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Discussion Starter · #1 ·
I haven't put many hours on my new motor, but I though after I run it this weekend I'd check at least some of the valves. Motor in this case is a bbc with a bullett solid roller. I guess my main question is the cam card says "hot" lash is .020 intake, .026 exaust. So would those #'s be the same with iron or aluminum heads?? I don't know why that sounds loose to me. I guess when the motor is cold those lash #'s will be smaller/tighter?
 

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E-7 Sheepdog (ret)
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The lash "hot" is with the engine warmed up. Set them that way and don't worry about what they are cold.

HOT, yes, those numbers will be the same regardless of block or head material, becasue they are at operating temperature, fully expanded.

The gaps will shrink a certain ammount as the iron block and heads cool, it will shrink a lot more with Aluminum heads since Aluminum changes size aprox 2x as much as iron does over the same temperature range.
 

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Discussion Starter · #5 ·
The lash "hot" is with the engine warmed up. Set them that way and don't worry about what they are cold.

HOT, yes, those numbers will be the same regardless of block or head material, becasue they are at operating temperature, fully expanded.

The gaps will shrink a certain ammount as the iron block and heads cool, it will shrink a lot more with Aluminum heads since Aluminum changes size aprox 2x as much as iron does over the same temperature range.
So the #'s outlaw put up are a gustimate of cold set #'s. Set them hot at what the card says then.....gotcha. Edit; I guess it would have helped if I'd have clicked on his link....duh.
 

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That would be correct. If you want to know what your combo is expanding measure it cold, write it down, then hot, write it down. I'm running an aluminum block and heads, and on average, it grows .013. Cold lashing will get you in the ballpark, hot lashing will get you on the money. If you haven't done alot of this, here's a few tips. Rig up a 5 gallon bucket of water to recirculate through your boat, I like to reach 180 degree's or higher. You can allow the motor about 5 to10 minates to cool so the headers don't burn you...much. Just enough to where you can deal with the header heat, it won't have any big impact on accuracy. If you don't allready have one, get a remote starter switch, it will make life much easier. I like to start on one head left to right, one cylinder at a time, adjust Intake as exh. begins to open, adjust Exhaust as int. is almost fully closed. Write that sequence down on a small piece of paper, stick it to your scoop. You want a very solid drag on your feeler gauge, it should not go in and out easy, but with a mild resistance. If your feeler gauge goes in and out easy, than you are beyond that number. Don't get super crazy about having to get it to the exact thousandth. That is what you are striving for, but as a novice realize one or two thousandths either way is not going to hurt your motor. One dyno trick is to make pulls tightening or loosening the lash to let you know if the motor wants more or less cam. Have fun, it's theraputic! F1~;)
 

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Discussion Starter · #7 ·
Thanks for the reminder on the valve adjustment, I'm going to try that method around this time. As far as the the hot cold #'s, I was going to take it to the lake and run it all afternoon,then take the #'s on a couple of cylinders,then meas the difference when it's cold. I don't know, she seems a little noisy to me,but I've never had a solid cam before(flat or roller). I did kind of assume that if they were too loose,that it would be bad for the lifters and lobes. Sounds like maybe not so much...
 

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steelcomp was here
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Thanks for the reminder on the valve adjustment, I'm going to try that method around this time. As far as the the hot cold #'s, I was going to take it to the lake and run it all afternoon,then take the #'s on a couple of cylinders,then meas the difference when it's cold. I don't know, she seems a little noisy to me,but I've never had a solid cam before(flat or roller). I did kind of assume that if they were too loose,that it would be bad for the lifters and lobes. Sounds like maybe not so much...
Lose valve train can beat up rockers and valves and cause destructive harmonics, and is definitely not a good thing.
 

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Your gonna get valvetrain noise from a solid, be it flat tappet or roller. The only way your going to get away from the noise is going hydraulic. Just because you hear it is no alarm that it is off, but it is good to double check. And .020 and .026 are not loose numbers, very standard. I'm currently running my chit at .024 I, .026 E. :) Taking breaks from sanding my floor.....

P.S. Higher quality motors deserve higher quality oils. The noise will let up a little running higher quality oils. I've been running Valvoline VR1 for a while now, and am real happy with it, but a friend is trying to get me into full synthetics such as Redline. Alot of debate on exactly what viscosity is best, I won't advise there, but I would try and push you into higher quality oils if you are not currently using them, F1~
 

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Cantard
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Your gonna get valvetrain noise from a solid, be it flat tappet or roller. The only way your going to get away from the noise is going hydraulic. Just because you hear it is no alarm that it is off, but it is good to double check. And .020 and .026 are not loose numbers, very standard. I'm currently running my chit at .024 I, .026 E. :) Taking breaks from sanding my floor.....

P.S. Higher quality motors deserve higher quality oils. The noise will let up a little running higher quality oils. I've been running Valvoline VR1 for a while now, and am real happy with it, but a friend is trying to get me into full synthetics such as Redline. Alot of debate on exactly what viscosity is best, I won't advise there, but I would try and push you into higher quality oils if you are not currently using them, F1~
I just steped up to redline 10-40 in the new motor. Should have feedback soon. What oil are you running Kreg? (h20)
 

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Cantard
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sorry Kreg I should have said this was a good starting point for first assembly. this will get you close for startup, after you set them HOT
you can check them cold for future reference.
:)devil After setting them hot I do a cold run and write every reading down.....makes it easy for random checks later on. Something moves you,ll know....caught a roller going south once, now I am not so lazy on checking....saved the cam...no harm done.
 

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What the Hell is That?
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Not to Hi jack this thread but my motor 327 solid cam, solid lifters, has a valve lash setting of .015 for Intake and exhaust. I find that a little strange. Is this common or is my old man full of him self?
 

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steelcomp was here
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Not to Hi jack this thread but my motor 327 solid cam, solid lifters, has a valve lash setting of .015 for Intake and exhaust. I find that a little strange. Is this common or is my old man full of him self?
Nothing wrong with that. I'd rather run .015 than .024
 

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Discussion Starter · #16 ·
How loose is too loose??

Nothing wrong with that. I'd rather run .015 than .024
Like I said earlier...026 sounds way loose to me. Should I set them at that because the card says too???.....or??? And why would the exhaust be set looser that the intake? Sorry for all the dumb questions....just checked em cold and the intakes are looking about .014-.013, and most of the exhausts are .021-.023(cold). Are the exhaust valves going to grow because they're hot??..therefore set looser?
 

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steelcomp was here
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Like I said earlier...026 sounds way loose to me. Should I set them at that because the card says too???.....or??? And why would the exhaust be set looser that the intake? Sorry for all the dumb questions....just checked em cold and the intakes are looking about .014-.013, and most of the exhausts are .021-.023(cold). Are the exhaust valves going to grow because they're hot??..therefore set looser?
Not stupid questions at all, and yes, the ex. are typically set a little wider because they'll grow more. For lash, I usually start with what the card says, but seldom end up there. I don't understand the big lash numbers on some cams, but then again, I don't understand a lot of things.:p
 

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my current cam card on my lunati solid roller says 24/26 in my 565 and my street roller cam card is 30/30 cam # 50200 that i run in my 496 engines.
is the difference in cyl pressure? more lash will pick up cyl pressure but you would think .030/.030 would be hard on valve train.
dont some lobe ramps need the larger lash to function correctly?
 

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My isky solid is suposed to be .028 hot. I set it cold at .020 cold with my brodix heads. It gains .006 to .008 with the alunimum heads on my motor. I think next time i'll set the exhaust at .018 and the intakes at .016 cold and then check them hot.
 
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