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Thread: 377 Break in procedure

  1. #1

    377 Break in procedure

    I have been hearing conflicting procedures for new motor break in. The old adage is break it in hard and it will be fast or give tlc for 500 miles. I read one motor builder suggest that to properly seat the rings the rings need to be loaded and unloaded [full throttle then let off the pedal and allow the engine to slow the car.]
    What do you guys do for break in? This is a forged motor with 11 to 1 CR. for street strip use.

  2. #2
    Administrator RACING JUNKIE bjuice's Avatar
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    Apr 2003
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    Greenville s.c.
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    3,239
    the break in procedure does many things ..seating the rings is one of them.
    i have personally whitnessed brand new motors being dyno tested for the 1st time thru clements racing in Spartanburg S.C. and here is what i saw with my own eye's.

    started up motor brought up to temp oil and water...shut it down. took valave covers off and DID a visual of rockers and valve springs...

    2nd pull- started motor and turned the motor up to 5500 rpm and and let it run motor for abut 2 minutes. (seemed like 2 hrs) it wasn't my motor and i was a nervous wreck..but the guys operating the dyno was cool as a cucumber..they do this a-lot..

    3rd pull --adjusted valves and found the max hp (approx 7200 rpm) on the motor and shut it off..

    4th pull played with timing and carb jetting and pulled the pants off the motor again...fine tuning for HP....I think a total of 9 dyno pulls were performed..but this was fine tunning for max hp..jetting ,timimng,valve adjustments...etc...



    i have started up several new motors on my own..and here is the policy i always follow..

    be sure to prime the motor before starting..make sure you prime just before trying to start..DO NOT prime several days before and let it sit..i made a homemade primer out of an old distributer housing..place a electric drill or a manual speed handle and turn it until you get oil pressure showing on your gage and hold it there for a few minutes..you should feel the TUG agains't the oil pump as it draws up your oil..

    if you have a roller cam you should be fine..but i FEEL ( PERSONAL OPINION) on flatt tappet cams etc with stronger valve springs, to take out the inner valve spring to where there is not much tension on the lifter/cam and after its run at a very,very low rpm..put the inner springs back In...this procedure has been used in the past..improper priming combined with heavy valave spring tension has been the cause of spinning a cam bearing. if this happnes your in trouble...i have seen this happen in person...

    if it were my motor in my shop i would start it as i mentioned above ..let it idle..always have someone looking direclty at your oil gage..NEVER LOOK WAY..if the pressure drops one bit..kill it...

    let the motor idle. check for leaks etc...get the water temp./oil temp up to normal operating temp..then shut it off..take off valve covers and do visual of your rocker arms/valve springs to see if anything is loose or out of place...re-crank and re-peat procedure...then start working up your RPMS......always go back and re-adjust your valves after all of this has been done and the engine is still warm....

    i might have shared too much info but wanted to make sure i covered most of what i knew here..this is a very VITAL part of someones engine process.


    thanks and hope this helps....
    Bjuice..

    "I'M YOUR HUCKLEBERRY ! "

  3. #3
    Senior Member MASTER BUILDER
    Join Date
    Dec 2005
    Location
    Rutherfordton North Carolina
    Posts
    192
    If your engine was torque plate honed and has quality rings there really isn't much breakin necessary.as bjuce said we warm the engine up,ck the valve train and set the valves. by the third pull the rings will be seated and the power stabilized. we then reset the valves and tune the engine. the days of having to take it easy for 500 miles are long gone.Bill
    Hendrens Racing Engines
    1310 U.S. Hwy 221 North
    Rutherfordton N.C. 28139
    828-286-0780 Bill, Steve, Mike
    www.hendrensracingengines.com

  4. #4
    Hey thanks for the info, I have a lot invested and don't want to make any mistakes.

  5. #5
    Senior Member RACING JUNKIE
    Join Date
    May 2006
    Posts
    2,044
    I agree with the others on that the big deal isnt the piston rings sealing up anymore they will be fine if had a good torque plate hone job. However I would recommend doing things alittle differently if you are using a flat tappet cam. Todays oils arent really adequate for flat tappet cams. since the automakers have gone to roller cams and such plus the epa has cracked down on the amount of zinc oil makers can put in conventional oils its a struggle to get these cams broke in correctly, getting the lifters to rotate quickly is of utmost importance or you will roll a lobe and be buying another cam quicker than a cat can lick his ass.
    I would recommend using Rottela t, and adding a can of stp oil treatment they both have high levels of zinc and other anti wear additives. Make sure your cooling system is full, (no air pockets) so you wont have to worry about shutting the engine off for running hot in the first five minutes. I like to take off thermastat housing and fill from there untill full, then install housing and upper hose and fill radiator that way most air is out of motor. Start the motor and run it at between 1500 and 2000 for 20 minutes varying the rpm to properly break in cam
    Heres a link that's a good read on the best oils to use and breaking in a flat tappet cam. Goodluck, Charles

    http://data.melling.com/Tech%20pdfs/...Rev4-12-07.pdf
    ***IN GOD WE TRUST***

  6. #6
    Quote Originally Posted by bjuice
    the break in procedure does many things ..seating the rings is one of them.
    i have personally whitnessed brand new motors being dyno tested for the 1st time thru clements racing in Spartanburg S.C. and here is what i saw with my own eye's.

    started up motor brought up to temp oil and water...shut it down. took valave covers off and DID a visual of rockers and valve springs...

    2nd pull- started motor and turned the motor up to 5500 rpm and and let it run motor for abut 2 minutes. (seemed like 2 hrs) it wasn't my motor and i was a nervous wreck..but the guys operating the dyno was cool as a cucumber..they do this a-lot..

    3rd pull --adjusted valves and found the max hp (approx 7200 rpm) on the motor and shut it off..

    4th pull played with timing and carb jetting and pulled the pants off the motor again...fine tuning for HP....I think a total of 9 dyno pulls were performed..but this was fine tunning for max hp..jetting ,timimng,valve adjustments...etc...
    for what its worth my new engine was done almost identical to this but it hasnt had the fine tuning done as yet because we found problems with the manifold & carbs

    regards
    rod

  7. #7
    Rod, I am waiting for the heads and rotating assemble to come in. I am working on getting the engine out and ready for the build, let me know when you get yours going and we will compare notes, mine is a do it yourself project so it won't be quick. [email protected]


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