At a recent NCRS meet, I had a deduction for excessive lifter noise on my '57 270 HP. I have just adjusted the lifters ot factory specs., .012 on intake and .018 on exhaust. The engine noise still seems to be excessive. Any suggestions? thank
Excessive lifter noise on '57 --270 HP
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Re: Excessive lifter noise on '57 --270 HP
The OEM clearance adjustments are based on a rocker ratio of 1.5:1, but it's really about 1.37:1 at the top of the ramp. Thus at the OEM settings the valve lash is taken up after the end of the constant velocity ramp on opening and on closing the valve is being set down on the seat at greater than ramp velocity. This will increase noise and the rate of valve recession.
Factor the clearnance by 1.37/1.5. and take off a thou, so set them at .010/.016. Follow the shop manual procedure for setting eight at TCS #1 and eight at TDC #6. If this doesn't quite them down then I would question whether you have the correct cam or lifters, or there could be some other mechanical problem with your valve train.
Duke- Top
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Re: Excessive lifter noise on '57 --270 HP
Now there is a far stretch of audacity on the part of an NCRS judge. This guy can tell by listening that the valve lash on a solid lifter cam is too great because the sound level is "too loud"! You can tell this guy has read way too many books and not enough knuckle busting engine work to be a truly competent judge. Tell me, does the judging manual list a specific decibel
level for properly adjusted valves on a 270 hp engine? I suggest a "diplomatic courtesy smile" and ask for a review of his decision by a Team Leader.
BTW: Was the engine cold or had it been warmed? Remember that an early 180 Degrees may not be sufficient heat energy to allow the expansion of the valve train components.
Oh well, the "human element" of NCRS judging! Smile pleasantly and move on in life. Most these guys are pretty decent chaps and will reach out to help a fellow. I would take no specific action relative to the valve noise other that to determine that they are set correctly.- Top
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Excessive lifter noise
1) As another respondent asked, was the engine up to full operating temperature?
2) When adjusting solid valves, bump until one valve is fully opened, then adjust the closed valve. I like to do them at full engine temp, tightened until the gauge slides with about half the resistance needed to "grab & hold" the gauge. I do one head at a time, then re-heat engine & do the other side. I gave up doing them with engine running years ago, too messy no matter how careful you are. Mine run very quietly this way.
3) If you are already doing all the above, I would say the judge is a bit goofy, just smile and walk away.- Top
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Re: Excessive lifter noise on '57 --270 HP
Rex, Others have commented on the judging aspects and I will avoid comment on judging as I am not an NCRS judge or even remotely qualified. If your engine was making a noticable amount of lifter noise well in excess of what other similar cars would produce at idle even by your own observation, I would suspect there might be something wrong with either the cam timing specs, valvetrain condition, or lash setting. Giving the benefit of the doubt to the judge, he may have been correct in his observation of unusual sound from the valvetrain. This is a totaly subjective criteria. Valve trains will make more or less noise depending on how they are adjusted and maintained. Take the deduction experience as a good opportunity to justify a thorough valvetrain condition evaluation. The judge may have sucessfuly pointed out either a maintainence or a technical issue that will require attention before any potential further damage occurs. Too much lash is noisy and will ruin parts. What I am saying is, he may have done you a favor. If it were me, I would be pissed, then check into it thoroughly and save the paperwork on the issue. There will be other opportunities to be judged again.
-Mark.- Top
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Re: Excessive lifter noise on '57 --270 HP
Jack and Dave,
Thank you for your posts. I am the Team Leader for 56/7. our objective as judges is to help the owner EARN his/her award. We are volunteers and travel and spend our own money to attend NCRS events.
I always ask the owners, "What are your objectives with the car?" Did yu do the restoration yourself and how long have you owner the car. Rex's goal was a top flight, he has owned the car since October, some work was done by Rex.
I was the team leader in Orlando, the operations judges called me over to listen to the lifter noise. The engine was up to operating temperature. In our opinion the engine displayed more than a normal amount of lifter noise from the valve covers. Both of the judges and I own solid lifter motors. A minor deduction was
taken for the lifter noise, since the section includes two other items I think the deduction was 6 point or 13/100 of 1 %. The section was reviewed with Rex and he did not seem to have a problem.
I would welcome both of you to attend some NCRS judging events. After twenty-one years of NCRS judging. I continue to learn. Come on out, you would welcome to join our team.
Scott Ssinclair
56/7 Team Leader- Top
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Re: Excessive lifter noise on '57 --270 HP
Scott, I have attended NCRS events for well over a quarter of a century. I have served as a judge for 1956/7 cars as well as 1965's . I began helping to formulate the judging concepts locally prior to the NCRS formation. Objective judging is preferable to subjective judging. When 3 or more judges have to stand around and listen to an engine to determine by its sound some aspect of the internal composition of it's mechanical components then that is clearly a "subjective" evaluation. When one enters the realm of subjective evaluation one must tread lightly. If one is in a situation to error then let that error be in favor of the component being evaluated. "Presumption of innocence with out evidence (objective being better than subjective) to the contrary". Now solid lifters in a hyd. cam motor are easily distinguished. A big rump-rump lopey idle in a 327/300 motor is easily distinguished. But needing 3 judges to listen to a 270hp and then deducting points because the valves clack too loudly is a stretch of judgment which would be easily avoided by simply advising the entrant that "they sound a little loud" but then move forward without taking any punitive action. NCRS judging is a system based on comparisons to a standard. The standard being "as built at the factory" or "as it came out the door". Now consider the gross amount of time spent determining that standard. Now where in that standard does it talk about valve clacking noise? Remember there was no charge about rough idle or a lope which might indicate a higher lift cam. Just the noise of the valves. I give you the wisdom of a man of my years who has sat in judgment of others at functions other than the NCRS. Don't go some place that you can't sustain with solid objective proof. It will come back to bite you! Go easy in life! You see you thought you had reached an understanding with the gentleman in question - yes? And yet here the whole matter appears in print on the page of our organization. Perhaps today you have once again learned something new. The act of judging carries the need for finesse and diplomacy as much as the need of knowledge of the cars. Peace to you Scott, and as a long term member of the NCRS, I say thank you for spending the time, energy and money to assist all those who come to our hobby. You are familiar with the Desiderata? Enjoy.- Top
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Re: Excessive lifter noise on '57 --270 HP
Scott, I have attended NCRS events for well over a quarter of a century. I have served as a judge for 1956/7 cars as well as 1965's . I began helping to formulate the judging concepts locally prior to the NCRS formation. Objective judging is preferable to subjective judging. When 3 or more judges have to stand around and listen to an engine to determine by its sound some aspect of the internal composition of it's mechanical components then that is clearly a "subjective" evaluation. When one enters the realm of subjective evaluation one must tread lightly. If one is in a situation to error then let that error be in favor of the component being evaluated. "Presumption of innocence with out evidence (objective being better than subjective) to the contrary". Now solid lifters in a hyd. cam motor are easily distinguished. A big rump-rump lopey idle in a 327/300 motor is easily distinguished. But needing 3 judges to listen to a 270hp and then deducting points because the valves clack too loudly is a stretch of judgment which would be easily avoided by simply advising the entrant that "they sound a little loud" but then move forward without taking any punitive action. NCRS judging is a system based on comparisons to a standard. The standard being "as built at the factory" or "as it came out the door". Now consider the gross amount of time spent determining that standard. Now where in that standard does it talk about valve clacking noise? Remember there was no charge about rough idle or a lope which might indicate a higher lift cam. Just the noise of the valves. I give you the wisdom of a man of my years who has sat in judgment of others at functions other than the NCRS. Don't go some place that you can't sustain with solid objective proof. It will come back to bite you! Go easy in life! You see you thought you had reached an understanding with the gentleman in question - yes? And yet here the whole matter appears in print on the page of our organization. Perhaps today you have once again learned something new. The act of judging carries the need for finesse and diplomacy as much as the need of knowledge of the cars. Peace to you Scott, and as a long term member of the NCRS, I say thank you for spending the time, energy and money to assist all those who come to our hobby. You are familiar with the Desiderata? Enjoy.- Top
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