Is this the right rod for a C rotor hemi??

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by Scotttrod, Apr 20, 2014.

  1. REEHL EQUIPMENT

    REEHL EQUIPMENT Active Member

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    Well, unlike a lot of others here, you admitted to making a mistake.

    A lot of others here wouldn't do that.

    The mistakes will serve you well later on.

    Hang in there, it will get better.

    I know from experience.
     
    #21
  2. Scotttrod

    Scotttrod Member

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    Thanks...... pressing on. will run alky soon.......
     
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  3. LeWhite

    LeWhite BB/Alt

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    qft

    Little men have big heads Big men have little heads. Ask me how I know.
     
    #23
  4. overkill69

    overkill69 Member

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    hemi

    We ran a BAE for the first time last season and learned a valuable lesson like you...measure the compression ratio! We bought a supposedly proven engine and ran 16 mediocre passes. No matter what anybody says the only thing that matters is how much liquid you poured into it. Ours was below 10-1 so a little less destructive than your combo.

    Speaking of destruction, keep in mind what you did to that crankshaft. Even if it mags perfect and stayed straight it was abused. I wouldn't replace it, but i'd consider how many runs I wanted to put on it carefully.

    I had a post like yours last fall looking for hugs after a crank broke.lol.
     
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  5. Mark Leigh

    Mark Leigh Member

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    The best thing that can come from this is that you will expand your experience and make you a better engine builder ---anybody who is any good has a list of Boo Boo's too !
     
    #25
  6. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    compression

    overkill has it right on the head on cc'ing the motor. The piston mfg, so and so can tell you what it's supposed to be, but until you pour the motor, you don't know what it actually is. in my early years of driving/tuning, we had a motor that was 'supposed' to be at 10.8 that ended up being at 11.8 when I poured it. We bought a custom piston that was supposed to be 10.8 with a 63 gasket. it was 10.6 with a .042. The mfg finally made it right but the moral of the story if you can get 100cc to go, that's the compression....

    Also when you rebuild, you may want to consider a short rod or decked piston in 1, 3 and 6. We go about .030 short on those cylinders. Also if you cc the motor, make sure you don't cc it with a short rod in No. 1. Seen that happen.

    A -3 line will only flow about a 76-80 nozzle, so it won't flow any more even without a nozzle, so above that you are not really doing much in terms of richening it. The other thing you can do to help cylinders is use individual cylinder timing on the grid to pull a couple degrees out of the problem cylinders.
     
    #26
  7. Scotttrod

    Scotttrod Member

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    Yes, I'll be a checking and rechecking fool on this build. I have never missed like this on any of my other motors, what an expensive embarrassment.

    I have yet to order rods, thanks for the tip on going a little shorter. Crank is with the mag guy now, then off to get a sleeve.....

    4.310 .100 tall TFX 96 cast in 2005, if anyone has extra sleeves......

    Thanks
     
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  8. GregM784

    GregM784 Member

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    Amen ! ! !
     
    #28
  9. TAFC 5 81

    TAFC 5 81 Member

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    Scottrod, don't beat yourself up too much. My first car was a BB/FC (1977). We purchased a BBC longblock (less blower and injector) from another BB/FC racer. When we disassembled it we noticed there had been some minimal contact between the flat area of the piston and head. We also noticed they had the top of the rods (Howards) repined to drop the piston down some. resulting in an odd .413 long rod. We replaced them with .400 to drop it slightly more to play it safe. But we switched out the Vertex mag for a Supermag II (and failed to notice the 24 degree advance); resulting in a pitched head gasket that damaged the block (lucky we were on an 1/8 mile track). That wasn't the last blooper we would have either. At least now you know what the main issue is.
     
    #29
  10. Scotttrod

    Scotttrod Member

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    Enderle 1380

    Thanks, trying not to.

    I am also considering going Waterman pump from my 20.9 Enderle to hedge off any questions about the fuel system. (Some rumors that this particular gallon pump has had cover issues...... and goes away quick.
     
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  11. jody stroud

    jody stroud ZOMBIE Top Dragster

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    Save yourself some grief and buy a rage fuel pump. There is a reason 1 -10 in nitro funny car and most of the hitters in nostalgia funny car run them. Same price as a waterbucket and come with all the mods to prevent cavitation built right in to start with.
     
    #31
  12. Soldierboy0098

    Soldierboy0098 Active Member

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    Pumps

    Jody once again makes a good point. Enderle pumps are funny things, I have heard of guys that have had no problems with them in IHRA TAFC and then I have had well known teams tell me that they have seen cavitation at high rpm's but the pump checked out fine, probably ran up to only 8000 rpm engine speed on the bench. The moment they switched the pump to a waterman or rage the problems went away with the same tuneup. They are a bit expensive in comparison but a good fuel pump will save a lot of headaches and money in the future. The Enderle may work fine for you once the pistons stop making contact with the heads but if you do decide to replace the pump I would definitely go with the Rage pump. I have just had my whole system flowed by Mike and his pumps come ready to run where as the Waterman had to be modded for anti cavitation.

    Bet wishes,
    Trevor Sherwood
     
    #32
  13. Dave Germain

    Dave Germain New Member

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    Parts?

    You mentioned something in your initial post about buying most of your parts from people here? I truly hope you arent buying used connecting rods? There are lots of parts that you can get away with buying used, but rods aren't one of them. Always buy new rods. There is no telling how many runs are on a set of used rods...By the way- a few years ago I had a big chamber Walt austin motor put together by a reputable race engine shop. First run it blew itself to pieces- unfixable pieces. The machinist told me later that he had calculated the compression wrong. Not to mention that 7 of the 8 rods kissed the heads. The only one that didn't was the one he measured. The moral of the story- check everything yourself and dont believe every wanna be engine builders BS. I wouldn't take my can opener to that guy again. He admitted he was wrong but never made good on anything....Dave Germain
     
    #33
  14. Scotttrod

    Scotttrod Member

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    New Rods

    Dave,

    The rods were new and bought from a friend that is on here. There were not bearing prints and there were sealed in original box. He changed his combo and offered them to me.
     
    #34
  15. blown1969camaro

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    we like it when pistons kiss the heads :)
     
    #35
  16. john348

    john348 Top Alcohol

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    how did you figure your compression
    did you actually fill the cylinders BDC and TDC with a barrett?
    new rods dont always mean they are ok, Right Tim S??
    I always keep my fingers crossed for the first pass..
     
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    Last edited: Apr 25, 2014
  17. Dale Finch

    Dale Finch New Member

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    The thing about timing is you can always creep up. I think thats a lot of timing with a lot of compression. Some of the really fast TAFC's hauled butt in the 9,s. If you have never used a stretch guage before, stop spend the money first on buying one....then fix the engine. Did any of them feel like they were loose or different when you were taking it apart. Once you use one you'll be surprised in the difference in the torque to attain the proper stretch vs just straight torque.

    When you say you have 10.8 I assume you know its poured so that shouldn't be in question. Will is right. Interesting Will you run down in those holes. Not the holes I ran down. Gotta run
    Dale
     
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  18. AFC357

    AFC357 New Member

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    RIGHT!!!!!!!!!!!!!!!!!!!!! hahahaha
     
    #38
  19. Scotttrod

    Scotttrod Member

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    Ooppps


    The cylinder was poured with the 4.25 crankshaft, I measured wrong with rod length (math in public).

    I will get a stretch gauge, have not used one before....... Learning every day :cool:
     
    #39
  20. john348

    john348 Top Alcohol

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    lets say you shortened the rod .250 to to compensate for the half inch longer stroke
    the compression still increased
    you still need to pour it
    i like to keep the piston on the head myself
     
    #40

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