Slant Six Forum :: Fun with Valve Lash

I was shipped a RV cam for hydraulic lifters. Well I have solid lifters and my order was quite specific as to what cam I needed. I called the mfgr, and there grinder said "no problem, just set your lash at 8 and 12, not 10 and 20".

Am I being BS'd to avoid a new cam free to me

Nice thread y'all!
I was reviewing invoices for parts for a rebuild I just finished. I saw I was shipped a RV cam for hydraulic lifters. Well I have solid lifters and my order was quite specific as to what cam I needed. I called the mfgr, and there grinder said "no problem, just set your lash at 8 and 12, not 10 and 20"...
rock
64d100

LOBE SEPARATION ANGLE: This is the relationship between the centerlines of the intake and exhaust lobes. A 110-degree lobe separation angle means that the peak opening points of the intake and exhaust lobes are 110 degrees apart. This is ground into the cam and canâ€™t be changed without changing cams. Lobe separation angle is another way of expressing overlap, which is the term formerly used by cam manufacturers. Overlap is the amount of time that both valves are open in the same cylinder. When both valves are open at the same time, cylinder pressure drops. A cam with 106 degrees of lobe separation angle will have more overlap and a rougher idle than one with 112 degrees, but itâ€™ll usually make more midrange power.

How does one go about determining the proper valve lash for a given camshaft?

I was pretty shocked and bummed out to contemplate tearing down a just-finished engine...a task I may not do now, thanks to DD.

[

Think carefully...remember, DD also said this combination would probably wear faster. You paid for a specific cam; you didn't get what you paid for. If I were in your situation, I would be peeved at the thought of having to redo work I'd already done, but I would rather go back and rework it and suffer a little aggravation now, than suffer the long-term aggravation of having a setup that's "not quite right".

(Not Clifford or CompCams or Summit or JEGs).

Author:	SpaceFrank [ Mon Jan 09, 2006 9:09 pm ]
Post subject:
A few days ago I set my valve lash to .009/.019 with the engine hot. The idle is considerably smoother now, but it's still not perfect. At higher RPMs, it sounds great. I dug out the paperwork on my cam, and found that it has 448 lift, 264 duration, and 109 lobe (don't know what that last one means). How do I determine proper valve lash settings, given the numbers from the camshaft? Can I do any better than what it is right now?

Author:	rock [ Tue Jan 10, 2006 6:53 am ]
Post subject:	ok slantsix dan and all, is this totally BS lash advice?
Nice thread y'all! I was reviewing invoices for parts for a rebuild I just finished. I saw I was shipped a RV cam for hydraulic lifters. Well I have solid lifters and my order was quite specific as to what cam I needed. I called the mfgr, and there grinder said "no problem, just set your lash at 8 and 12, not 10 and 20". I was thinking about pulling cover and re-setting lash this weekend if this advice is good. THe engine has not been fired yet so after reset would be its breakin run. Am I being BS'd to avoid a new cam free to me, or not? RIght now I am cold set at 10 and 20 because of new engine. rock 64d100

Author:	sandy in BC [ Tue Jan 10, 2006 7:22 am ]
Post subject:
if its brown and sticky..... No substitute for the right cam.....specially if you paid for it.

Author:	SlantSixDan [ Tue Jan 10, 2006 8:23 am ]
Post subject:	Re: ok slantsix dan and all, is this totally BS lash advice
Quote: I was shipped a RV cam for hydraulic lifters. Well I have solid lifters and my order was quite specific as to what cam I needed. I called the mfgr, and there grinder said "no problem, just set your lash at 8 and 12, not 10 and 20". BZZZT! No. Quote: Am I being BS'd to avoid a new cam free to me Yep! It's worth noting, since we're talking about deviating from factory lash specs, that the truck enginesâ€”with the same camshaft as the car engines, year by yearâ€”had a larger lash specified. 0.012" intake, 0.022" exhaust.

Author:	Charrlie_S [ Tue Jan 10, 2006 9:16 am ]
Post subject:
Rock, do you mind telling me who gave you that advise? Then I will know who to avoid.

Slant Six Forum https://slantsix.org/forum/

Fun with Valve Lash https://slantsix.org/forum/viewtopic.php?t=15566	Page 3 of 4

Author:	Doctor Dodge [ Tue Jan 10, 2006 8:29 pm ]
Post subject:	Re: ok slantsix dan and all, is this totally BS lash advice
Quote: Nice thread y'all! I was reviewing invoices for parts for a rebuild I just finished. I saw I was shipped a RV cam for hydraulic lifters. Well I have solid lifters and my order was quite specific as to what cam I needed. I called the mfgr, and there grinder said "no problem, just set your lash at 8 and 12, not 10 and 20"... rock 64d100 I have to say that I have run solid lifters on a hydraulic cam and guess what.... they run fine but take less lash to keep them from "ticking". The "lash ramp' is very different between the two cam types, a solid cam uses a slow and long lash ramp, designed to allow some adjustment "range" and variation. A hydraulic ramp is short and fast, designed to quickly compress the oil pocket in the lifter. You can get the "mis-matched" set-up to work but you will have to adjust your way into a tight lash setting, a setting that will not be as forgiving to varation. I would also think that this type of combo would wear-out faster, especially with stiff valve springs. DD

Author:	SpaceFrank [ Tue Jan 10, 2006 9:32 pm ]
Post subject:
How does one go about determining the proper valve lash for a given camshaft?

Author:	Ice Titan [ Tue Jan 10, 2006 10:24 pm ]
Post subject:
Quote: LOBE SEPARATION ANGLE: This is the relationship between the centerlines of the intake and exhaust lobes. A 110-degree lobe separation angle means that the peak opening points of the intake and exhaust lobes are 110 degrees apart. This is ground into the cam and canâ€™t be changed without changing cams. Lobe separation angle is another way of expressing overlap, which is the term formerly used by cam manufacturers. Overlap is the amount of time that both valves are open in the same cylinder. When both valves are open at the same time, cylinder pressure drops. A cam with 106 degrees of lobe separation angle will have more overlap and a rougher idle than one with 112 degrees, but itâ€™ll usually make more midrange power. Shouldn't your lash be on your card?

Author:	Doctor Dodge [ Tue Jan 10, 2006 10:29 pm ]
Post subject:
Quote: How does one go about determining the proper valve lash for a given camshaft? You should have the cam's profile measured and "graphed" by a cam grinder, to show the shape of the lash ramps. Another method is to use a dial indicator and a degree wheel to get a general idea on what the lash ramp looks like but you will still have to run the engine to see how it reacts to different adjustments. In the end, you use "trial & error" to find the lash setting(s) where the engine runs the best, without excessive tappet noise or a rough idle. DD

Author:	rock [ Wed Jan 11, 2006 6:45 am ]
Post subject:	Thanks to all who replied , and DD's hyperpack 170
Folks, I am humbled by the willingness of the really knowledgeable to assist all on the forum. Thanks so much for the collective wisdom on my hydro vs. solid cam question. I was pretty shocked and bummed out to contemplate tearing down a just-finished engine...a task I may not do now, thanks to DD. (His manifolds are on it!). I am still going to consider it though. I read in an old slant six news last nite DD's story about his hyperpack 170, but don't have the followup story on how the torrid 170 made out! rock '64d100

Author:	SlantSixDan [ Wed Jan 11, 2006 8:24 am ]
Post subject:	Re: Thanks to all who replied , and DD's hyperpack 170
Quote: I was pretty shocked and bummed out to contemplate tearing down a just-finished engine...a task I may not do now, thanks to DD. Think carefully...remember, DD also said this combination would probably wear faster. You paid for a specific cam; you didn't get what you paid for. If I were in your situation, I would be peeved at the thought of having to redo work I'd already done, but I would rather go back and rework it and suffer a little aggravation now, than suffer the long-term aggravation of having a setup that's "not quite right".

Author:	Charrlie_S [ Wed Jan 11, 2006 9:49 am ]
Post subject:	Re: Thanks to all who replied , and DD's hyperpack 170
Quote: [ Think carefully...remember, DD also said this combination would probably wear faster. You paid for a specific cam; you didn't get what you paid for. If I were in your situation, I would be peeved at the thought of having to redo work I'd already done, but I would rather go back and rework it and suffer a little aggravation now, than suffer the long-term aggravation of having a setup that's "not quite right". Those are exactly my thoughts. One other thing. Say the cam, wipes a lobe in less then a thousand miles. Do you think this cam company will honor the warrentee? I would bet they say "the installation was faulty, you used the wrong lifters". It's your money, why not get what you paid for?

Author:	NewLancerMan [ Wed Jan 11, 2006 10:27 am ]
Post subject:
We all feel your frustration rock! But do it right, and you'll always be happier. =) MJ

Author:	rock [ Fri Jan 13, 2006 2:14 pm ]
Post subject:	wrong cam story had happy ending
Guys, Thanks for advice and sympathy re. my discovery of the hydro cam instead of solid lifter cam. I absolutely agree with doing it all over since I always try to do it right, and darn it, the engine is out...it will never be easier to do again. SO using the information (lessons) I got in response, I again called the cam grinder. I mentioned that I regretted having to revisit the issue, but had been thinking that in light of a /6 resurgence (as in Mopar Muscle) plusthe existence of a large community of knowledgeable consumers I felth honor bound to inform, I wanted to see what could be done in a even up swap, at least. They "had been thinking about it" and I get to trade back for the right cam and get a cash "labor adjustment" . This would not have happened without your support...I was figuring to get screwed, but no, not this time. THe certainty of widespread permanent public naming of the firm was not desired by the firm, who after all is talking about less than $500. Now I can use the new knowledge from the group AND have my RV cam, too. (Not Clifford or CompCams or Summit or JEGs). Thought you would like to know of this board power. rock '64d100

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Author:	DusterIdiot [ Fri Jan 13, 2006 2:23 pm ]
Post subject:	Local guys?
Quote: (Not Clifford or CompCams or Summit or JEGs). Erson Lunati Isky Redline Elgin Engle Crane? Glad it got worked out! -D.Idiot