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Re: VALVE LASH ADJUSTMENT
[Re: moparmacka]
#1856505
06/25/15 11:35 AM
06/25/15 11:35 AM
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Joined: Sep 2014
Posts: 4,457
Washington
madscientist
master
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master
Joined: Sep 2014
Posts: 4,457
Washington
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You can use the old mopar decal procedure on any 1-8-4-3-6-5-7-2 firing order. If you have a 4-7 swap (or omore swapped cylinder) firing orders just adjust the order that is on the decal to reflect the new firing order.
For a .020 HOT lash setting with a CI block and aluminum heads you need to be .004-.006 LESS COLD to START with. Get the engine to operating temp and check you HOT setting against the COLD setting until you get the .020 that Crane wants. For example, if you set the valves at .016 COLD and with the engine to temp they check at .024 HOT, you should understand that your COLD setting should be adjusted to .010 and again, you would want to start out with the setting dead cold and warm it up and re-check the HOT lash.
If you have a CI block and CI heads, I try to set them cold .002 LESS than HOT lash and warm up and check.
For those of you with the Midas touch and have aluminum blocks and heads you start COLD lash .010-.012 LESS than the HOT setting and warm up and check.
FWIW the cam card lash settings are suggestions. Most of the time if you test you will find out that lash can be set tighter than what the card says and performance will improve, especially cams that call out for .028-.032 HOT settings. I usually end up at .020 or so on those with much improved performance.
I NEVER set lash any wider than the cam card says HOT. If you loosen the lash and the engine is happy you need another cam.
My .000169 cents (adjusted for 2015 inflation).
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: VALVE LASH ADJUSTMENT
[Re: moparmacka]
#1856522
06/25/15 12:02 PM
06/25/15 12:02 PM
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Joined: Nov 2004
Posts: 6,890
North Alabama
Monte_Smith
master
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master
Joined: Nov 2004
Posts: 6,890
North Alabama
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The mopar chart is likely fine, if you have an old school 60s grind, when that chart was made, if you don't, I wouldn't use it and personally, I NEVER use it anyway. The ONLY proper way to adjust valves is with the lifter on the heel of the lobe. To make SURE that is the case, use the tried and true ex opening and intake closing method. This is NEVER wrong
Monte
Last edited by Monte_Smith; 06/25/15 12:02 PM.
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Re: VALVE LASH ADJUSTMENT
[Re: Thumperdart]
#1856578
06/25/15 01:12 PM
06/25/15 01:12 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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I use the open/closed method also  Same here but recently found .004 by slightly rotating engine over more so what`s your method Mike...................  Mine doesnt do that... when its on the heal thats it.. I have rolled it back and forth to check
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Re: VALVE LASH ADJUSTMENT
[Re: Thumperdart]
#1856621
06/25/15 01:48 PM
06/25/15 01:48 PM
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Joined: Nov 2004
Posts: 6,890
North Alabama
Monte_Smith
master
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master
Joined: Nov 2004
Posts: 6,890
North Alabama
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I use the open/closed method also Same here but recently found .004 by slightly rotating engine over more so what`s your method Mike................... No matter how open, or how closed, you are STILL using THAT method, in lieu of some "chart". Cam timing as you have seen, can vary how much open or how much closed, as to where you need to adjust, but it still remains that ON THE HEEL is the only RIGHT way to do it. So how do you know where the TRUE heel is?.........simple, you LOOK, when you install cam. You are going to have the intake off, whether it is in the car or not. So after the cam is installed and degreed, you roll motor until cam is clearly on heel and see where the valves are in relation to open and closed. THIS is the RIGHT place to adjust it. So where is "TRUE" heel........again simple. Its 180* from the top of the lobe. This is true for ANY cam and ANY cam timing Monte
Last edited by Monte_Smith; 06/25/15 01:54 PM.
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Re: VALVE LASH ADJUSTMENT
[Re: Monte_Smith]
#1856633
06/25/15 02:01 PM
06/25/15 02:01 PM
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Joined: Jul 2004
Posts: 19,318
State of confusion
Thumperdart
I Live Here
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I Live Here
Joined: Jul 2004
Posts: 19,318
State of confusion
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I agree it`s best w/intake off and I THOUGHT I had it figured it out but apparently just a bit off.
72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....
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Re: VALVE LASH ADJUSTMENT
[Re: Monte_Smith]
#1856897
06/25/15 07:17 PM
06/25/15 07:17 PM
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Joined: Jan 2003
Posts: 25,988
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,988
Rio Linda, CA
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The ONLY proper way to adjust valves is with the lifter on the heel of the lobe. Heel or base circle? Heel is one distinct spot, base circle spans many degrees.
The INTERNET, the MISinformation superhighway
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Re: VALVE LASH ADJUSTMENT
[Re: John_Kunkel]
#1856964
06/25/15 08:32 PM
06/25/15 08:32 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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The ONLY proper way to adjust valves is with the lifter on the heel of the lobe. Heel or base circle? Heel is one distinct spot, base circle spans many degrees. Base
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Re: VALVE LASH ADJUSTMENT
[Re: John_Kunkel]
#1857146
06/25/15 11:34 PM
06/25/15 11:34 PM
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Joined: Nov 2004
Posts: 6,890
North Alabama
Monte_Smith
master
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master
Joined: Nov 2004
Posts: 6,890
North Alabama
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The ONLY proper way to adjust valves is with the lifter on the heel of the lobe. Heel or base circle? Heel is one distinct spot, base circle spans many degrees. This has been discussed before and the answer is that it depends on how the lobe is shaped, but you can usually say the heel is on the base circle
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Re: VALVE LASH ADJUSTMENT
[Re: moparmacka]
#1857289
06/26/15 10:20 AM
06/26/15 10:20 AM
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Joined: Nov 2006
Posts: 370
Queensland Australia
moparmacka
OP
enthusiast
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OP
enthusiast
Joined: Nov 2006
Posts: 370
Queensland Australia
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Cheers.
Monte, you find max lift then rotate 180 degrees.
I tried a Cranes recommendation today. Sounds a little weird almost closed and just opening!
Last edited by moparmacka; 06/26/15 10:21 AM.
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Re: VALVE LASH ADJUSTMENT
[Re: madscientist]
#1857362
06/26/15 12:52 PM
06/26/15 12:52 PM
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Joined: Oct 2003
Posts: 7,506
Az
Crizila
master
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master
Joined: Oct 2003
Posts: 7,506
Az
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You can use the old mopar decal procedure on any 1-8-4-3-6-5-7-2 firing order. If you have a 4-7 swap (or omore swapped cylinder) firing orders just adjust the order that is on the decal to reflect the new firing order.
For a .020 HOT lash setting with a CI block and aluminum heads you need to be .004-.006 LESS COLD to START with. Get the engine to operating temp and check you HOT setting against the COLD setting until you get the .020 that Crane wants. For example, if you set the valves at .016 COLD and with the engine to temp they check at .024 HOT, you should understand that your COLD setting should be adjusted to .010 and again, you would want to start out with the setting dead cold and warm it up and re-check the HOT lash.
If you have a CI block and CI heads, I try to set them cold .002 LESS than HOT lash and warm up and check.
For those of you with the Midas touch and have aluminum blocks and heads you start COLD lash .010-.012 LESS than the HOT setting and warm up and check.
FWIW the cam card lash settings are suggestions. Most of the time if you test you will find out that lash can be set tighter than what the card says and performance will improve, especially cams that call out for .028-.032 HOT settings. I usually end up at .020 or so on those with much improved performance.
I NEVER set lash any wider than the cam card says HOT. If you loosen the lash and the engine is happy you need another cam.
My .000169 cents (adjusted for 2015 inflation). My Comp Cams cam card does not give a hot / cold setting. It just gives a setting ( .012 / .012 ). Assume they are looking at cold? I have used all the adjusting methods listed and they all work equally well IMO - as long as you stay out of the ramp area. Picking a cam is always a compromise. Running tighter lash than recommended, although giving you more lift and duration, doesn't always equate to improved performance. Within limits, changing lash is a good way to dial in your cam if you are in the ball park to start with. With todays lift rates, you sure don't want to run off the ramp area of the lobe ( on ether side ).
Fastest 300
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Re: VALVE LASH ADJUSTMENT
[Re: moparmacka]
#1857428
06/26/15 03:02 PM
06/26/15 03:02 PM
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Joined: Aug 2003
Posts: 43,303
Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,303
Bend,OR USA
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Cheers.
Monte, you find max lift then rotate 180 degrees.
I tried a Cranes recommendation today. Sounds a little weird almost closed and just opening! Don't forget that the cam rotates half as fast as the crankshafts does so when the intake lobes is at max lift at say 110 ATDC the motor will need to rotate 360 degrees to get the cam lobes positioned exactly opposite of where it was on the intake stroke at 110 ATDC   If you rotate the crank 180 from max lift(1/2 of 180 equals 90 cam degrees) it may still have the valves opened or be on the closing ramps on a big duration cam
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: VALVE LASH ADJUSTMENT
[Re: Monte_Smith]
#1857567
06/26/15 06:42 PM
06/26/15 06:42 PM
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Joined: Jan 2003
Posts: 25,988
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,988
Rio Linda, CA
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This has been discussed before and the answer is that it depends on how the lobe is shaped, but you can usually say the heel is on the base circle Regardless of lobe "shape", the base circle is the base circle and it is equidistant from the rotational center of the lobe. Since the base circle is comprised of several degrees of cam rotation, proper lash can be measured anywhere on the base circle; so this nonsense that the valve lash must be adjusted on the precise heel (180° from max lift) is just that...nonsense.
The INTERNET, the MISinformation superhighway
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Re: VALVE LASH ADJUSTMENT
[Re: moparmacka]
#1857613
06/26/15 07:50 PM
06/26/15 07:50 PM
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Joined: Jan 2003
Posts: 10,019
Frostbitefalls MN (Rocky&Bullw...
gregsdart
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 10,019
Frostbitefalls MN (Rocky&Bullw...
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On the most radical cam lobes, you would still have about half the lobe being base circle. That leaves a ton of room for small variables. The Mopar two valve per 90 degrees will put the valve being set with the lobe being very close to the heel. How close? Take the installed centerline for either intake or exhaust, what ever you are setting, subtract 90 degrees from the installed CL, divide by two because we are talking CAM degrees, which are half crank degrees. A 112 lsa in at 112 would be 112-90= 22, divided by two, you get 11 degrees of the cam lobe from the exact center of the heel. I seriously doubt anyone can be within 11 degrees on all 16 valves just by watching the valve motion. I have trouble getting within 10 crank degrees due to fighting compression forces, and I am looking at the degreed damper. Either the two valve per 90, or watching where the adjacent valve is as you bump the motor around will work just fine IMHO. Either will get you within a few degrees of the exact center of the lobe heel.
Last edited by gregsdart; 06/26/15 07:54 PM.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky
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Re: VALVE LASH ADJUSTMENT
[Re: John_Kunkel]
#1857675
06/26/15 08:47 PM
06/26/15 08:47 PM
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Joined: Nov 2004
Posts: 6,890
North Alabama
Monte_Smith
master
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master
Joined: Nov 2004
Posts: 6,890
North Alabama
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This has been discussed before and the answer is that it depends on how the lobe is shaped, but you can usually say the heel is on the base circle Regardless of lobe "shape", the base circle is the base circle and it is equidistant from the rotational center of the lobe. Since the base circle is comprised of several degrees of cam rotation, proper lash can be measured anywhere on the base circle; so this nonsense that the valve lash must be adjusted on the precise heel (180° from max lift) is just that...nonsense. Jeez dude, what is your problem, you said this same stuff last time this was brought up. Some cams, depending on flat tappet, roller, hydraulic lobes have different shapes. The amount of degrees on the base circle is NOT THE SAME ON EVERY CAM MADE. Hence my suggestion to adjust it on the heel, because then you KNOW for a fact you are on the base circle. Why is that nonsense............please explain. Just like Dom said.............he was using some "method" he thought was right and was on the base circle. It wasn't, he rolled it a little more and the lash loosened .004. If he had put it on the HEEL to start with he would have no doubt been on the base circle........correct?.......So explain the "nonsense" part of my suggestion again
Last edited by Monte_Smith; 06/26/15 08:53 PM.
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Re: VALVE LASH ADJUSTMENT
[Re: Monte_Smith]
#1857733
06/26/15 10:13 PM
06/26/15 10:13 PM
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Joined: Jul 2004
Posts: 19,318
State of confusion
Thumperdart
I Live Here
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I Live Here
Joined: Jul 2004
Posts: 19,318
State of confusion
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Hey, I really "Swore" it was perfect my old way and decided to check it again and guess what? I was wrong even though I "thought" for sure it was perfect but this time I measured every square in. of each lobe and got my .004 back.
72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....
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