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Solid Roller Normal Noise?
https://www.youtube.com/watch?v=n_q2...ature=youtu.be
Does this sound normal for a solid roller? The car is new to me so I do not know all specs, have no cam card so lash is roughly all .020 on intake and exhaust. I have a sheet saying its a comp solid roller .575 lift 262* dur. @ .05, 106* INT. centerline, 110* lobe separation. |
Is that lash hot or cold? Sounds a little loose to me. If that is the cold setting they will be around .025/.026 when warm. I would set them around .015 cold and they will grow to around .020 warm and see what it sounds like.
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Lash sounds loose.
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Rent a chassis dyno for a few hours, and do a lash cycle.
Start by testing as-is. Make two pulls to make sure everything is consistent. Make all pulls with the coolant temp the same. Then start with the intake valves, tighten them all a thousandth or two. If power goes up, tighten some more. If power drops, go a thou or two bigger than you started with. Once you find the best last for the intake, do the same with the exhaust lash. Starting at 0.026" / 0.026" (per the cam card) and ending up at 0.021" / 0.024" was worth 15rwhp at peak and 25rwhp at about 1500rpm below peak on one of my old motors. |
Lash is cold. At this point I am not worried about squeezing every inch of horsepower. Just trying to make sure nothing seriously wrong is going on. I believe this motor was built at least 8 years ago but it pulls extremely hard. So if I tighten lash up to say .015 and noises persists should I tear it apart or just run it until it gets more prominent?
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A fwiw, going thru my older Comp catalog at solid roller lobes looking for 262 degrees duration and 0.575" lift. Their High Energy Street roller lobe 4221 calls for 0.020" lash with a 1.5 rocker ratio.
Valvetrain Tech: Lash Is Much More Than Just A Little Gap https://www.enginelabs.com/engine-te...-a-little-gap/ . . |
This from a tech article. Lash Changes....
WARNING. This might seem like a small thing, but it can be a subtle alarm. Mechanical lifter engines use lash or clearance between the rocker arm and the valve and despite a common misconception, if everything is working properly warm engine lash clearance do not change. If the lash changes – something is moving. This is true for both flat and roller lifter camshafts. Generally, if the lash increases, this means something is wearing which has increased the clearance in the valvetrain. This can be a flat tappet lifter that is in the process of flattening a cam lobe or it could mean a bent pushrod or perhaps a fractured rocker arm. With roller lifters, a minor increase of 0.003 to 0.005-inch of lash could be a warning sign that the lifter’s roller bearings are failing. This is just about the only signal you’ll get that something is wrong before the bearings begin to disintegrate. When that happens, their exit is quickly followed by catastrophic engine damage as those little needle bearings use engine oil to transport them throughout the engine. If you’ve never experienced this – consider yourself lucky. Those tiny little roller bearings end up between the pistons and cylinder walls – which can cause serious cylinder wall scoring. Or, they can find their way into the oil pump and cause it to seize, which is never a good thing. . |
It sounds like you have the comp 308R cam. The valves are set at .020 but you also have aluminum heads which from everything I’ve read is a different setting.
Hopefully someone else can shed more light on this. Butcher |
Yes, page 71 here:
http://www.compcams.com/Technical/Ca...terCatalog.pdf Another tid bit to consider, cell phones typically don't have fantastic built-in microphones. Often leading to degradation of audio quality. With a cell phone recording my solid roller set up sounds like a thrashing machine, not as bad in person. . |
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I see what you mean now mike
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Even if somebody's method of measuring the lash is not exact (one person's .020" may be another 0.024"), as long as you are consistent and the power is maximized, then you can be rather confident the lash is where it should be. |
I can't hear any noise coming from my solid roller with Eddy heads. I subtracted 0.006" from the recommended hot lash setting for the initial cold adjustment and I might have needed to make a slight adjustment on a couple rockers when it was readjusted hot.
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