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I am looking on info for lashing valves on a solid roller cam for my LS-7.I heard that solid lifter motors are lashed with the motor off.Also looking if there is a certain sequence to lashing the valves.

1970 SS396
 

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Get yourself a timing tape (Summit, JEGS) for the correct width of your harmonic damper. Clean the damper and put it on carefully. With the motor warm but not too hot to work on adjust your valves by the cam manufacturers specifications. Start on TDC of number one cylinder and adjust the valves; turning the engine by the dampers crankshaft bolt 90 degrees at a time in a clockwise fashion. Adjust by the engines firing order (i.e. 1,8,4,3,6,5,7,2) every 90 degrees of crankshaft rotation. Works for me!

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Bob (Creedmoor,N.C.)
65 Vette B&M Blown, Richmond 5-speed
68 Malibu B&M Blown, Turbo 350 10" converter
 

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Mr SS there is a sequence but your solid roller may have curves like Busty Hart, and it may not work. Some fellas simply watch for the adjacent valve to open and then adjust assuming the lifter is on the base circle. I use the 4 stop method. 4 valves adjusted at TDC, 90 ,BDC, 90. The only thing I have to tweak is the use of the starter to position and DZ just mentioned that with manual trans you can move the car in gear and get it much closer. That'll be a world of help.

So I don;t want to post the sequence , beacuse it may not work for you. I called Crane, my cam manufacturer, and for my mild LS6 type cam, the sequence in the factory shop manual works mint. Call your cam manufacturer.

Also, here's a tip I got fom a fellow member at TC, if you;re using rollers and polylocks ( which I strongly recommend ), you'll lose a few thou when you snug up the locking set screw. So I;ve gotten into the habit of getting close ( even a freckle tight ), locking and then finishing by retorquing the nut. It's only 1/2 thou but, hey, that's a big deal in these matters!

If you search on this site, you'll find the factory sequence, I posted it, but I'm at work so... but check with your cam manufacturer, big cams got wild curvaceous lobes and you can't use that method.

BTW, it took me ( lunkhead ) a few tries to get the "feel" of the adjustment right. 1 thou is not much.

[This message has been edited by Gene Chas (edited 02-21-2000).]
 

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Any automotive cam sets the same way, as defined by Comp Cams, hydraulic, solid, hydraulic roller or full solid roller.

Their method is as follows:

Do one cylinder's valve pair at a time,
Rotate the engine until the exhaust valve for the cylinder you are doing just starts to open, set that cyl's intake valve,

Continue to rotate the engine and the exhaust valve will open and close, the intake will open and just as it closes, set the exhaust valve for that cylinder.

Move on to the next cylinder's valve pair.

This method is the only method that gets every lobe on its base circle dead center, no matter the kind or grind of the cam.

Works on any type of cam, can be done for routine valve adjust maintenance or when the enigne is being built so the valve covers can be bolted up and not removed after the engine is put into dervice. Done right, there is no need to readjust them on hydraulic and hydraulic roller cam engines.
 

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SS,
Ignition man's procedure is dead on, the only way to be certain you are on the bottom of the lobe. If you want to save some turning though, the way I do it is to start with # 1, turn until the exhaust just starts to open, then adjust #1 intake. Then, instead of turning round and round until #1 intake opens and closes, I just turn the motor 1/4 turn...this puts you in the proper position to do the next intake valve in the firing order which would be #8...another 1/4 turn and you do #4 etc through the entire firing order. Then start all over with the #1 exhaust valve and go through the firing order again...doing all the exhaust. This way you only do a total of 4 complete revolutions of the motor. Much less wear and tear on the arm. As far as getting the feel of the adjustment goes, they do make special feeler gauge sets that are stepped. If for instance, you need to adjust the valve to .026" you use the gauge that is .025 on the end and steps up to .027 then you just tighten the valve until you can just get the feeler gauge in but not past the step. These are called go no-go gauges and are designed for doing valve adjustment. Most good auto parts stores should have them.
Hopr this helps,

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Bill Koustenis
Advanced Automotive Machine
Waldorf Md

1971 Heavy Chevy - original owner
Team Chevelle #100
 

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Do yourself a favor...since you'll be doing this often, run a remote (marine quality) starter button under the hood...just connect one wire to the start pos on your starter solenoid, and one to the battery + terminal...then mount your starter button somewhere handy on the inner fender or cowl...Makes the operation a one-person and much quicker affair.

Also set the lash to what your cam manufacture specifies, and check to make sure whether the lash setting they supply should be set with the engine warm (150-180 degrees) or cold (room temp)

-Good Luck!!

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68 El Camino...Slow, Much Work Required
98 Z28...Fast, No Work Required
Goodfellow AFB, San Angelo, TX -- Where? That's what I said..
 

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Ignitionman, I;m using your method the next time! Thnx.

Mr. SS the last detail I would add is that often the manufacturers spec betweeen hot/cold may not be what you experience. In my case I have a .004 thou dif between hot/cold, while crane indicated it would be 6 thou. Why? Don;t know. But that's what I measured. Start with recommended and check it for yourself one day.

Also, I've found that running my particular cam 2 thou looser gives me a nicer street powerband moving it from 3000-6500 to 2800-6300. It also bumps my idle vacuum up a freckle as one would expect by shortening duration a bit.
 

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PS, I always use the starter motor when the engine's in the car, and I always use my in-car remote starter button (I'm crazy, not dumb).

Just dis-able the ignition system when you do the setting in the car, please. Safety factor.
 

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A couple more things...
The lash will tighten up as it warms up, so if you've only got the warm specs, adding 3-4 thou might get you close enough to warm up the engine and recheck.
Also, pulling the sparkplugs sure makes a motor easier to turn by hand (I'm to spastic to hit the mark with the starter, remote switch or not)
Bryan

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'65 Malibu frame-off project(slow going!)
'70 C-20 Longhorn p/u (daily driver)
 

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Remember "EO-IC". Ignition man is correct but if you remember eo-ic you can never get the adjustment wrong. It means "When the EXHAUST begins to OPEN, set the intake. When the INTAKE begins to CLOSE, set the exhaust." I work each cyl. starting w/ # 1 and going down the row and then start on the other side on # 2 and go down that row.
I am new to the racing stuff and I understand this can be confusing. For instance, I know a guy who has a high 8 sec. Camaro who doesn't even know how to set his valves. Course that may explain why he's always having problems with it...
 

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Bryan,

Lash will tighten cold vs. hot on an iron head and block combo. Lash will loosen cold vs. hot on a iron block/aluminum head combo.

Jason Gore
AKA DragRacer
[email protected]
 

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Ok, this may sound stupid but i have always been told to set solid cams the way the old chevy manuals say to. Go to TDC #1 and set half the valves and then TDC #6 and set the rest. Is this wrong.....am I not getting all the power i can out of my engine? Please let me know if this is wrong....

Chris
 

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Hey Gene,I'll be using " a freckle" of this or that when I explain recipes to friends...a "freckle tight" is pretty cool.Ya need to market a gear-head y2k dictionary bud ! Shawn
 

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Blurat, the term we used to use is not politically correct, heck it never was.


BTW, I just picked up a remote starter switch from Sears for $10 on sale. Just in time for redo the valves in "Ignitionman" style. ( and check compression for I fear rings are KO'd).

Good luck with those solid cams fellow gearheads!

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Chaas
Gold #62/ACES
67 SS396/L88
 

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QAK, if you have a long-duration performance cam you'll likely end up with a few loose valves using the factory manual method. IgnitionMan and Bill K have the real deal, it's foolproof unless you're really asleep at the wheel, use it and be happy.

Tom
 

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I like the firing order method, which is where you adjust the valve on tdc compression and then rotate the motor 90 degrees and do the next cylinder in the firing order. The one place that I want the valve closed is on tdc compression. This also happens to be the way you do a leakdown test on a motor. I don't like the exhaust opening intake closing method because it takes too long and I always end up doing it wrong.
 
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