Re: Best way to check valve lash.....
[Re: ragingram]
#779262
08/20/10 11:36 PM
08/20/10 11:36 PM
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Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer
master
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master
Joined: Nov 2003
Posts: 6,293
Rock Springs
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I see this asked often and dont understand it...Sorry. What is the engine, and heads...we can get you real close if your provide what hot lash thats written on the cam card. Set the lash we recommend, warm the engine up to operating temp, and pull of one valve cover and verify what hot lash is... No need to get burnt, if its spot on, dont worry about it, if its off in one way or another, let it cool and do the math and make the according changes. I built a engine for a guy locally that wanted a solid roller cam and power, but was to lazy to do the extra work to check things out intially, and check up on it every once in awhile... But he didnt want to pay me, or anyone else to lash the valve either, he thought i could drop what I was doing and do this when ever just for fun.. I didnt want to throw in a whomper cam set it up, have him never check it out, then later its needs attention and the engine eats it self up eventually.... Then have him go and say...well Bob Coomer builds crap engines..which they will say guaranteed. Long story short he received a hyd flat tappet in a engine I know would have made close to 50hp+ more hp with a custom roller. My advice to him is if he doesnt feel like the little things as pulling a valve cover and looking around on the weekend...He doesnt need to be racing  Im sorry I got off track here, Im not in anyway saying your anything like this guys, so dont take me the wrong way......but if your are...Im truly sorry LOL  Post up what your working on and these guys will get you close 
[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
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Re: Best way to check valve lash.....
[Re: Bob_Coomer]
#779263
08/21/10 12:45 AM
08/21/10 12:45 AM
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Joined: Aug 2008
Posts: 78
Canada/USA
ragingram
OP
member
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OP
member
Joined: Aug 2008
Posts: 78
Canada/USA
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Sorry i was not thinking when i posted.. should have gave the specs. Engine is 622ci with B1-TS heads. 1200hp Cam is LSM 60mm Card does not give hot lash... But engine builder said .010 cold Cam is .525In .520ex 1.8 rockers Duration: 286in 312ex LCA 116 Overlap 67 fire order 1-8-7-3-6-5-4-2 We have the Valve covers off after every run checking lash. Oil is changed every 2-3 runs with running alcohol. Plugs changed every run. So far i have been checking it by when the opposite valve is all the way down (or just coming back up) i check the other one to the same cylinder. Not sure this is the best way to do it.... We are not the ones to sit back and let a engine hurt itself  But my method of doing this lash stuff seems to take for ever. there must be a simpler way.
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Re: Best way to check valve lash.....
[Re: Bob_Coomer]
#779264
08/21/10 01:24 AM
08/21/10 01:24 AM
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Joined: Jul 2010
Posts: 3,502
SOUTH JERSEY
HEMIFRED
master
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master
Joined: Jul 2010
Posts: 3,502
SOUTH JERSEY
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100% fool proof method of setting valve lash. I do it cold . then again after it's hot to see how much it has changed.
I only do it hot once. that way I know how much wider it gets due to the heat.
Roll the engine over until #1 Exhaust just starts to open- this insures you are on the front side of the lobe, NOT the overlap side, thereby insuring the intake is not open. At this point, you will adjust the intake lash on that cylinder.
Once you have adjusted the intake lash turn the engine until the exhaust opens all the way and closes, and the intake opens and is very nearly closed again. This insures you are on the back side of the intake lobe and the exhaust must be fully closed. The reason for stopping just shy of the intake fully closing is to make sure you don’t go too far and pass thru the both valves closed area and start back opening the exhaust. Adjust the Exhaust valve now.
home of the
Sox and Martin Hemi Duster
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Re: Best way to check valve lash.....
[Re: Cab_Burge]
#779267
08/21/10 08:39 AM
08/21/10 08:39 AM
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Joined: Jan 2003
Posts: 2,937
A shed in England
Tig
master
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master
Joined: Jan 2003
Posts: 2,937
A shed in England
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We turn the motor over 'till the valve we want to check is fully open, take a note of the position of the engine (degree's on the damper using the timing pointer) and turn over one full turn. That way we know the lifter is 180 degrees after full lobe lift (opposite) and on the base circle of the cam. One thing thats not been mentioned here is base circle run out. This is the way we set ours, takes a bit of time. We set the lash cold btw, -12 thou from what the cam card suggests (ie 18 thou for a 30 thou hot lash) It has alloy heads and block. Then check it warm. Everyone has there own technique, if it works, non of them are wrong 
'74 Challenger..9.46 @ 145.9 1/4, 6.001 @ 118 1/8 so far. 4023lb !!! # N/A, Marsh performance 655ci, Indy Maxx, T/R, Indy 600-13 X's, Street legal, pump gas, full interior, Cal-Tracs, mufflers, 3:73's and real 10.5 radials.
9.51 @ 142.4 1/4, 6.003 @ 114 1/8 with our old mule KB, 572-13, 580 wedge.
RHD '68 Barracuda Fastback 323ci street/strip. Best ET 13.88 @ 99.03
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Re: Best way to check valve lash.....
[Re: AAR-B4]
#779269
08/21/10 09:26 AM
08/21/10 09:26 AM
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Joined: Feb 2007
Posts: 6,295
U.S.
moparniac
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master
Joined: Feb 2007
Posts: 6,295
U.S.
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my aluminum block head combo the lash grows .012... I set them .008 cold and hot it checks out to .020 which the cam calls for... I set lash the old fashioned way by the chart!
Mopar Performance
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Re: Best way to check valve lash.....
[Re: ragingram]
#779273
08/21/10 04:18 PM
08/21/10 04:18 PM
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Joined: Jan 2003
Posts: 5,992
Anoka County, MN
Leigh
master
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master
Joined: Jan 2003
Posts: 5,992
Anoka County, MN
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Quote:
Sorry i was not thinking when i posted.. should have gave the specs.
Engine is 622ci with B1-TS heads. 1200hp
Cam is LSM 60mm
Card does not give hot lash... But engine builder said .010 cold
Cam is .525In .520ex 1.8 rockers
Duration: 286in 312ex
LCA 116
Overlap 67
fire order 1-8-7-3-6-5-4-2
We have the Valve covers off after every run checking lash. Oil is changed every 2-3 runs with running alcohol. Plugs changed every run.
So far i have been checking it by when the opposite valve is all the way down (or just coming back up) i check the other one to the same cylinder.
Not sure this is the best way to do it....
We are not the ones to sit back and let a engine hurt itself But my method of doing this lash stuff seems to take for ever. there must be a simpler way.
Sounds like one mean mother. NICE engine
Here is the page from Crane
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Re: Best way to check valve lash.....
[Re: Thumperdart]
#779274
08/21/10 07:22 PM
08/21/10 07:22 PM
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Joined: Jan 2007
Posts: 3,695
nc
emarine01
master
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master
Joined: Jan 2007
Posts: 3,695
nc
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Quote:
Quote:
100% fool proof method of setting valve lash. I do it cold . then again after it's hot to see how much it has changed.
I only do it hot once. that way I know how much wider it gets due to the heat.
Roll the engine over until #1 Exhaust just starts to open- this insures you are on the front side of the lobe, NOT the overlap side, thereby insuring the intake is not open. At this point, you will adjust the intake lash on that cylinder.
Once you have adjusted the intake lash turn the engine until the exhaust opens all the way and closes, and the intake opens and is very nearly closed again. This insures you are on the back side of the intake lobe and the exhaust must be fully closed. The reason for stopping just shy of the intake fully closing is to make sure you don’t go too far and pass thru the both valves closed area and start back opening the exhaust. Adjust the Exhaust valve now.
I tried every method on my Isky solid roller and this method was close EXCEPT after adjusting the in. I rolled it over till the in. was fully open then JUST starting to close and then adjusted the ex. I measured every inch of each lobe and this was the loosest point. 
 One of the Crane solid rollers I had to be set like that also
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