Valve Lash?

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Ricks70Duster340

Ricks70Duster340

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I have a 440 (512 stroker) with Trickflow heads, Harland Sharp rockers, and a solid roller cam. The cam card said to set the valve clearance to .018 for both intake & exhaust which I've done. There seems to be too much clearance because the top of the engine is noisy. Years ago I could always tell when an older slant 6 car was next to me at a stop light because I could hear the clattering. This is not that bad but it seems to be noisier than it should be. Is there a trick to setting the clearance that is not too tight but get rid of the excess?
 
For cold clearances, try tightening it up about .004 or .005 or so to account for the additional heat expansion of the aluminum heads.
Or get the hot specs and set them after the engine is at operating temp.
 
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did the cam card say cold? most engine with steel block and alum heads you set lash .006 tighter than cam card says, I've checked this after the motor is hot and it's spot on.
 
Aluminum rocker arms and fabricated valve covers are noisy in general. I agree with setting the lash at operating temperature or compensating by setting them tight when it is cold.
 
Ricks70Duster340 said:
It is an Oregon cam and they are 1.6
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Why don’t you send Ken an email or see if you can get a hold of him on the phone. My interactions with him have been pretty good and he seems willing to answer my questions. I do this before messing with the clearances that he specified.
 
I would doubt a cam grinder would quote cold clearances, because the final operating clearance will depend on various engine components...which the cam grinder has no control over. If the clearance on the card does say cold, then that is bad practice for the reasons stated. Also, unless the stated lash specifically states for 1.6 rockers, the lash would be for 1.5 rockers. For 1.6 rockers, the lash should be increased 0.015 -0.002".
 
Set lash cold, warm the motor to operating temp, pull a cover, and see where the lash went.
Reset cold, using the change from cold to hot, to reach correct hot clearance. Example: set to .015 cold, warm it's at .020. You want .015 warm, so set cold to .010 .
 
Thanks to all of you for the replies. I got an education! I emailed Ken at Oregon Cams and this is what he said:

"You need to make your final valve lash adjustment with the engine hot. If you want a cold setting to start with I would adjust them about .006”/.007” tight with the aluminum head and it will be close enough to start the engine, then warm up the engine to do a hot setting. If you set them at .018 cold they will be about .024” hot but again you need to do the final adjustment at .018” with the engine hot."
 
Solids always have sounded noisey, love that sound, just like a Singer sewing machine. You mean that you can hear them over your loud mufflers?
 
Professor Fate said:
For cold clearances, try tightening it up about .004 or .005 or so to account for the additional heat expansion of the aluminum heads.
Or get the hot specs and set them after the engine is at operating temp.
Click to expand...
,006 for alum. heads on a cast iron block (cold) , been doing mine that way for about 12-13 yrs/solid roller, 1/6 rockers...jfyi
 
famous bob said:
,006 for alum. heads on a cast iron block (cold) , been doing mine that way for about 12-13 yrs/solid roller, 1/6 rockers...jfyi
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Reset the valves cold to .012 (.006 less than the cam card .018 specified), then got the engine hot and rechecked. All at .018 now and the engine purrs along. Yay!
 
Ricks70Duster340 said:
Thanks to all of you for the replies. I got an education! I emailed Ken at Oregon Cams and this is what he said:

"You need to make your final valve lash adjustment with the engine hot. If you want a cold setting to start with I would adjust them about .006”/.007” tight with the aluminum head and it will be close enough to start the engine, then warm up the engine to do a hot setting. If you set them at .018 cold they will be about .024” hot but again you need to do the final adjustment at .018” with the engine hot."
Click to expand...

my cam specs say .016 intake , .018 exhaust , I have set them all at .010 cold the last 2 times , and did recheck a few valves after hot , they were pretty much right on , never worried about it after that ...and it does make a fair amount of lifter noise , all the solid rollers I`ve had did ..hemi , 2 -406 SBC , and now the 505...
 
I think Chry V8s using shaft rockers & alum heads should have the lash set 0.001-0.002" less than stud mount rockers because of the alum shaft mounts v a steel rocker stud engine.
 
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