Lash adjustment
07-21-2009, 12:59 AM
#11
Senior Member
RACING JUNKIE
Join Date: May 2006
Posts: 2,044
Originally Posted by TheRabbit
A good valve train SHOULD NOT MOVE. IF IT DOES SOMETHING IS WRONG!!! Take notes which ones you have to adjust and which way. If you have to keep getting tighter you probably have a seat problem. Bottom line is if you have to adjust the same ones next time look at everything really close!!
Good point Rabbit, I like the idea of taking notes too - good info.
Cp
07-21-2009, 05:15 AM
#12
Member
MASTER JOURNEYMAN
Thread Starter
Join Date: Feb 2008
Posts: 45
Fellow Motorheads thank you very much for the provided info,based on the fact you all recommend between .oo4-.006 i'm going to split the difference and go with .005. The keeping of records makes perfect sense,as i work in the metal fab industy i make go/no go gauges on a regular basis and will make a set specific to the task at hand. As for valve train stability i'll be using a Jesel shaft rocker system for the first time that some of you previously indicated would be well up to the task of maintaining the desired stability. As this engine is in a daily driver with full exhaust and no stereo i should have little trouble identifying any changes in valve train noise if any thing starts going south. Again Thank You for all the input.
07-21-2009, 08:54 AM
#13
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RACING JUNKIE
Join Date: Jan 2007
Location: Augusta, Ga.
Posts: 2,276
Not to ramble on, but I use to be obsessed with valve lash. I'd adjust after every race. I'd always find one or two that just seem exactly right. I use to take the tempeture of the rockers before I adjusted 'em. If it wasn't 180* I'd crank it up and get the temp up. Took me all day to set the lash 
ops:. I worried about it to the point of talking to 4 of 5 different engine builders about hot vs cold, .022 tight fit, snug fit, loose fit and so on.
I'm finally at peace with my lash now that I do it Cold and Snug!! LOL.
THANKS TO STEVE VANCE FOR HELPING ME THROUGH THAT!
!
Also remember a small cam or lazy cam likes more lash. Bigger cams, more aggressive cams like tighter lash :wink:
ops:. I worried about it to the point of talking to 4 of 5 different engine builders about hot vs cold, .022 tight fit, snug fit, loose fit and so on. I'm finally at peace with my lash now that I do it Cold and Snug!! LOL.
THANKS TO STEVE VANCE FOR HELPING ME THROUGH THAT!
!Also remember a small cam or lazy cam likes more lash. Bigger cams, more aggressive cams like tighter lash :wink:
07-21-2009, 01:03 PM
#15
Senior Member
RACING JUNKIE
Join Date: Jan 2007
Location: Augusta, Ga.
Posts: 2,276
I don't think so. The tighter lash does make the cam seem a little bigger, but don't go overboard with that either. Of course the more you drive it the more you will need to check it. Just don't do like I did and overthink it or do it to much. Jesel are good rockers and you shouldn't have any problems or very much movement. My suggestion would be to get them all the same as the spec sheet says HOT (may take a few times to get all of 'em right) then find whatever feeler guage fits that setting when it's cold and use that from then on. Just remember if you error, error on the tight side and I mean from snug to firm, not snug to tight and you'll be ok.
07-23-2009, 06:12 PM
#17
Junior Member
SHOW GUEST
Join Date: May 2006
Posts: 4
You can take the "hot" setting given to you in the catalog or cam specification card and alter it by the following amount to get a "cold" lash setting.
With iron block and iron heads, add .002"
With iron block and aluminum heads, subtract .006".
With both aluminum block and heads, subtract .012".
Remember this correction adjustment is approximate and is only meant to get you close for the initial start up of the engine. After the engine is warmed up to its proper operating temperature range, you must go back and reset all the valves to the proper "hot" valve lash settings.
With iron block and iron heads, add .002"
With iron block and aluminum heads, subtract .006".
With both aluminum block and heads, subtract .012".
Remember this correction adjustment is approximate and is only meant to get you close for the initial start up of the engine. After the engine is warmed up to its proper operating temperature range, you must go back and reset all the valves to the proper "hot" valve lash settings.
