Received:
        1591
        Joined:
        May 30, 2016
        Location:
        Freedom, MO
        Local Time:
        1:40 AM
        Glad to hear you are making progress.
        LIke I mentioned before this is a balancing act with the idle mixture screws and timing dont get frustrated take baby steps in the process and you will get it.
        Like Rusty said use a vacuum gauge to set the mixture screws - SLOWLY.
        There is most likely nothing wrong with your carb gutting it know is just going to throw a curve in your tuning process. I would work with what you got.
         
      • beanhead

        beanhead Well-Known Member

        Messages:
        261
        Likes Received:
        269
        Joined:
        May 21, 2017
        Location:
        wackyfornia
        Local Time:
        11:40 PM
        Well yeah, I didn't mean to say you just make them the same for the sake of making them the same but they should end up close on a 4-corner carb ....I shoulda been more clear. But,1/4 turn out on the secondary and 1/2 on the front tells me something's not right.
         
      • 33IMP

        33IMP Well-Known Member

        Messages:
        851
        Likes Received:
        864
        Joined:
        Jul 3, 2020
        Location:
        Taxifornia, soon 2b arizona
        Local Time:
        11:40 PM
        Parking brake? What is this "parking brake" of which you speak?
         
      • 512Stroker

        512Stroker We are all here because we are not all there.

        Messages:
        2,214
        Likes Received:
        1591
        Joined:
        May 30, 2016
        Location:
        Freedom, MO
        Local Time:
        1:40 AM
        It's that funny little pedal next to the drivers side kick panel that no one ever uses. LOL
         
      • j par

        j par Well-hung Member

        Messages:
        27,552
        Likes Received:
        14965
        Joined:
        Jul 2, 2014
        Location:
        Portland Oregon
        Local Time:
        11:40 PM
        Somehow I read it that you have 11.5 to 1 compression. Then I reread and notice it's probably 10.5 to 1...
        I retract my initial diagnosis after rereading and agree that it's likely not an octane issue but the tuning issue..
        "Assuming" you have the correct torque converter.. but that much duration in your cam it's going to sound super cool idling at 900 or 850... But it's not good for it..
         
      • yellow rose

        yellow rose Overnight Sensation FABO Gold Member

        Messages:
        27,904
        Likes Received:
        24170
        Joined:
        Jun 19, 2015
        Location:
        Central Washington
        Local Time:
        11:40 PM

        When you get it right, the RPM drop should be no more than 150 RPM from neutral to in gear.

        Usually when you see a big drop like that, the curve in the distributor is wrong. Once you clean that up, you’ll probably have to take some fuel away at idle.
         
      • yellow rose

        yellow rose Overnight Sensation FABO Gold Member

        Messages:
        27,904
        Likes Received:
        24170
        Joined:
        Jun 19, 2015
        Location:
        Central Washington
        Local Time:
        11:40 PM
         
      • billsdartgt

        billsdartgt FABO Gold Member FABO Gold Member

        Messages:
        588
        Likes Received:
        362
        Joined:
        May 12, 2019
        Location:
        Puyallup, WA
        Local Time:
        11:40 PM
        @yellow rose - Tim, I installed the FBO plate at 12, all in timing with initial gives me 32 degrees total, also checked at 20 degrees initial the advance starts around 23/2400, all in by 2800, checked lower initial and the all in still just adds the 12 limited by the FBO plate

        regarding the torque convertor, plans are to eventually get something suited for the cam in the 2800/3000 range, I do not know what is in there right now though,

        regarding the idle screws - I chocked them down as noted earlier, car is still rich, and since I juiced it I can tell the juice is mixed enough to become part of the fuel hitting the carb, its part of the exhaust smell richness - to me something is off with the carb as most here have mentioned it needs tuning, however even choking the idle screws almost shut its still pulling the fuel - Saturday morning will start a fresh set of rechecks, and as mentioned I may put the 670 I have on, I know it to be fully functional and responsive to adjustments - at least if I have a similar issue I can also eliminate strictly a carb issue.

        @jpar - yes the car did measure out to have roughly 10.5-1 static compression, the pistons per their part number they are the TRW 11.5-1 pistons though.

        aggravating shiznit for sure LOL - all the comments are appreciated
         
        • Like Like x 1
        • Thanks! Thanks! x 1
        • j par

          j par Well-hung Member

          Messages:
          27,552
          Likes Received:
          14965
          Joined:
          Jul 2, 2014
          Location:
          Portland Oregon
          Local Time:
          11:40 PM
          If you added a couple gallons of race fuel would that hurt anything?.. again your local Baxter's will have five gallon cans of it and that's the hard part cuz it's expensive there. Pour 2 gallons in of the can swish it around and take it for a good ten mile drive.. come back and watch it turn right off..
          personally you could run it as rich as you wanted to in my opinion and if it doesn't have spark how's it going to ignite? The extra Rich fuel would be cooling the cylinder... The 11 to 1 Pistons are only 11 to 1 assuming a certain combustion chamber size...
          I'm not quite sure how Pistons can make that claim..
          There's no question you need for things to make your car run, air, fuel, spark, compression... I'll have to go back to the first post and see what plugs are using and calling cold... Are they just colored more than three threads from the bottom?... did I remember correctly you had 220 to 240 cranking pressure?..
           
        • RustyRatRod

          RustyRatRod I was born on a Monday. Not last Monday. FABO Gold Member

          Messages:
          70,700
          Likes Received:
          45570
          Joined:
          Jun 7, 2010
          Location:
          Georgia
          Local Time:
          2:40 AM
          Have you checked cylinder pressure? What is it?
           
          • Like Like x 1
          • j par

            j par Well-hung Member

            Messages:
            27,552
            Likes Received:
            14965
            Joined:
            Jul 2, 2014
            Location:
            Portland Oregon
            Local Time:
            11:40 PM
            Treed ya, dummy...
             
          • RustyRatRod

            RustyRatRod I was born on a Monday. Not last Monday. FABO Gold Member

            Messages:
            70,700
            Likes Received:
            45570
            Joined:
            Jun 7, 2010
            Location:
            Georgia
            Local Time:
            2:40 AM
            Something is wrong somewhere. You say is has 220-240 PSI, yet the engine wants timing like it's a 7.5:1 motor. I'd be rechecking some things. There's no way in the world it will want that much timing with such great cylinder pressure. You sure it wasn't 120-140?
             
            • Agree Agree x 2
            • Like Like x 1
            • j par

              j par Well-hung Member

              Messages:
              27,552
              Likes Received:
              14965
              Joined:
              Jul 2, 2014
              Location:
              Portland Oregon
              Local Time:
              11:40 PM
              I'm not following your calculations for compression...
              11 to 1 Pistons don't make any sense to me... Unless they're saying that is at zero Deck with x cylinder head CC...
               
            • j par

              j par Well-hung Member

              Messages:
              27,552
              Likes Received:
              14965
              Joined:
              Jul 2, 2014
              Location:
              Portland Oregon
              Local Time:
              11:40 PM
              I think it's compression is much higher especially if it's wanting that much initial timing. And who would put together a motor with that cam with low compression...
               
            • RustyRatRod

              RustyRatRod I was born on a Monday. Not last Monday. FABO Gold Member

              Messages:
              70,700
              Likes Received:
              45570
              Joined:
              Jun 7, 2010
              Location:
              Georgia
              Local Time:
              2:40 AM
              Low compression engines demand less timing. High compression engines don't need a lot. His problem is the reverse of what it would be with too much compression.

              Now, if perhaps he had a 383 distributor in it and it was spinning backwards, that might explain it. I've seen that one first hand.
               
              • Like Like x 1
              • Thanks! Thanks! x 1
              • billsdartgt

                billsdartgt FABO Gold Member FABO Gold Member

                Messages:
                588
                Likes Received:
                362
                Joined:
                May 12, 2019
                Location:
                Puyallup, WA
                Local Time:
                11:40 PM
                numbers are correct - 220-230ish - I never had an engine with that high of numbers, hoping it means the rings are good LOL
                well I got back at the car this weekend, worked on my brakes, even if I could get the car happy running wise they weren't good enough to get out of the driveway with. I started off as I mentioned with my 670, re-jetted, rechecked everything just to be sure no issues from the last time I ran it, even checked the PV, went step by step on the install trying to make sure I paid attention to every detail for the install, even reset the kick down 100% properly, I only thought I set it right the first time, at least it is much closer. So after I get everything installed and start it up, try to kick down off the high idle from the choke - nothing doing - same sh*t as before - DAMN - I know this carb is good - so I do a little checking, I found my culprit, of course he had an installer who is partly to blame

                IMG_0595.JPG not sure when I set the throttle on the 750 but quite sure I set it up the same way, when I locked the cable down it was with the carb sitting in the choke position, so I basically locked the throttle open to high idle, the transfer slot exposed as a result was a source of the pain and suffering - right now car is at 850ish on idle with 22 degrees initial timing - no dieseling or kickback and no start issues - Go figure - since I have the 750 off I am going to take it apart anyway to recheck everything including the PV, once all checked I will put it back on and see how it does. right now I will be able to hit the streets for the first time since October last year when I started out to check some freeze plugs and strut rod bushings - what a run of crap, may get a better sense of what PV the 750 may like when Im out on the street with the 670, maybe
                 
                • Like Like x 1
                • yellow rose

                  yellow rose Overnight Sensation FABO Gold Member

                  Messages:
                  27,904
                  Likes Received:
                  24170
                  Joined:
                  Jun 19, 2015
                  Location:
                  Central Washington
                  Local Time:
                  11:40 PM
                  Wow. What is the @.050 numbers on your cam? That is a TON of cranking compression. Unless that cam is incredibly small at .050 it must be 8 degrees advanced.
                   
                  • Like Like x 1
                  • 33IMP

                    33IMP Well-Known Member

                    Messages:
                    851
                    Likes Received:
                    864
                    Joined:
                    Jul 3, 2020
                    Location:
                    Taxifornia, soon 2b arizona
                    Local Time:
                    11:40 PM
                    One tooth off on the timing set? Or maybe a misinterpretation of a multi keyway set.
                    Ive only had one engine that ever had that much cranking pressure, an oil burning, worn out 396 chevy. It had a whole bunch of flat cam lobes.
                     
                  • cudamark

                    cudamark FABO Gold Member FABO Gold Member

                    Messages:
                    8,053
                    Likes Received:
                    929
                    Joined:
                    Mar 14, 2009
                    Location:
                    San Diego
                    Local Time:
                    11:40 PM
                    You had one too eh? I had (for a very short time) a '69 Chevelle 396 4 speed with 220+ compression in each cylinder and it would kill mosquitos for miles around! That thing had such bad valve seals that it would oil foul plugs in 100 miles. Rings were fine, did a leak down test and it passed with flying colors. I was glad someone made me an offer for the car that I just couldn't refuse.
                     
                  • billsdartgt

                    billsdartgt FABO Gold Member FABO Gold Member

                    Messages:
                    588
                    Likes Received:
                    362
                    Joined:
                    May 12, 2019
                    Location:
                    Puyallup, WA
                    Local Time:
                    11:40 PM
                    247/254 @ .050 - 108 lobe separation, 508 lift intake/exhaust - cam had 4 degrees built in, I installed retarded it so it would have 2 degrees, changed the ICL from 104 per the cam card to 106 per the mgi speedware website - cam was degreed in - will see how it does next weekend, if the valves don't rattle I will be OK for now
                     
                  • Phreakish

                    Phreakish Well-Known Member

                    Messages:
                    1,192
                    Likes Received:
                    782
                    Joined:
                    May 28, 2015
                    Location:
                    N. Idaho
                    Local Time:
                    11:40 PM
                    What are you running for lifters? Preload?
                     
                  1. This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
                    By continuing to use this site, you are consenting to our use of cookies.