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You know, like looking around for the remote control so you can swill beer uninterrupted while clicking away later. Like only taking apart what HAS TO be taken apart when performing maintenance - NOT taking the carb off the manifold for a head swap, for instance. In the same vein, fellow gearheads, I pose these questions: I read somewhere (decades ago) that on a 90 degree V8 one can adjust all the valves with the crankshaft in just two positions. In one (crank position) you can do 8 valves, turn the crank 360 degrees and do the other 8. So, 1) Does this sound right? 2) Where to position the crankshaft? 3) Which valves at which crank position? I suppose I could reason it out if I had an old cam laying around. Seems like it would save time - not having to move the crank 16 times.
 

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Make sure that you only do that peocedure on a stock cam. It won't work with a hyperf. cam.
 

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Matt, you hit the nail on the head.
And It wont work if the cam is not installed straight up either, been there. Learnt it wont work with a aftermarket cam.
 

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From an LT1? no.
 

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Cat has been doing this forever.
But Cat tolerances and QC are miles ahead of automotive,Cats ain't hotrods, and like the other guys are telling you... it don't work on anything but a stock cam. On a V-16 Cat I use 2 crank positions. On my SBC's I use 8 crank positions. On a V-12 Waukesha I hope like hell I have a helper.
If you have a high performance engine, you want your valve lash set at the point in the rotation of the cam when cylinder pressures and temps are greatest. This is TDC compression. Setting the valves at any other position assumes your cam has a perfect base circle. Most don't.

You don't have to roll the engine 16 times, just 8.

Land it within a few degrees of TDC compression for each cylinder and adjust both valves.

Watch for overlap on the valves of the companion cylinder, then set valves on the firing cylinder. The companion cylinder is easily found by writing the firing order like this
1 8 4 3
6 5 7 2 (if you have conventional firing order)
on a disposable reference chart like a hunk of cardboard
The companion cylinder is either above or below, depends on where you are in the firing order.
As you rotate the engine in the direction of normal rotation watch the exhaust valve on the companion(6 for example). When it closes and the intake makes about 2 or 3 little dips, you are on TDC compression of the cylinder you set (1). Then watch 5 to set 8 etc . Each one will be exactly 90* apart, if your car allows put your ratchet vertical and turn it to horizontal, you'll be amazed how close that gets you.
Later
Tim
77 Camaro, Wolf by name
412SBC no juice or brake yet
10.85/126mph
 
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